Dissertations / Theses: 'Infective endocarditis'

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Mansur, Alfredo Jose. "Avaliação da probabilidade de óbito em portadores de endocardite infecciosa." Universidade de São Paulo, 1987. http://www.teses.usp.br/teses/disponiveis/5/5131/tde-21072014-100754/.

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Foram estudados 300 episódios de endocardite infecciosa (EI) em 288 pacientes acompanhados no Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, no período de outubro de 1978 a agosto de 1986, com o intuito de avaliar a probabilidade de óbito e assim identificar os pacientes sob maior risco de evolução desfavorável. As idades dos pacientes variaram entre 0,2 a 78 (média de 30, desvio padrão de 16,06) anos, correspondentes a pacientes do sexo masculino em 185 (62%) episódios e feminino em 115 (38%). Procedeu-se a análise univariada (testes de qui quadrado e exato de Fischer, análise de variância) para se identificar variáveis cujas distribuições diferissem quanto a mortalidade, para em seguida realizar a análise multivariada com o emprego de regressão logística, a fim de estimar a probabilidade de óbito. Para isso, foi desenvolvido um modelo estatístico e aplicado a casuística e, a casos hipotéticos, para o estudo conceitual. Não houve diferença de distribuição significativa quanto a mortalidade em relação a idade, sexo, tempo decorrido entre o início dos sintomas e a hospitalização, presença de antecedente de manipulação possível de induzir a bacteriemia, informação de lesão cutânea na história clínica, uso prévio de antimicrobiano, presença de petéquias, esplenomegalia, dimensão da área cardíaca na radiografia de tórax, presença de vegetação no ecocardiograma, duração da antibioticoterapia pre-operatória, portadores de aneurisma micótico, embolia arterial sistêmica, infecção em câmaras cardíacas direitas em relação à infecção de câmaras cardíacas esquerdas, infecção em prótese valvar antes ou depois de quatro meses de seu implante, infecção em prótese aórtica em relação à infecção de prótese mitral, prótese única em relação à dupla prótese, velocidade de eritrossedimentação, taxa de hemoglobina no sangue, taxas de gamaglobulina e creatinina séricas. Houve diferença significativa quanto à mortalidade considerando-se o estado cardíaco anterior à EI, a localização da EI, os agentes etiológicos, a alteração no exame do fundo de olho, o número de complicações, a taxa de mucoproteína e albumina séricas e a taxa de leucócitos do sangue, os portadores de infecção em prótese valvar em relação à infecção em estrutura natural. Na análise multivariada foram empregados o estado cardíaco anterior à EI (portadores de valvopatia, de prótese valvar cardíaca, de cardiopatias congênitas, e pacientes sem evidência de cardiopatia prévia), o agente etiológico [estreptococos, Staphylococcus aureus, outras bactérias (incluindo-se as bactérias gram-negativas, gram-positivas excetuando-se os estreptococos e os estafilococos, e os Staphylococcus epidermis) e os portadores de EI com hemoculturas negativas], a presença ou ausência de complicações e as taxas de leucócitos do sangue, de mucoproteína e de albumina séricas. O modelo estatístico desenvolvido, que incorporou informações do estado cardíaco anterior à EI, do agente etiológico, das complicações e da taxa de leucócitos do sangue, era aplicável a 229 episódios e permitiu prever adequadamente 158 entre 173 evoluções de pacientes que receberam alta hospitalar e 27 entre 56 evoluções de enfermos que faleceram; estimar como alta hospitalar 29 pacientes que faleceram e como óbito 15 pacientes que receberam alta hospitalar, classificando corretamente 185 dos 229 episódios. Aplicado a pacientes hipotéticos dos diferentes subgrupos considerados na análise o modelo demonstra, com base em nossa experiência, que a probabilidade de óbito será maior nos portadores de prótese valvar cardíaca, endocardite por microorganismos agrupados como \"outras bactérias\" (bactérias gram-negativas, Staphylococcus epidermidis, e outras bactérias gram positivas excetuando-se estafilococos e estreptococos) e por Staphylococcus aureus, na presença de complicações. À presença de complicações foi a variável que exerceu maior influência na probabilidade de óbito; a sua ausência minimiza sobremaneira essa probabilidade qualquer que seja o estado cardíaco anterior à EI e o agente etiológico. Nossos dados permitem sugerir que considerando de modo simultâneo e conjunto o estado cardíaco anterior à EI, o agente etiológico, a presença ou ausência de complicações e a taxa de leucócitos do sangue contribuem na avaliação prognóstica em portadores de EI. Entre essas variáveis, a participação da presença de complicações e a mais ressaltada. Na ausência de complicações a probabilidade de óbito reduz-se acentuadamente.
In order to assess the probability of death in the course of infective endocarditis we studied 300 episodes involving 288 patients, followed from October 1978 up to August 1986. The ages ranged from 0.2 to 78 (mean 30, standard deviation 16.06) years; 185 (62%) episodes occurred in male patients and 115 (38%) in female patients. As a first step we tested several variables against mortality through univariated analysis (chi square test, Fisher\'s exact test, analysis of variance). The variables showing significant differences in the univariated test were then submitted to multivariate analysis (logistic regression), to develop a statistical model to assess the contribution of each of the selected variable to the probability expression and to identify the probability of death for each patient. There was no significant difference in mortality related to age, sex, time elapsed between onset of symptoms and hospital admission, previous manipulation usually associated with bacteremia, information of cutaneous lesions, previous antimicrobial therapy, petechiae, splenomegaly, cardiac dimensions on chest roentgenogram, vegetations detected on echocardiogram, pre operative antibiotic therapy, presence of my cotic aneurysm, arterial embolism, right sided vs. left sided endocarditis, erythrocyte sedimentation rate, blood hemoglobin, serum gama globulin, serum creatinin, early prosthetic valve infection vs. late prosthetic valve infection, prosthetic aortic valve vs. prosthetic mitral valve, single prosthesis vs. two prosthesis. There was significant difference in mortality related to cardiac status before the endocarditis, etiologic agent, fundoscopic abnormality on indirect ophtalmoscopy, frequency of complications. serum mucoprotein, serum albumin, blood leukocyte count, prosthetic valve endocarditis in relation to native valve endocarditis. The model developed through logistic regression included the cardiac status before the endocarditis (valvular heart disease, congenital heart disease, prosthetic heart valves or no known heart disease}, etiologic agent (streptococci, Staphylococcus aureus, other bacteria, negative blood cultures), presence of complications, blood leukocyte count. The model could be applied to 229 episodes. It detected correctly the evolution in 185 of 229 episodes, and identified 158 in 173 patients discharged from the hospital as well as 27 in 56 patients who died. There was also prevision for hospital discharge in 29 patients who died and for death in 15 patients discharged from the hospital. The probability of death is higher in patients with prosthetic heart valve, when the etiologic agent is the Staphylococcus aureus and the group of gram negative bacteria, gram positive bacteria other than streptococci and staphylococci and Staphylococcus epidermis, in the presence of complications. In conclusion, the informations provided by cardiac status before the endocarditis, etiologic agent, presence or absence of complications and blood leukocyte count may be useful in the assessment of the outcome of patients with infective endocarditis.

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Watkin, Richard. "The diagnosis of infective endocarditis." Thesis, University of Birmingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408833.

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Carey, Andrew J., Devin Johnson, George Obeng, Zia Rahman, Abdul Hannan, and Jack Goldstein. "A Classic Presentation of Infective Endocarditis." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/asrf/2018/schedule/140.

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Introduction: Advances in modern medicine have enabled early detection of infective diagnosis through blood cultures and echocardiography, which have been standardized by the widely accepted Modified Duke Criteria and have enabled rapid administration of antibiotics. As a consequence, the well-discussed and often variable clinical findings have become less common and have relegated to minor criteria in diagnosis. Fever is the single most common presenting symptom, whereas more specific signs such as petechiae may be seen in only 20-40% of patients. Even more rare are the pathognomonic Janeway lesions, Roth spots, and Osler nodes. Here we present a case in which early diagnosis was established through minor criteria manifest upon physical exam, and we highlight the timely insight provided from physical exam. Case: A 29-year-old man was admitted to the hospital for altered mental status, fever, vomiting, diarrhea, and vertigo. His past medical history included IV drug abuse, thrombotic thrombocytopenia, Hepatitis C, and seizures. Upon admission, his encephalopathy progressed rapidly, and he was mechanically ventilated and started on hemodialysis. Blood cultures grew Methicillin sensitive Staphylococcus aureus and Elizabethkingia meningosepticum and susceptibilities were attained. Echocardiography showed 3.1 cm vegetation on the aortic valve. By the Modified Duke Criteria, the diagnosis of infective endocarditis was confirmed. Discussion: The increasing incidence of complex infective endocarditis—including polymicrobial infection as well as the increasing resistance to antibiotic therapy—poses challenges to the rapid assessment and treatment necessary to mitigate the multi-organ involvement and the devastating consequences of septic emboli. Developments in medical technology have expedited both the diagnosis and treatment of infective endocarditis, which has subsequently decreased the extent and frequency of classical signs. Nonetheless, this case illustrates the unavoidable vitality of the physical exam, because this patient’s quick and clear presentation enabled diagnosis solely through physical exam. Empiric antibiotic treatment was started promptly and subsequently adjusted based on culture and susceptibilities.

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Daga, Shruti. "Host-pathogen interactions influencing susceptibility to infective endocarditis." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/27859.

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Introduction: Bacterial-platelet-fibrin complexes (vegetations), form on cardiac valves in infective endocarditis and are associated with increased morbidity and mortality. Although the mechanisms of bacterium-platelet adhesion, platelet activation and aggregation that are likely to contribute to vegetation formation have been identified, experimental conditions employed in these studies do not accurately reflect bacterial growth in the human vasculature. In addition, the contribution of host genetic factors such as platelet receptor polymorphisms to the pathogenesis of infective endocarditis is unknown. Considering that Staphylococcus aureus is now the most common cause of infective endocarditis associated with a poor prognosis, the contribution of bacterial and host factors to bacterium-platelet interactions, platelet activation and severity of infective endocarditis were analysed. Methods and results: Influence of bacterial growth environment on S. aureus-platelet interactions: Platelet aggregometry was performed with a range of S. aureus clinical and genetically modified isolates grown in nutrient broth and whole human blood. Some strains grown in nutrient broth failed to induce platelet aggregation, whereas all S. aureus isolates induced platelet aggregation after growth in blood. S. aureus surface proteins clumping factors A and B, serine-aspartate repeats C, D and E, iron-regulated surface determinants A and B and staphylococcal protein A were not essential for platelet aggregation induced by S. aureus grown in human blood, but the lag time to aggregation was increased in a strain containing mutations in genes encoding fibronectin-binding proteins A and B. Correlation between platelet activation and susceptibility to infective endocarditis: Platelet activation was determined in patients with infective endocarditis using flow cytometry. Platelet P-selectin expression was reduced in patients with infective endocarditis as compared to healthy volunteers, but was higher in patients requiring surgery. Influence of host genetic polymorphisms on S. aureus-platelet interactions and outcome in infective endocarditis: Flow cytometry and platelet aggregometry were performed to determine the role of specific platelet receptor GPIIIa piAI/A2, GPIb Kozak sequence, human platelet antigen (HPA)-2, variable number of tandem repeats (VNTR) and FcγRIIa H131R polymorphisms in S. aureus-platelet interactions. The GPIIIa P1A1/A1 genotype, FcγRIIa H allele and GPIb Kozak sequence polymorphism were associated with increased S. aureus-induced platelet aggregation. GPIb VNTR alleles influenced aggregate formation in vitro and development of vegetations in patients with infective endocarditis. The GPIb HPA-2a/2a genotype was associated with increased incidence of the composite clinical end-point of embolism, heart failure, need for surgery and mortality in patients with infective endocarditis. Conclusions: These studies have indicated that host and bacterial factors influence infective endocarditis and S. aureus-platelet interactions under conditions reflective of the host environment. Bacterial factors expressed during growth in human blood, host platelet activation levels and platelet receptor polymorphisms may represent novel prognostic markers and therapeutic targets in infective endocarditis.

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Mohee, Amar Raj. "Infections in urological practice : bacteraemia and infective endocarditis." Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/6839/.

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Introduction. It is known that infections may occur after urological instrumentation, as some patients develop infective symptoms. The purpose of this study was to investigate bacteraemia in patients undergoing transurethral resection of the prostate (TURP) and catheter manipulation, using contemporary culture methods. Another aim was to explore the potential for molecular methods to detect, identify and quantify bacteraemia. We aim to evaluate the association between urological instrumentation and the development of infective endocarditis (IE). Methods. Microbiological molecular methods to identify and quantify bacteria in blood were developed. Blood samples were collected at different time points during the procedure from patients undergoing TURP and catheter manipulation to evaluate the presence of bacteria using both the culture and molecular methods. The association between risk factors (patient and procedural) and bacteraemia was analysed statistically. A case-control model was used to assess the association between the development of IE and a number of risk factors, including urological instrumentation. Results. Bacteraemia occurred in both sets of patients though most patients were asymptomatic. In the TURP group, bacteraemia occurred within the first twenty minutes of the procedure in spite of antibiotics prophylaxis. In the catheter manipulation group, bacteraemia was present even prior to any urological manipulation. The case-control model demonstrated an association between urological instrumentation and the development of IE. Conclusion. This study has shown that bacteraemia during urological instrumentation is more prevalent than previously thought but is largely asymptomatic. Moreover, antibiotic prophylaxis in TURP patients fails to stop a significant proportion of intra-procedure bacteraemias. Asymptomatic bacteraemia may explain the statistical association between urological instrumentation and IE has been demonstrated.

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Ekdahl, Christer. "Infective Endocarditis : aspects of pathophysiology, epidemiology, management and prognosis." Doctoral thesis, Linköping : Department of Clinical and Experimental Medicine, Linköping University, 2008. http://www.bibl.liu.se/liupubl/disp/disp2008/med1017s.pdf.

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Vesey, Peter Mark. "Antigen expression of oral streptococci associated with infective endocarditis." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324795.

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de, Villiers Marthinus Coenraad. "The changing landscape of infective endocarditis in South Africa." Master's thesis, Faculty of Health Sciences, 2019. http://hdl.handle.net/11427/31498.

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Background. Little is known about the current clinical profile and outcomes of patients with infective endocarditis (IE) in South Africa. Methods. We conducted a retrospective review of the records of patients admitted to Groote Schuur Hospital between 2009 and 2016 fulfilling universal criteria for definite or possible IE, in search of demographic, clinical, microbiological, echocardiographic, treatment and outcome information. Results. 105 patients fulfilled the modified Duke criteria for IE. The median age of the cohort was 39 years (IQR 29-51), with a male preponderance (61.9%). The majority of patients (72.4%) had left-sided native valve endocarditis, 14% had right-sided disease, and 13.3% had prosthetic valve endocarditis. A third of the cohort had rheumatic heart disease. Although 41.1% of patients with left-sided disease had negative blood cultures, the three most common organisms cultured in this subgroup were Staphylococcus aureus (18.9%), Streptococcus spp. (16.7%) and Enterococcus spp. (6.7%). Participants with right-sided endocarditis were younger (29 years (IQR 27-37)), were predominantly intravenous drug users (IVDU; 73.3%) and the majority cultured positive for S. aureus (73.3%) with frequent septic pulmonary complications (40.0%). The overall in-hospital mortality was 16.2%, with no deaths in the group with right-sided endocarditis. Predictors of death in our patients were heart failure (OR 8.16, CI 1.77-37.70; p=0.007) and an age > 45 years (OR 4.73, CI 1.11- 20.14; p=0.036). Valve surgery was associated with a reduction in mortality (OR 0.09, CI 0.02-0.43; p=0.003). Conclusions. Infective endocarditis in a typical teaching tertiary care centre in South Africa remains an important clinical problem. In this setting, it continues to affect mainly young people with post-inflammatory valve disease and congenital heart disease. IE is associated with an in-hospital mortality that remains high. Intravenous drug-associated endocarditis caused by S. aureus is an important IE subset, comprising approximately 10% of all cases, a fact which was not reported 15 years ago, and culture-negative endocarditis remains highly prevalent. Heart failure in IE carries significant risk of death and needs a more intensive level of care in hospital. Finally, cardiac surgery was associated with reduced mortality, with the largest impact in those patients with heart failure.

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Wong, Chloe. "Patients Diagnosed with Infective Endocarditis: A Retrospective Chart Review." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1591717038456204.

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Turner, Lauren. "Identification of Virulence Determinants for Streptococcus sanguinis Infective Endocarditis." VCU Scholars Compass, 2008. http://scholarscompass.vcu.edu/etd/1560.

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Streptococcus sanguinis is the second most common causative agent of bacterial infective endocarditis (IE). Risk of S. sanguinis IE is dependent on pre-disposing damage to the heart valve endothelium, which results in deposition of clotting factors for formation of a sterile thrombus (referred to as vegetation). Despite medical advances, high mortality and morbidity rates persist. Molecular characterization of S. sanguinis virulence determinants may enable development of prevention methods. In a previous screen for S. sanguinis virulence determinants by signature-tagged mutagenesis (STM) an attenuated mutant was identified with a transposon insertion in the nrdD gene, encoding an anaerobic ribonucleotide reductase. Evaluation of this mutant, as well as an nrdD in-frame deletion mutant, JFP27, by a soft-agar growth assay confirmed the anaerobic growth sensitivity of these strains. These studies suggest that an oxygen gradient occurs at the site of infection which selects for expression of anaerobic-specific genes at the nexus of the vegetation. The random STM screen failed to identify any favorable streptococcal surface-exposed prophylactic candidates. It was also apparent that additional genetic tools were required to facilitate the in vivo analyses of mutant strains. As it was desirable to insert antibiotic resistance markers into the chromosome, we identified a chromosomal site for ectopic expression of foreign genes. In vitro and in vivo analyses verified that insertion into this site did not affect important cellular phenotypes. The genetic tools developed facilitated further in vivo screening of S. sanguinis cell wall-associated (Cwa) protein mutants. A directed application of STM was employed for a comprehensive analysis of this surface protein class in the rabbit model of IE. Putative sortases, upon which Cwa proteins are dependent for cell surface localization, were also evaluated. No single S. sanguinis Cwa protein was determined essential for IE by STM screening; however competitiveness for colonization of the infection site was reduced for the mutant lacking expression of sortase A. The studies described here present a progressive picture of S. sanguinis IE, beginning with surface protein-dependent colonization of the vegetation in early IE, that later shifts to a bacterial persistence in situ dependent on condition-specific housekeeping genes, including nrdD.

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Turner, Lauren Senty. "Identification of virulence determinants for streptococcus sanguinis infective endocarditis /." Online version not available until 8/4/2013, 2008. http://hdl.handle.net/10156/2243.

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Aitchison, Eileen J. "The antigenic composition of Streptococcus faecalis associated with infective endocarditis." Thesis, Aston University, 1987. http://publications.aston.ac.uk/12558/.

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Shorrock, Patricia J. "Surface properties of enterococcus faecalis in relation to infective endocarditis." Thesis, Aston University, 1990. http://publications.aston.ac.uk/12534/.

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The effect of growth conditions on both the appearance and the antigenic profile of cells of Enterococcus faecalis was investigated using electron micrographs of ruthenium red stained and sectioned cells and SDS-PAGE and blotting techniques respectively. Three specific antigens of molecular weights 73, 40 and 37 kdaltons were of particular interest being expressed most strongly after growth in serum. This medium was deemed to most closely mimic jn vjvo growth conditions reflecting an environment similar to that which the microorganisms would encounter during bacteraemia, preceding the colonisation of the endocardium and the development of infective endocarditis. The 40 and 37 kdalton antigens were shown by immunoqold labelling to be exposed on the surface of the cells although they did not appear to be connected with the fimbriae shown to exist on some of the E. faecalis cells examined by negative staining. The 73, 40 and 37 kdalton antigens were crudely purified using sarkosyl and ammonium sulphate precipitation, and used as the basis of a serodiagnostic test for E. faecalis endocarditis using an ELISA system. This was tested in a blind trial and the success rates were 94% for positives, 90% for negatives with endocarditis caused by other organisms and 80% for E. faecalis infections other than endocarditis. The binding of E.faecalis cells to the serum proteins fibronectin and albumin was investigated using 125I labelled proteins, followed by Scatchard analysis. This showed that· E.faecalis cells do loosely bind large amounts of both of these proteins, thus surely affecting the way in which the host's immune system perceives the cells. The E.faecalis receptor for fibronectin was partially characterised and appeared to involve protein and/or carbohydrate containing components. but did not involve LTA or the 40 and 37 kdalton species specific antigens.

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Albittar, Mohammed [Verfasser]. "Prophylaxis of infective endocarditis in oral and maxillofacial surgery / Mohammed Albittar." Ulm : Universität Ulm, 2021. http://d-nb.info/1233737503/34.

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Lowe, Adrian Mark. "Molecular characterisation of surface antigens of Enterococcus faecalis in infective endocarditis." Thesis, University of Bath, 1994. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387412.

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Flatman, Jennifer Catherine. "Characterisation of the Enterococcus faecalis EfaA gene product in infective endocarditis." Thesis, University of Bath, 1999. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285413.

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Sriramoju, Vindhya M. D., Sowminya M. D. Arikapudi, Sarah M. D. Arif, Muazzam M. D. Ali, Suhitha M. D. Madhavaram, Michael M. D. Zhang, Abdul M. D. Hannan, and Christopher T. M. D. Cook. "Elizabethkingia Meningoseptica Bacteremia associated with Infective Endocarditis in an Intravenous Drug Abuser." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/asrf/2018/schedule/201.

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Elizabethkingia Meningoseptica (E. Meningoseptica) an oxidase-positive gram-negative aerobic rod.1-2 Although ubiquitous in nature and widely distributed in soil and water, it is not a part of normal human flora. Cases of outbreaks of meningitis in premature neonates or infants have been reported, however, very few cases have been reported in adults.3 Infection is primarily nosocomial, or hospital acquired and has been implicated in bacteremia, meningitis, pneumonia, endocarditis especially in immunocompromised individuals.2-4 We report a 29-year-old male with past medical history significant for intravenous drug abuse, hepatitis C, oxymorphone induced hemolytic uremic syndrome, who presented to hospital with altered mental status. On admission, patient was unresponsive to vocal commands, febrile (102.3 F), tachycardic and tachypneic. He had pinpoint pupils and diffuse petechiae. In addition, he had erythematous flat macular lesions on his palms and dorsum of hands as well as injection marks in left cubital fossa. Cardiac examination was significant for a grade III systolic murmur at apical region and diastolic murmur at left second intercostal space. Laboratory studies revealed thrombocytopenia (43,000m/microL), lactic acidosis (4.9mmol/L), serum creatinine (Cr) of 6.6 mg/dL, glomerular filtration rate (GFR) of 10 ml/min. Transthoracic echocardiogram (TTE) revealed large mobile vegetation on aortic valve measuring 3.6 x 0.72 cm. Patient’s presentation was consistent with infective endocarditis with the vegetation seen on TTE and patient’s physical findings. Magnetic Resonance Imaging of the brain showed numerous small hemorrhagic infarcts, likely secondary to emboli from aortic valve vegetation. Patient required intubation for airway protection and started on hemodialysis. He was initially started on Meropenem and Vancomycin for infective endocarditis and later switched to Ciprofloxacin based on blood cultures and sensitivities which revealed methicillin sensitive staphylococcus aureus and multi-drug resistant E. Meningoseptica. Patient was transferred to long term care facility after acute care at the hospital. The increasing incidence of polymicrobial infective endocarditis and increasing resistance to antibiotic therapy pose challenges to the rapid assessment and treatment to mitigate the multi-organ involvement with septic emboli. Reports of pathogenicity associated with native valve endocarditis with this organism is scarce and exist primarily in a very few case reports and is resistant to many traditional antibiotics.5,6 E. Meningoseptica has shown antimicrobial susceptibility to the newer quinolones, rifampin, trimethoprim/sulfamethoxazole and ciprofloxacin with reasonable activity.7 Due to the unusual pattern of antibiotic resistance, early switching to appropriate antibiotics based on sensitivities is crucial for survival in patients with E. Meningoseptica. References 1..Kim KK, Kim MK, Lim JH, Park HY, Lee ST. Transfer of Chryseobacterium meningosepticum and Chryseobacterium miricola to Elizabethkingia gen. nov. as Elizabethkingia meningoseptica comb. nov. and Elizabethkingia miricola comb. nov. Int J Syst Evol Microbiol.2005 May;55(Pt 3):1287-93. 2:Shinha T, Ahuja R. Bacteremia due to Elizabethkingia meningoseptica. IDCases. 2015 Jan 17;2(1):13-5. doi: 10.1016/j.idcr.2015.01.002. eCollection 2015. 3..Jung SH, Lee B, Mirrakhimov AE, Hussain N. Septic shock caused by Elizabethkingia meningoseptica: a case report and review of literature. BMJ Case Rep. 2013 Apr 3;2013. pii: bcr2013009066. doi: 10.1136/bcr-2013-009066. 4.Ratnamani MS, Rao R. Elizabethkingia meningoseptica: Emerging nosocomial pathogen in bedside hemodialysis patients. Indian J Crit Care Med. 2013 Sep;17(5):304-7. 5.Bomb K, Arora A, Trehan N. Endocarditis due to Chryseobacterium meningosepticum. Indian J Med Microbiol. 2007 Apr;25(2):161-2. 6.Yang J, Xue W, Yu X. Elizabethkingia meningosepticum endocarditis: A rare case and special therapy. Anatol J Cardiol. 2015 May;15(5):427-8. 7. Hsu MS, Liao CH, Huang YT, Liu CY, Yang CJ, Kao KL, Hsueh PR. Clinical features, antimicrobial susceptibilities, and outcomes of Elizabethkingia meningoseptica (Chryseobacterium meningosepticum) bacteremia at a medical center in Taiwan,1999-2006. Eur J Clin Microbiol Infect Dis. 2011 Oct;30(10):1271-8.

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Peñafiel-Sam, Joshua, Samuel Alarcón-Guevara, Sergio Chang-Cabanillas, Wilkerson Perez-Medina, Fernando Mendo-Urbina, and Eloy Ordaya-Espinoza. "Infective endocarditis due to Bartonella bacilliformis associated with systemic vasculitis: a case report." Sociedade Brasileira de Medicina Tropical - SBMT, 2017. http://hdl.handle.net/10757/622419.

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Infective endocarditis due to Bartonella bacilliformis is rare. A 64-year-old woman, without previous heart disease, presented with 6 weeks of fever, myalgias, and arthralgias. A systolic murmur was heard on the tricuspid area upon examination, and an echocardiogram showed endocardial lesions in the right atrium. Bartonella bacilliformis was isolated in blood cultures, defining the diagnosis of infective endocarditis using Duke’s criteria. Subsequently, the patient developed clinical and laboratory features compatible with antineutrophil cytoplasmic antibody-associated vasculitis. This case presents an uncommon complication of B. bacilliformis infection associated with the development of systemic vasculitis.

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Rushani, Dinela. "Cumulative incidence and predictors of infective endocarditis in children with congenital heart disease." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114498.

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Background: Infective endocarditis (IE) is an infection of the innermost layer of the heart. The American Heart Association guidelines for IE prevention have gradually evolved over the last decades, with the 2007 recommendations reducing the groups of patients indicated for antibiotic prophylaxis before invasive dental procedures. The evidence base for the guidelines is limited. Specifically, the risk of IE in a population-based cohort of patients with congenital heart disease (CHD) has not been reported. We sought to determine the cumulative incidence and predictors of the development of IE in children with CHD.Methods: We identified all patients with CHD who were children (0-18 years) during all or part of the observation period from 1990-2005 using a cohort of patients with CHD in Quebec derived from the province's administrative databases. Predictors of childhood acquisition of IE were analyzed using a calendar time-matched nested case-control design. Cumulative incidence from birth to age 12 was described in the subset of children born during the observation period and was computed as the complement of the Kaplan-Meier estimator. Incident IE was defined as the first ICD-9 diagnosis in the hospital discharge records. Two alternative definitions of the outcome involved a manual review of discharge diagnoses and any hospital-based IE diagnoses.Results: 39,977 children (0-18 years) with CHD were followed for 336,661 patient-years and 118 cases of IE were observed. Of these, 63 cases occurred in 22,589 children followed from birth to age 12. Overall, the average risk of IE by age 12 was 3.7/1,000 children (95% confidence interval [CI] 2.9 – 4.9). It ranged from 2.1-11.3 cases/1,000 children based on the alternative outcome definitions. IE was strongly associated with cardiac surgery 6 months before the index date, adjusted rate ratio [RR] 10.74 (95% CI: 3.79 – 30.45). The RRs (95% CI) for CHD types compared to shunt lesions were as follows: cyanotic CHD lesions 5.51 (3.20 – 9.48); endocardial cushion defects 3.98 (1.89 – 8.36); left-sided lesions 2.48 (1.35 – 4.55); right-sided lesions 1.54 (0.64 – 3.71); other CHD 1.94 (1.02 – 3.65). Young age was a strong predictor: age < 3 years 2.94 (1.92 – 4.52); age 3-6 years 0.72 (0.38 – 1.37); with age 6-18 as the reference group. These findings were qualitatively insensitive to the definition of IE.Conclusions: We documented that the childhood risk of IE was highest in the earliest years of life, varied substantially by CHD lesion, and was strongly associated with cardiac surgery in the previous 6 months. These results help identify children who are at elevated risk of IE and should inform the development of future IE prevention guidelines.
Contexte: L'endocardite infectieuse (EI) est une infection de la couche la plus interne du cœur. Les lignes directrices de l'American Heart Association concernant la prévention de l'EI ont progressivement évolué au cours des dernières décennies. Selon les recommandations révisées en 2007, le nombre de groupes ciblés pour l'antibioprophylaxie avant des interventions dentaires invasives a considérablement diminué. Les données probantes sur ces lignes directrices sont limitées. Précisément, le risque de l'EI chez les patients atteints de cardiopathie congénitale (CPC) est inconnu. Nous avons cherché à déterminer l'incidence cumulative et les facteurs prédictifs liés au développement d'EI chez les enfants ayant une CPC. Méthodologie: En utilisant une cohorte des patients atteints de CPC qui provenait des données administratives du Québec, nous avons identifié tous les patients ayant CPC qui étaient des enfants (0-18 ans) pendant une partie ou toute la période entre 1990 et 2005. Une étude cas-témoins nichée dans la cohorte, dont les cas et les témoins étaient appariés sur le temps d'observation, a été menée afin d'analyser les facteurs prédictifs du développement de l'EI lors de l'enfance. L'incidence cumulative dès la naissance jusqu'à l'âge de 12 ans a été décrite chez le sous-ensemble des enfants nés au cours de la période d'observation et a été déterminée par le complément de l'estimateur de Kaplan-Meier. L'EI incidente a été définie comme le premier diagnostic CIM-9 (Classification internationale des maladies) dans le registre des congés hospitaliers. Deux autres définitions d'issue comportaient l'examen manuel des diagnostics d'EI au congé hospitalier, ainsi que tous diagnostics d'EI rendus en milieu hospitalier. Résultats: 39 977 enfants (0-18 ans) atteints de CPC sont suivis pendant 336 661 patients-années dont 118 cas de l'EI sont observés. Parmi ceux-ci, 63 cas sont survenus chez 22 589 enfants qui sont suivis dès la naissance jusqu'à l'âge de 12 ans. Le risque moyen de l'EI avant l'âge de 12 ans était 3,7 pour 1000 enfants (intervalle de confiance [IC] à 95%: 2,9 – 4,9). Selon les différentes définitions de l'EI, ce risque variait de 2,1 à 11,3 cas pour 1000 enfants. La chirurgie cardiaque 6 mois avant la date index était fortement associée à l'EI, le rapport de taux ajusté [RR] 10,74 (IC à 95%: 3,79 – 30,45). Les RR (IC à 95%) pour les types de CPC par rapport aux lésions des shunts étaient: CPC cyanogène 5,51 (3,20 – 9,48); communication auriculoventriculaire 3,98 (1,89 – 8,36); lésions du côté gauche 2,48 (1,35 – 4,55); lésions du côté droit 1,54 (0,64 –3,71); autre CPC 1,94 (1,02 – 3,65). Le jeune âge était un facteur prédictif fort: âge < 3 ans 2,94 (1,92 – 4,52); âge 3-6 ans 0,72 (0,38 – 1,37); par rapport à l'âge 6-18. Qualitativement ces résultats étaient insensibles aux définitions de l'EI. Conclusions: Nous avons démontré que le risque de l'EI chez les enfants étaient le plus élevé au cours des premières années de la vie, variait considérablement par le type de CPC, et était fortement associé à la chirurgie cardiaque dans les 6 mois précédents. Ces résultats aident à identifier des enfants à haut risque de l'EI et devraient contribuer à orienter les prochaines modifications aux lignes directrices sur la prévention de l'EI.

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20

Banks, Julia Barbara. "Isolation and characterisation of cytokine-modulating proteins from bacteria implicated in infective endocarditis." Thesis, University College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248218.

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21

周娉瑤 and Ping-yiu Chow. "Antibiotic prophylaxis for the prevention of infective endocarditis incongenital heart disease: knowledge ofparents and dentists." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43250907.

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22

Chow, Ping-yiu. "Antibiotic prophylaxis for the prevention of infective endocarditis in congenital heart disease knowledge of parents and dentists /." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43250907.

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23

Willoughby, Mark. "Infant and Childhood Infective Endocarditis in the Western Cape, South Africa: A Retrospective Review." Master's thesis, Faculty of Health Sciences, 2021. http://hdl.handle.net/11427/33093.

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Introduction Infective endocarditis is a microbial infection of the endothelial surface of the heart, predominantly the heart valves, that is associated with high mortality and morbidity. Few contemporary data exist regarding affected children in our context. Aims and Objectives: We aimed to describe the profile and treatment outcomes of infant and childhood endocarditis at our facilities. Methods: This is a retrospective review of infants and children with endocarditis at two public-sector hospitals in the Western Cape Province of South Africa over a 5-year period. Patients with “definite” and “possible” endocarditis according to Modified Duke Criteria were included in the review. Results: Forty-nine patients were identified for inclusion; 64% of patients met “definite” and 36% “possible” criteria. The in-hospital mortality rate was 20%; 53% of patients underwent surgery with a post-operative mortality rate of 7.7%. The median interval from diagnosis to surgery was 20 days (interquartile range 9-47 days). Valve replacement occurred in 28% and valve repair in 58%. There was a significant reduction in valvular dysfunction in patients undergoing surgery and only a marginal improvement in patients treated medically. Overall, 43% of patients had some degree of residual valvular dysfunction. Conclusion: Endocarditis is a serious disease with a high in-hospital mortality and presents challenges in making an accurate diagnosis. Despite a significant reduction in valvular dysfunction, a portion of patients had residual valvular dysfunction. Early surgery is associated with a lower mortality rate, but a higher rate of valve replacement when compared to delayed surgery.

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24

Herrera, Alfa. "Staphylococcus aureus TSST-1 and Beta-toxin contribute to infective endocarditis via multiple mechanisms." Diss., University of Iowa, 2016. https://ir.uiowa.edu/etd/5775.

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Staphylococcus aureus is a gram positive bacterium asymptomatically colonizing 30-40% of the human population. S. aureus causes a variety of infections including superficial skin lesions, toxic shock syndrome, and infective endocarditis (IE). There are 100,000 cases of IE each year in the United States. IE is a life threatening infection of native/prosthetic valves and the lining of the heart. It is characterized by the formation of vegetations, “cauliflower-like” structures composed of bacteria and host factors. S. aureus is the most commonly identified pathogen (up to 40%) in patients with IE. USA200 (Clonal Complex 30) strains of S. aureus are significantly associated with IE, all of which produce toxic shock syndrome toxin-1 (TSST-1) and β-toxin. TSST-1 characterizes the staphylococcal Group I superantigens (SAgs). The major mechanism of activity of TSST-1 and other SAgs is the ability to activate T-cells and APCs by non-specifically cross-bridging Vβ-chains of T-cell receptors (TCRs) with α and/or β-chains of major histocompatibility complex II (MHCII) molecules on antigen presenting cells (APCs). In a rabbit model of IE and sepsis, TSST-1 is critical for the development of vegetations and the associated colony forming units (CFUs). β-toxin has a molecular mass of 35 kDa, a basic pI (>10.0), and is a member of the DNase I superfamily. This cytotoxin has two distinct mechanisms of action: sphingomyelinase (SMase) activity and DNA biofilm ligase activity. β-toxin is critical for causing IE in a rabbit model that strongly resembles human disease. This toxin association had been observed, but studies have not been completed to determine what role TSST-1 and β-toxin play independently and in cooperation with one another, and more specifically which mechanism each uses, during IE infections. While TSST-1 and β-toxin are both important for IE, they are very different toxins. My studies determined that the presence of TSST-1 and β-toxin in combination results in the highest levels of lethality in a rabbit model of IE. A strain expressing TSST-1 lacking superantigenic activity has decreased lethality compared to the same strain expressing wild type TSST-1. My study is the first to begin characterization of the DNA biofilm ligase active site by identifying important residues via a DNA binding and biofilm formation assays. Furthermore, my research shows that a β-toxin mutant lacking SMase activity is decreased in lethality and vegetation formation compared to wild type. β-toxin mutants disrupted in biofilm ligase activity do not decrease lethality but are deficient in vegetation formation compared to wild type. Utilizing in vitro assays to assess cellular events during IE, I established that β-toxin causes changes to morphology and is cytotoxic to human aortic endothelial cells (HAECs), inhibits production of IL-8, and modulates the expression levels of cluster of differentiation 40 (CD40) and vascular cell adhesion molecule 1 (VCAM-1). My work shows these two virulence factors (TSST-1 and β-toxin) produced by USA200 strains and other clonal groups play important roles in causing IE.

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Murray, A. N. "Native valve infective endocarditis : a twenty two month prospective study at Groote Schuur Hospital with special reference to the diagnostic and prognostic implications of detection of vegetations by two-dimensional echocardiography." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/25828.

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26

Trinh, My. "Role of Two-Component System Response Regulators in Virulence of Streptococcus pneumoniae TIGR4 in Infective Endocarditis." VCU Scholars Compass, 2011. http://scholarscompass.vcu.edu/etd/2374.

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Streptococci resident in the oral cavity have been linked to infective endocarditis (IE). While viridans streptococci are commonly studied and associated with IE, less research has been focused on Streptococcus pneumoniae. Two-component systems (TCSs), consisting of a histidine kinase (HK) protein and response regulator (RR) protein, are bacterial signaling systems that may mediate S. pneumoniae TIGR4 strain virulence in IE. To test this hypothesis, TCS RR mutants of TIGR4 were examined in vivo through use of rabbit models. There were 14 RR proteins identified and 13 RR mutants synthesized because SP_1227 was found to be essential. The requirement of the 13 RRs for S. pneumoniae growth in IE models was assessed by quantifying mutants after overnight inoculation in IE infected rabbits through use of real time PCR (qPCR), colony enumeration on antibiotic selection plates, and competitive index assays. Real time PCR pinpointed several candidate virulence factors. Candidate RR SP_0798 was selected to be further examined. In the in vivo model, mutant SP_0798 grew significantly less than our control mutant SP_1678, which encodes a hypothetical protein and grew at a comparable rate to wild-type TIGR4 strains. Literature and databases identified SP_0798 as the ciaR gene, which has roles in regulating many diverse cellular functions. Our data suggests that RR SP_0798 is a virulence factor of S. pneumoniae TIGR4 strain in IE. This research may place more emphasis on virulence factors and lead to novel methods to combat pneumococcal endocarditis.

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Macarthur, Deborah Jane. "Mapping the proteome of Streptococcus gordonii." University of Sydney. Health Science, 2005. http://hdl.handle.net/2123/686.

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Streptococcus gordonii is a primary coloniser of the tooth surface where it efficiently ferments carbohydrates at pH levels above 6.0. By not being able to maintain the pH of dental plaque to a level required for enamel dissolution, the dominance of S. gordonii in dental plaque is considered a sign of a healthy oral cavity. However, upon entering the bloodstream and encountering a rise in pH, S. gordonii may become pathogenic, being one of the major causative organisms associated with infective endocarditis. Proteome analyses of S. gordonii grown at steady state in a chemostat allowed the phenotypic changes associated with alterations in pH levels characteristic of these two environments to be determined. As an initial starting point to this study, a two-dimensional electrophoresis (2- DE) reference map of S. gordonii grown at pH 7.0 was produced. Although only 50% of the S gordonii genome was available in an annotated form during the course of this study, the closely related Streptococcus pneumoniae genome (with which S. gordonii shares 97.24% DNA sequence homology) had been completed in 2001. The use of both of these databases allowed many of the S. gordonii proteins to be identified by mass spectrometry. Four hundred and seventy six protein spots, corresponding to 250 different proteins, or 12.5% of the S. gordonii proteome, were identified, giving rise to the first comprehensive proteome reference map of this oral bacterium. Of the 250 different proteins, 196 were of cellular origin while 68 were identified from the extracellular milieu. Only 14 proteins were common to both compartments. Of particular interest among the 54 uniquely identified extracellular proteins was a homologue of a peptidoglycan hydrolase that has been associated with virulence in S. pneumoniae. Among the other proteins identified were ones involved in transport and binding, energy metabolism, translation, transformation, stress response and virulence. Twelve cell envelope proteins were identified as well as 25 others that were predicted to have a membrane association based on the presence of at least one transmembrane domain. The study also confirmed the existence of 38 proteins previously designated as �hypothetical� or with no known function. Mass spectral data for over 1000 protein spots were accumulated and archived for future analysis when sequencing of the S. gordonii genome is finally completed. Following the mapping of the proteome of S. gordonii, alterations in protein spots associated with growth of the bacterium at pH intervals of 0.5 units in the pH range 5.5 - 7.5 were determined. Only 16 protein spots were shown to be significantly altered in their level of expression despite the range of pH studied. Among the differentially expressed proteins was a manganese-dependent inorganic pyrophosphatase (PpaC), which regulates expression of adhesins required for coaggregation. The expression of PpaC was highest at pH 6.5 - 7.0, the pH of a healthy oral cavity, indicating that PpaC may play an important part in dental plaque formation. Another differentially expressed protein was the heat-inducible transcription repressor (HrcA). Alterations in HrcA were consistent with its role as a negative repressor in regulating heat-shock proteins at low pH, even though no changes in the level of heat-shock proteins were observed as the pH declined. This result gave rise to the hypothesis that the possible reason cariogenic bacteria, such as Streptococcus mutans, can out compete S. gordonii at low pH might simply be due to their ability to manipulate their proteome in a complex manner for survival and persistence at low pH, unlike S. gordonii. This may imply some prevailing level of genetic regulation that is missing in S. gordonii.

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Maisterra, Santos Olga. "Complicaciones neurológicas de la endocarditis infecciosa al inicio del nuevo siglo: importancia del neurólogo en su atención integral." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/400151.

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Las complicaciones neurológicas de la endocarditis infecciosa (EI) constituyen un problema clínico mayor puesto que producen una elevada morbimortalidad. Sin embargo, aún no se conoce en profundidad cómo se pueden prevenir o detectar precozmente y cómo se han de tratar para mejorar el pronóstico de estos pacientes. En la presente tesis se planteó si la presencia activa de un neurólogo en el equipo multidisciplinar de la EI pudiera repercutir positivamente en la atención integral de los pacientes con EI y complicaciones neurológicas al favorecer la detección y diagnóstico precoz de las complicaciones neurológicas y optimizar su tratamiento y el momento para la cirugía cardiaca si se precisara. Los objetivos fueron analizar las complicaciones neurológicas en un centro de referencia de la EI en la actualidad: epidemiología, tipo de complicaciones, morbimortalidad e impacto en el pronóstico, prestando especial atención a las complicaciones cerebrovasculares, que son las más frecuentes y que más morbimortalidad generan. Así mismo, se compararon las características clínicas y el pronóstico en los pacientes con EI y complicaciones neurológicas antes y después de la incorporación reglada de Neurología en el equipo multidisciplinar y se evaluó el impacto de dicha colaboración en el diagnóstico y tratamiento de las complicaciones neurológicas y la influencia en la toma de decisiones de planificación de cirugía cardiaca cuando se precisó. Se analizaron las complicaciones neurológicas desde que existe el registro prospectivo del comité de Endocarditis Infecciosa del Hospital Universitari Vall d’Hebron, enero del año 2000, hasta el final de 2015 y se valoró la repercusión de la presencia de Neurología en el comité, que dio comienzo en el año 2013. Del total de 793 pacientes con EI, 161(20,3%) tuvieron complicaciones neurológicas y éstas se dieron más en los pacientes con EI sobre válvulas nativas izquierdas, con comorbilidad elevada y/o cuyo agente etiológico es S.aureus. Ocurrieron en los primeros días de la enfermedad o fueron el debut de la misma, casi la mitad de los pacientes precisaron cirugía cardiaca y originaron una elevada mortalidad. Las más frecuentes fueron las vasculares, sobre todo las isquémicas. A partir de 2013, los pacientes presentaron más comorbilidad y las complicaciones neurológicas ocurrieron más frecuentemente sobre válvulas protésicas biológicas. Desde la incorporación de Neurología al equipo multidisciplinar, hubo un mayor uso de resonancia magnética, una mayor detección de complicaciones no vasculares y un mayor número de pacientes con varias complicaciones neurológicas. Se implementó el uso de escalas neurológicas de gravedad y funcionalidad y de nuevos tratamientos en fase aguda del ictus. La mortalidad en el periodo 2013-2015 fue menor de forma estadísticamente significativa tras ajustar por los factores asociados a la misma, lo que apoya la relevancia de la presencia de Neurología en el equipo de EI. Como limitaciones más relevantes del estudio, destacaron que se trata de un análisis realizado en un centro de referencia para cirugía cardiaca y EI, con lo que los resultados pueden no ser extrapolables a la población general con EI, que existieron datos que no es posible contrastar con el periodo anterior a la entrada del neurólogo porque no se registraban previamente, y que el menor tamaño muestral desde la incorporación de Neurología, pudo conllevar una pérdida de la capacidad para detectar diferencias significativas en los subanálisis. En resumen, la integración de un especialista en Neurología en el equipo multidisciplinar de EI favoreció una mejor calidad de asistencia a los pacientes con EI y complicaciones neurológicas que revirtió en un mejor pronóstico.
Neurological complications in Infective Endocarditis (IE) are a major clinical problem as they cause high morbidity and mortality rates. However, it is still unknown how they can be prevented or early detected or how they should be managed to improve patients’ prognosis. In this thesis we wondered whether the active presence of a neurologist in the IE multidisciplinary team could result in better comprehensive care of patients with IE and neurological complications, as early detection and diagnosis of these neurological complications and their treatment, including appropriate time to cardiac surgery, if needed, is improved. The aim was to analyze neurological complications in a referral IE center at present, taking into account epidemiology, type of neurological complication, morbidity, mortality and prognosis impact, and paying especial attention to neurovascular complications, as they are the most frequent and have worse morbidity and mortality rates. Furthermore, clinical characteristics and prognosis of patients with IE and neurological complications before and after the active participation of the neurologist in the IE team were compared. Impact of this participation in diagnosis and treatment of neurological complications and influence in decision making for cardiac surgery when it was necessary were also evaluated. Data were collected from the prospective register of the Hospital Universitari Vall d’Hebron IE team that was begun in 2000, until December 2015. Impact of neurologist’s participation from January 2013 was evaluated. Of the 793 patients with IE, 161 (20.3%) had neurological complications. Native left side IE, high comorbidity and IE caused by S.aureus were risk factors for having these complications and they occurred in the first days of the disease or even were the first symptom. Nearly half of the patients underwent cardiac surgery and mortality among patients was high. The most frequent neurologic complications were strokes, most of them ischemic. From 2013 until 2015, patients had higher comorbidity and there were more patients with biological prosthetic valve IE. Since the neurologist’s involvement in the IE team, more Magnetic Resonance scans were performed, and more non vascular neurological complications detected. They were also more diagnoses of patients with several neurological complications. Neurologic stroke severity and functional scales and new treatments for acute stroke were introduced. Mortality in 2013-2105 period was significantly lower after adjusting for other mortality associated factors, what supports the relevance of the neurologist in the IE multidisciplinary team. The most important limitations of the study were that the series was from a referral center of cardiac surgery and IE, so results perhaps are not representative for IE general population; there were some variables that were not possible to contrast as they were not collected in the previous period without neurologist, and also, small sample size in the period whit neurologist could result in less power to detect differences in subanalysis. To summarize, neurologist’s participation in the IE multidisciplinary team helped to have better quality of comprehensive care for patients with IE and neurological complications that resulted in better prognosis.

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29

Macarthur, Deborah Jane. "Mapping The Proteome Of Streptococcus Gordonii." Thesis, The University of Sydney, 2005. http://hdl.handle.net/2123/5097.

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Streptococcus gordonii is a primary coloniser of the tooth surface where it efficiently ferments carbohydrates at pH levels above 6.0. By not being able to maintain the pH of dental plaque to a level required for enamel dissolution, the dominance of S. gordonii in dental plaque is considered a sign of a healthy oral cavity. However, upon entering the bloodstream and encountering a rise in pH, S. gordonii may become pathogenic, being one of the major causative organisms associated with infective endocarditis. Proteome analyses of S. gordonii grown at steady state in a chemostat allowed the phenotypic changes associated with alterations in pH levels characteristic of these two environments to be determined. As an initial starting point to this study, a two-dimensional electrophoresis (2- DE) reference map of S. gordonii grown at pH 7.0 was produced. Although only 50% of the S gordonii genome was available in an annotated form during the course of this study, the closely related Streptococcus pneumoniae genome (with which S. gordonii shares 97.24% DNA sequence homology) had been completed in 2001. The use of both of these databases allowed many of the S. gordonii proteins to be identified by mass spectrometry. Four hundred and seventy six protein spots, corresponding to 250 different proteins, or 12.5% of the S. gordonii proteome, were identified, giving rise to the first comprehensive proteome reference map of this oral bacterium. Of the 250 different proteins, 196 were of cellular origin while 68 were identified from the extracellular milieu. Only 14 proteins were common to both compartments. Of particular interest among the 54 uniquely identified extracellular proteins was a homologue of a peptidoglycan hydrolase that has been associated with virulence in S. pneumoniae. Among the other proteins identified were ones involved in transport and binding, energy metabolism, translation, transformation, stress response and virulence. Twelve cell envelope proteins were identified as well as 25 others that were predicted to have a membrane association based on the presence of at least one transmembrane domain. The study also confirmed the existence of 38 proteins previously designated as �hypothetical� or with no known function. Mass spectral data for over 1000 protein spots were accumulated and archived for future analysis when sequencing of the S. gordonii genome is finally completed. Following the mapping of the proteome of S. gordonii, alterations in protein spots associated with growth of the bacterium at pH intervals of 0.5 units in the pH range 5.5 - 7.5 were determined. Only 16 protein spots were shown to be significantly altered in their level of expression despite the range of pH studied. Among the differentially expressed proteins was a manganese-dependent inorganic pyrophosphatase (PpaC), which regulates expression of adhesins required for coaggregation. The expression of PpaC was highest at pH 6.5 - 7.0, the pH of a healthy oral cavity, indicating that PpaC may play an important part in dental plaque formation. Another differentially expressed protein was the heat-inducible transcription repressor (HrcA). Alterations in HrcA were consistent with its role as a negative repressor in regulating heat-shock proteins at low pH, even though no changes in the level of heat-shock proteins were observed as the pH declined. This result gave rise to the hypothesis that the possible reason cariogenic bacteria, such as Streptococcus mutans, can out compete S. gordonii at low pH might simply be due to their ability to manipulate their proteome in a complex manner for survival and persistence at low pH, unlike S. gordonii. This may imply some prevailing level of genetic regulation that is missing in S. gordonii.

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30

Stach, Christopher. "Characterizing the role of the enterotoxin gene cluster in Staphylococcus aureus diseases." Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/1909.

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Staphylococcus aureus is the leading cause of infective endocarditis in the United States. Infective endocarditis (IE) is defined as an infection of the endocardium, typically involving the heart valves. The hallmark features of IE are vegetations. Vegetations are cauliflower-like, stratified biofilms of bacteria and host factors that develop on the valve leaflets of the heart. The mechanisms of how vegetations form are not well understood, and as a consequence the bacterial factors that are important for development of IE are not well defined. My studies focus on the role of a family of S. aureus exoproteins known as superantigens and their role in IE. Superantigens (SAgs) are a class of secreted virulence factors that have been extensively studied for their role in systemic diseases such as toxic shock syndrome (TSS), pneumonia, and food poisoning. The SAg protein family is comprised of 23 distinct members designated as staphylococcal enterotoxin (SE) or enterotoxin-like (SEl) and toxic shock syndrome toxin-1 (TSST-1). The term superantigen is derived from the ability of SAgs to interact with the immune system, resulting in a nearly 3000-fold increase in activation when compared to standard antigens. SAgs have a defined structure that is composed of 2 domains, a carboxy-terminal beta-grasp domain and amino-terminal oligosaccharide/oligonucleotide binding (OB) fold. Defined groups of SAgs are associated with S. aureus strains isolated from specific diseases, but few studies have been done to determine the role of SAgs in diseases outside of TSS and food poisoning. The enterotoxin gene cluster (egc) is a group of 6 SAgs (selo, selm, sei, selu, seln, and seg) assembled into an operon-like cluster that is present in the majority of S. aureus strains isolated from IE patients. My studies have determined that the egc is able to induce vegetations when expressed in avirulent S. aureus strains. This is the first time the egc has been directly associated with IE. I further characterized the capacity of the individual egc proteins to induce vegetations. Four (selo, selm, sei, and selu) of the 6 egc SAgs were able to induce vegetation formation. This is the first time the individual egc proteins have been characterized and directly associated with IE. I also demonstrated that the egc proteins may not be exclusively expressed as a single polycistronic transcript but that selu and seg contain promoter elements that may drive their individual expression. Lastly, I provide evidence that the egc SAgs may be regulated by MgrA, a global regulator of S. aureus associated with virulence factor expression.

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Todt, Kendrea L., and S. P. Thomas. "A Phenomenological Exploration of the Lived Experience of Nurses Caring for Appalachians With Infective Endocarditis Associated With Intravenous Drug Use." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etsu-works/8484.

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32

Tubiana, Sarah. "Endocardite infectieuse : du risque à la prévention, de la cohorte clinique à la base médico-administrative." Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCC019/document.

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L’endocardite infectieuse (EI) est une maladie rare, de diagnostic difficile et de pronostic réservé. Staphylococcus aureus (SA) et les streptocoques oraux en sont les principaux microorganismes responsables. L’évaluation du risque de survenue de l’EI et l’amélioration des connaissances justifiant la stratégie de prévention nécessitent la mise en place de grandes cohortes cliniques et l’utilisation de bases médico-administratives. Chez les 2 008 patients (pts) présentant une bactériémie à SA de la cohorte multicentrique nationale VIRSTA, nous avons développé et validé un score prédictif d’EI comportant les caractéristiques initiales des pts et celles initiales et évolutives de la bactériémie. Les pts dont le score était ≤ 2 avaient un très faible risque d’EI (1% ; valeur prédictive négative [IC95%] = 99% [98;99]) comparés à ceux dont le score était ≥ 3, à risque d’EI élevé (17%) pour lesquels une échocardiographie devrait être effectuée. Utilisant la base médico-administrative du SNIIRAM, nous avons évalué la relation entre la pratique de gestes buccodentaires invasifs (GBDI) et la survenue d’EI à streptocoques oraux à partir d’une cohorte de 138 876 porteurs de prothèses valvulaires cardiaques ainsi que d’un plan expérimental de type case-crossover incluant 648 EI à streptocoques oraux. L’incidence d’EI à streptocoques oraux [IC95%] était de 93,7 pour 100 000 PA [82,4;104,9] sans augmentation significative du risque dans les 3 mois suivant un GBDI (RR= 1,25 [0,82;1,82]). Dans l’analyse case-crossover, la fréquence d’exposition à un GBDI dans les 3 mois précédent l’EI était faible mais plus élevée que lors de périodes contrôles antérieures (5,1% vs 3,2% ; OR : 1,66 [1,05;2,63]). Les GBDI pourraient contribuer au développement des EI à streptocoques oraux dans la population de pts porteurs de prothèses valvulaires cardiaques.La qualité des données de VIRSTA associée à la puissance du SNIIRAM ont permis l’identification des pts à risque d’EI à SA et la clarification de la contribution des GBDI dans les EI à streptocoques oraux
Infective endocarditis (IE) is a rare disease, difficult to diagnose, with high morbidity and mortality rates. Main involved microorganisms are Staphylococcus aureus and oral streptococci. Clinical research to improve IE risk assessment and IE prevention strategy requires the establishment of large clinical cohort studies and the use of medico-administrative databases. Using data from the multicenter French prospective VIRSTA cohort study on 2 008 adult patients (pts) with Staphylococcus aureus bloodstream infection (SAB), we have developed and validated an IE prediction score taking into account pts’ background and initial SAB characteristics. Pts with a score ≤ 2 had a very low risk of IE (1%, negative predictive value [95% CI] = 99% [98;99]) compared to those with a score ≥ 3, at higher risk of IE (17%) for whom an echocardiography is needed. Using the medico-administrative SNIIRAM database, we assessed the relation between invasive dental procedures (IDP) and oral streptococcal IE in a population-based cohort study of 138 876 pts with prosthetic heart valves and a case-crossover study including 648 pts with oral streptococcal IE. Incidence rate of oral streptococcal IE [95% CI] was 93.7 per 100 000 PA [82.4;104.9] without significant increase within the 3 months following IDP (RR = 1.25 [0.82;1.82]). In the case-crossover analysis, exposure to IDP was more frequent in the 3 months preceding IE than during previous control periods (5.1% vs. 3.2%, OR: 1.66 [1.05;2.63]). IDP may contribute to the development of oral streptococcal IE in pts with prosthetic heart valves.The quality of data from VIRSTA study combined with the power of SNIIRAM database made possible the identification of IE at-risk SAB pts and the evaluation of the IDP contribution in oral streptococcal IE

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Todt, Kendrea L., and S. P. Thomas. "The Lived Experience of Nurses Caring for Appalachian Patients Diagnosed With Infective Endocarditis Who Use or Have Used Intravenous Drugs: A Phenomenological Study." Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/etsu-works/8480.

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Todt, Kendrea L., and S. P. Thomas. "The Lived Experience of Nurses Caring for Patients Diagnosed With Infective Endocarditis Who Use or Have Used Intravenous Drugs in Appalachia: A Phenomenological Study." Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/etsu-works/8483.

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Walker, Jennifer Nicole. "The two-component system, ArlRS, regulates agglutination and pathogenesis in Staphylococcus aureus." Diss., University of Iowa, 2013. https://ir.uiowa.edu/etd/1414.

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Staphylococcus aureus is defined by its ability to agglutinate during exposure to human blood plasma. Although agglutination has long correlated with disease severity, the function of agglutination during infection remains unclear. Increasing evidence suggests the mechanisms of agglutination are highly complex and poorly understood. The goal of this dissertation was to characterize the mechanisms required for S. aureus agglutination in vitro and determine how these factors contribute to pathogenesis. Chapter II focuses on the development of two in vitro agglutination assays, which allow the process to be measured quantitatively. Through these assays, we confirmed the major factors contributing to agglutination are human fibrinogen and the bacterial surface protein, ClfA. Productive interactions between these two factors are required for agglutination to proceed. Surprisingly, we also identified a novel regulatory system that significantly contributed to agglutination. Inactivation of the ArlRS two-component system (TCS) prevents agglutination in both of the developed assays. Studies in Chapter III focused on characterizing the mechanism by which ArlRS inhibits agglutination. To examine regulation, quantitative PCR identified the major output of the ArlRS system as the gene ebh. Surprisingly, transcript levels of known extracellular matrix (ECM) binding proteins did not change. Characterization of ebh indicated that overexpression in an arlRS mutant is the major factor responsible for preventing agglutination. Deletion of ebh restores the ability of the arlRS mutant to agglutinate in both gravity and flow-based agglutination assays. Fluorescence microscopy of clumps indicates wildtype cells bind and incorporate fluorescently labeled human fibrinogen (Fg) displaying co-localization with the clumps. Surprisingly, arlRS mutants also bound human Fg, but these interactions were not productive for clumping, suggesting successful agglutination is more complex than binding ECM proteins. These studies indicate that ArlRS regulates agglutination through a unique mechanism that depends on the surface protein Ebh. Studies in Chapter IV were performed to determine the role ArlRS played in pathogenesis. A rabbit model of infective endocarditis and sepsis was employed to assess ArlRS virulence because this model has been shown to require agglutination for disease progression. Mutants in arlRS displayed reduced virulence in the rabbit model of infective endocarditis, which correlated with the mutant's inability to form a vegetation of the heart valve. These studies provide further insight into the importance of S. aureus agglutination during infection and define a mechanism of regulation through a novel surface protein.

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Smith, John L. "CONTRIBUTION OF A CLASS II RIBONUCLEOTIDE REDUCTASE TO THE MANGANESE DEPENDENCE OF Streptococcus sanguinis." VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/4936.

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Manganese-deficient Streptococcus sanguinis mutants exhibit a dramatic decrease in virulence for infective endocarditis and in aerobic growth in manganese-limited media. Loss of activity of a manganese-dependent, oxygen-dependent ribonucleotide reductase (RNR) could explain the decrease in virulence. When the genes encoding this RNR are deleted, there is no growth of the mutant in aerobic broth culture or in an animal model. Testing the contribution of the aerobic RNR to the phenotype of a manganese transporter mutant, a heterologous class II RNR from Lactobacillus leichmannii called NrdJ that requires B12 rather than manganese as a cofactor was previously introduced into an RNR mutant of S. sanguinis. Aerobic growth was only partially restored. Currently, we sought to improve NrdJ-dependent growth by (i) amending the medium to increase cellular levels of B12; (ii) characterizing a spontaneous mutant of the NrdJ-complemented strain with improved aerobic growth; and (iii) altering this strain through further genetic manipulation.

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Pizzi, María Nazarena. "Tomografía por emisión de positrones con 18F-fluordesoxiglucosa/Angio-Tomografía cardíaca (PET/CTA) en pacientes con sospecha de endocarditis infecciosa: Utilidad diagnóstica e impacto en las decisiones terapéuticas." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/667481.

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La endocarditis infecciosa (EI) es una patología grave que continúa teniendo mal pronóstico a pesar de los avances en el tratamiento médico y quirúrgico y cuyo diagnóstico es siempre un desafío clínico. De la misma manera, la infección de dispositivos intracardíacos es un problema creciente que también comporta una alta morbimortalidad y que posee importantes dificultades diagnósticas. Por este motivo el desarrollo de una nueva técnica de imagen que contribuya a mejorar la detección de estas patologías constituye un tema de relevancia en el momento actual. La presente tesis doctoral se compone de dos artículos que analizan diferentes aspectos de la utilidad de la tomografía por emisión de positrones con 18F-fluordesoxiglucosa/ Angiotomografía computarizada cardíaca (18F-FDG-PET/CTA (PET/CTA) para el diagnóstico de EI y la infección de dispositivos intracardíacos. El primer artículo demuestra que que el PET-CT/CTA es una técnica útil en el diagnóstico de los pacientes con sospecha de EI portadores de válvulas protésicas o dispositivos intracardíacos y que la combinación de sus hallazgos con los Criterios de Duke modificados mejora la sensibilidad diagnóstica del 52% al 90,7% permitiendo establecer un diagnóstico concluyente en el 95% de los casos en esta población de enfermos. Asimismo, demuestra que la combinación de la gran sensibilidad para detectar inflamación de la 18F-FDG-PET/CT con la alta resolución espacial del CTA cardíaco para definir el daño estructural es la mejor estrategia para el diagnóstico y la detección de complicaciones periprotésicas, con resultados superiores al PET/CT convencional (sensibilidad diagnóstica del 88,6% para la combinación de los Criterios de Duke y los estudios de PET/CT sin contraste y del 91% para la combinación de los primeros con el PET/CTA). El segundo artículo aborda la utilidad de esta técnia en un grupo particularmente complejo de pacientes adultos con cardiopatías congénitas y portadores de materiales protésicos, observándose también un incremento de la sensibilidad diagnóstica en estos últimos del 39,1% al 87%, con un diagnóstico concluyente en el 92% de los casos. Dicho incremento representa un impacto superior al demostrado en la población general. En forma adicional y en ambos grupos, el PET-CT/CTA permitió documentar eventos embólicos y metástasis sépticas en un 15% de los casos, identificó la puerta de entrada de la bacteriemia en casos concretos y ofreció un diagnóstico alternativo en el 54% de los casos de EI o infección de dispositivos intracardíacos rechazadas.
Infectious endocarditis (IE) is a serious pathology that continues to have a poor prognosis despite advances in medical and surgical treatment and its diagnosis poses always a clinical challenge. In the same way, the infection of intracardiac devices is a growing problem that also entails a high morbidity and mortality and that has important diagnostic difficulties. For this reason, the development of a new imaging technique that contributes to improve the detection of these pathologies is an issue of relevance at the present time. This doctoral thesis is composed of two articles that analyze different aspects of the usefulness of the positron emission tomography with 18F-fluorodeoxyglucose/cardiac computed tomography (18F-FDG-PET/CTA (PET CTA) for the diagnosis of IE and the infection of intracardiac devices. The first article shows that PET-CT/CTA is a useful technique in the diagnosis of patients with suspected prosthetic valve IE or intracardiac device infection and that the combination of its findings with the modified Duke Criteria improves the diagnostic sensitivity from 52% to 90.7%, making it possible to establish a conclusive diagnosis in 95% of the cases in this patient population. Besides, it demonstrates that the combination of the high sensitivity of the 18F-FDG-PET/CT to detect inflammation with the high spatial resolution of the cardiac CTA to define structural damage is the best strategy for the diagnosis and the detection of periprosthetic complications, with superior results to the conventional PET/CT technique (diagnostic sensitivity of 88.6% for the combination of the Duke Criteria and non-enhance PET/CT and 91% for the combination of the former with the PET/CTA). The second article addresses the usefulness of this technique in a particularly complex group of adult patients with congenital heart disease that have several prosthetic materials also observing an increase in the diagnostic sensitivity in this specific cohort, from 39.1% to 87%, with a conclusive diagnosis in 92% of the cases. This increase represents a greater impact than that observed in the general population. Additionally and in both groups, the PET-CT/CTA allowed the detection of embolic events and septic metastases in 15% of the cases, identified the source of the bacteremia in some specific cases and elucidated an alternative diagnosis in 54% of the rejected IE or device infection cases.

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Bouchiat, Coralie. "Facteurs bactériens impliqués dans la survenue de l’endocardite infectieuse au cours d’une bactériémie à Staphylococcus aureus." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10187.

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L'endocardite infectieuse (EI) est une complication rare mais gravissime de la bactériémie à Staphylococcus aureus. Bien que certains facteurs de risque liés à l'hôte aient été décrits, l'implication de facteurs bactériens dans la survenue de l'EI est encore inconnue. Ces travaux de thèse ont visé à chercher tout élément bactérien associé à l'EI. Les facteurs phénotypiques décrits ou supposés comme potentiellement impliqués dans l'EI ont été testés. En parallèle, les profils génotypiques des souches obtenus par puces ADN ont été analysés par différents outils statistiques. L'analyse statistique univariée n'a montré aucune différence significative entre souches d'EI et souches de bactériémie, suggérant un processus complexe et multifactoriel. En effet, l'analyse discriminante en composante principale appliquée sur les données de puces ADN a permis de mettre en évidence une distinction entre les deux groupes de souches, confirmée sur une collection indépendante de souches. De plus, une fonction linéaire simplifiée, basée sur seulement 8 marqueurs génétiques, a permis d'obtenir des performances similaires, sur la collection de souches initiale ainsi que la collection indépendante de validation. En dernier lieu, les souches d'EI et de bactériémie ont été comparées à partir de séquences du génome complet (n = 40 (20 EI, 20 bactériémies)). L'analyse statistique par analyse discriminante en composante principale réalisée sur ces données génomiques confirme une distinction possible entre les deux groupes de souches. Au total, ces travaux de thèse apportent la preuve de concept que les facteurs bactériens sont impliqués dans la survenue de l'EI au cours de bactériémie à S. aureus
Infective endocarditis (IE) is a severe condition complicating 10-25% of Staphylococcus aureus bacteremia. Although host-related IE risk factors have been identified, the involvement of bacterial features in IE complication is still unclear. This PhD work aimed to characterize strictly defined IE and bacteremia isolates and searched for discriminant features. Phenotypic traits previously reported or hypothesized to be involved in staphylococcal IE pathogenesis were tested. In parallel, the genotypic profiles of all isolates, obtained by microarray, were analyzed. No significant difference was observed between IE and bacteremia strains, regarding either phenotypic or genotypic univariate analyses, suggesting a multifactorial process. However, the discriminant analysis of principal components (DAPC), applied on microarray data, segregated IE and bacteremia isolates. The performance of this model was confirmed with an independent collection of IE and bacteremia isolates. Finally, a simple linear discriminant function based on a subset of 8 genetic markers retained valuable performance both in study collection and in the independent validation collection. At last, IE and bacteremia isolates were compared based on whole genome sequence data from a subset of 40 isolates. When applied to this dataset, DAPC confirmed a possible segregation between the two groups of isolates. All in all, this PhD work provides the proof of concept that bacterial characteristics may contribute to the occurrence of IE in patients with S. aureus bacteremia

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Spivack, Stephanie. "The Care of Hospitalized Intravenous Drug Users in 2019." Master's thesis, Temple University Libraries, 2019. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/553776.

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Urban Bioethics
M.A.
People who inject drugs, particularly opioids, are a growing population, especially in North Philadelphia. This population is at high risk for medical complications that require hospitalization. While hospitalized, this population poses unique challenges to the healthcare system, including high costs and readmission rates, as well as stress and burnout among providers and staff. These patients are at high risk of discharges against medical advice because of complicated social factors as well as inadequate recognition of pain and withdrawal. As the opioid epidemic evolves, previous strategies for managing these patients, which traditionally relied on referral to psychiatry or social work in addition to symptomatic treatment, need to be re-evaluated. Ethically, the decision-making capacity of these patients is frequently called into question, and there is a difficult-to-strike balance between respecting their autonomy and acting with beneficence to provide the best care. There are also public health concerns that come into play. Better acknowledgment of the issues that this population faces, and better management of pain and withdrawal, may improve their outcomes, as well as reduce provider stress and burnout.
Temple University--Theses

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Harshman, D. K., B. M. Rao, J. E. McLain, G. S. Watts, and J. Y. Yoon. "Innovative qPCR using interfacial effects to enable low threshold cycle detection and inhibition relief." AAAS, 2015. http://hdl.handle.net/10150/621255.

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UA Open Access Publishing Fund
Molecular diagnostics offers quick access to information but fails to operate at a speed required for clinical decision-making. Our novel methodology, droplet-on-thermocouple silhouette real-time polymerase chain reaction (DOTS qPCR), uses interfacial effects for droplet actuation, inhibition relief, and amplification sensing. DOTS qPCR has sample-to-answer times as short as 3 min 30 s. In infective endocarditis diagnosis, DOTS qPCR demonstrates reproducibility, differentiation of antibiotic susceptibility, subpicogram limit of detection, and thermocycling speeds of up to 28 s/cycle in the presence of tissue contaminants. Langmuir and Gibbs adsorption isotherms are used to describe the decreasing interfacial tension upon amplification. Moreover, a log-linear relationship with low threshold cycles is presented for real-time quantification by imaging the droplet-on-thermocouple silhouette with a smartphone. DOTS qPCR resolves several limitations of commercially available real-time PCR systems, which rely on fluorescence detection, have substantially higher threshold cycles, and require expensive optical components and extensive sample preparation. Due to the advantages of low threshold cycle detection, we anticipate extending this technology to biological research applications such as single cell, single nucleus, and single DNA molecule analyses. Our work is the first demonstrated use of interfacial effects for sensing reaction progress, and it will enable point-of-care molecular diagnosis of infections.

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Rubio, Pachas Lolo Arnold. "Perfil clínico, espectro microbiológico, evolución y factores pronósticos en pacientes con endocarditis infecciosa en el Instituto Nacional del Corazón." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2009. https://hdl.handle.net/20.500.12672/2529.

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La Endocarditis Infecciosa (EI) como tal fue descrita por primera vez en 1885, por Osler; las variables relacionadas con su diagnóstico: cardiopatía predisponente, bacteriemia, fenómeno embólico cutáneo o visceral y el proceso endocárdico activo, permanecen como eventos clínicos fundamentales hasta la actualidad. Su definición continúa presuponiendo: Una lesión del endotelio, seguida de depósito de plaquetas y fibrina, dependiente del proceso de coagulación generalmente debido a un flujo anormal, o sea una cardiopatía predisponente; luego la adhesión de un microorganismo al depósito, siendo este el proceso endocárdico activo y por ultimo manifestaciones clínicas compatibles con una enfermedad infecciosa, es decir fiebre, escalofríos y mal estado general, con o sin la presencia de un fenómeno embólico.
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Parraga, Paucar Patricia Lorena. "Pulpotomía con electrocauterio en paciente con endocarditis bacteriana." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2019. https://hdl.handle.net/20.500.12672/11232.

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Evalúa la técnica de Electrocauterio como alternativa para tratamiento de pulpotomía y sus beneficios. La atención de tratamiento integral en sala de operaciones en paciente de 6 años del Servicio de Cardiología del INSN, con Diagnostico de Endocarditis bacteriana, se realizó dos pulpotomias en dientes deciduos con electrocauterio, se colocó base Oxido de Zinc + Eugenol, luego se colocó Ionómero de vidrio y resina fotocurable con técnica incremental. La respuesta de las piezas tratadas con Electrocauterio fue favorable clínica y radiográficamente. Se concluye que al considerar al Electrocauterio como tratamiento no farmacológico alternativo.
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MIKOLAJCZAK, NATHALIE. "Les endocardites fongiques : a propos de trois observations." Lille 2, 1994. http://www.theses.fr/1994LIL2M326.

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Aguirre, Montes Patricia Milagros. "Nivel de conocimiento sobre Profilaxis Antibiótica de Endocarditis Infecciosa previa a procedimientos odontológicos en internos de odontología de tres universidades de Lima - 2013." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2014. https://hdl.handle.net/20.500.12672/3521.

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El siguiente estudio fue de tipo descriptivo, transversal, se realizó con el objetivo de determinar el Nivel de conocimiento sobre Profilaxis Antibiótica de Endocarditis Infecciosa previa a procedimientos odontológicos en internos de odontología. La muestra fue estratificada, constituida de 117 internos de tres universidades de Lima que se encontraban finalizando su internado hospitalario correspondiente en el año 2013. Para determinar el nivel de conocimiento se realizó una revisión bibliográfica y se elaboró una encuesta/cuestionario que constaba de 20 preguntas cerradas que fue validado mediante juicio de expertos. El instrumento evaluó el nivel de conocimiento de cuatro secciones: Epidemiologia, etiopatogenia, indicación y farmacología de profilaxis antibiótica para prevenir EI en pacientes de riesgo previa a procedimientos odontológicos y los califico como bajo regular y alto, según la escala establecida. El 53,85% de los estudiantes participantes de la investigación tenían un nivel bajo de conocimientos sobre profilaxis antibiótica de endocarditis infecciosa previo a procedimientos odontológicos. En el nivel de conocimientos, regular, se distribuyó el 32.48% de la población y en el nivel de conocimientos, bueno, se encontró el 13,68% de la población. Las secciones donde los internos obtuvieron los mayores puntajes fueron epidemiologia de Endocarditis Infecciosa y farmacología de la profilaxis antibiótica de EI. En cambio las secciones de etiopatogenia de EI e indicación de profilaxis antibiótica fueron donde se obtuvieron los menores puntajes. Con el estudio se concluye que existe un déficit en el conocimiento sobre profilaxis antibiótica para prevenir EI en pacientes de riesgo previo a procedimientos odontológicos y que se deben de tomar medidas educativas para mejorar los aspectos que muestran necesidades de aprendizaje, debido a la importancia del rol que cumplen los odontólogos en la prevención de esta potencialmente mortal infección, en beneficio de la población que podrán serán atendido por los futuros odontólogos.
*** The following study was descriptive, cross-sectional, was conducted to determine the level of knowledge of Infective Endocarditis Antibiotic prophylaxis prior to dental procedures in dentistry inmates. The sample was stratified, consisting of 117 inmates from three universities in Lima who were ending their corresponding hospital internship in 2013. To determine the level of knowledge was conducted a literature review and a survey /questionnaire consisted of 20 closed questions was developed and was validated by expert judgment. The instrument assessed the level of knowledge of four sections: Epidemiology, pathogenesis, pharmacology and indications for antibiotic prophylaxis to prevent IE in patients at risk prior to dental procedures and qualify as under regular and high, according to the scale set. 53.85% of students research participants had a under level of knowledge on antibiotic prophylaxis of infective endocarditis prior dental procedures. At the level of knowledge, regular, was circulated on 32.48% of the population and the level of knowledge, high, found 13.68% of the population. The sections where the inmates obtained the highest scores were Infective Endocarditis epidemiology and pharmacology of antibiotic prophylaxis of IE. Instead sections pathogenesis of EI and indication for antibiotic prophylaxis were where lower scores were obtained. With the study concludes that there is a deficit in knowledge about antibiotic prophylaxis to prevent IE in patients at risk prior to dental procedures and should be taking steps to improve educational aspects that show learning needs, because of the importance of the role that dentists in preventing this potentially fatal infection, the benefit of the population that will be served by future dentists
Tesis

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Sauvage, Christine. "Corynebacterium multi-resistants aux antibiotiques : etude bacteriologique et clinique a propos d'un cas d'endocardite a corynebacterium du groupe d2 a point de depart urinaire." Université Louis Pasteur (Strasbourg) (1971-2008), 1990. http://www.theses.fr/1990STR1M062.

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Ries, Johannes. "Pneumococcal pili and other cell surface properties affect the infection biology of Streptococcus pneumoniae /." Stockholm, 2007. http://diss.kib.ki.se/2007/978-91-7357-179-1/.

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Oliveira, Júlio César de. "Estudo prospectivo e randomizado de profilaxia antimicrobiana para procedimentos cirúrgicos em estimulação cardíaca artificial." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/5/5131/tde-19022009-112208/.

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O objetivo desse estudo foi avaliar os efeitos da administração prévia de antibiótico na incidência de complicações infecciosas em procedimentos de estimulação cardíaca artificial. Os pacientes foram selecionados em um estudo duplo-cego e randomizado (1:1). Grupo I Cefazolina (1,0g dose única) versus grupo II placebo. O comitê de segurança interrompeu o estudo após a inclusão de 649 pacientes devido à diferença entre os grupos (group I 314; grupo II 335 pacientes) em favor do uso de antibiótico: 2 infectados (0,63%) versus 11 infectados no grupo placebo (3,28%); p=0,016. Marcadores identificados por análise univariada: não uso de antibiótico; procedimentos de implantes (versus trocas); hematoma pós-operatório e duração do procedimento. O não uso de antibiótico e hematoma pós-operatório foram significantes em análise multivariada
The objective of this study was to evaluate the effects of the previous venous antibiotic administration in the incidence of infectious complications in cardiac stimulation surgical procedures. Patients were selected in a double blind, randomized (1:1) trial. Group I Cefazolin (1,0g one dose) versus group II placebo. The security committee interrupted the trial after inclusion of 649 patients due to differences between groups (group I 314; group II 335 patients) in favor of the antibiotic arm: 2 infected patients (0,63%) versus 11 infected patients in the placebo arm (3,28%); p=0,016. Markers identified by univariate analysis: non-use of preventive antibiotic; implant procedures (versus replacement); post-operative haematoma and procedure duration. The non-use of antibiotic and the post-operative haematoma were independent predictors of infection in multivariate analysis

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Ben, Amara Amira. "Cellules placentaires et infection par coxiella burnetii." Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX20687/document.

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La fièvre Q se traduit par de graves conséquences obstétricales chez la femme enceinte. La voie principale de la contamination humaine par Coxiella burnetii, l’agent de la fièvre Q, est constituée des aérosols provenant des placentas d’animaux infectés. La nature des cellules placentaires cibles de C. burnetii reste totalement inconnue. J’ai montré que C. burnetii infecte les trophoblastes des lignées BeWo et JEG et que les bactéries se répliquent fortement dans les cellules BeWo et survivent dans les cellules JEG. Une analyse par microarray montre que C. burnetii induit une réponse inflammatoire dans les cellules BeWo qui lui est spécifique. Ces résultats suggèrent que les trophoblastes pourraient constituer une niche pour C. burnetii. Les macrophages placentaires pourraient également servir de réservoir pour C. burnetii. J’ai montré que les macrophages placentaires CD14+ sont des macrophages qui présentent des caractéristiques phénotypiques, transcriptionnelles et fonctionnelles différentes de celles des monocytes circulants et des macrophages dérivés de monocytes. Ils forment en outre des cellules géantes multinucléées qui pourraient réguler l’activité cytolytique des macrophages dans le contexte placentaire puisque les macrophages placentaires CD14+ ne sont ni de type M1 ni de type M2
In pregnant women Q fever presents obstetrical complications. The principal way of human contamination by Coxiella burnetii, the agent of Q fever, is due to aerosols from placentas of infected animals. The nature of placenta cells that are targeted by C. burnetii remains unknown. I showed that C. burnetii infects BeWo and JEG trophoblastic cells and that organisms intensively replicated in BeWo cells and survived in JEG cells. A microarray analysis showed that C. burnetii induced a specific inflammatory response in BeWo cells. These results suggest that trophoblasts may serve as a reservoir for C. burnetii. Placenta macrophages placentaires may also targeted by C. burnetii. I showed that placenta CD14+ macrophages were characterized by phenotypic, transcriptional and functional properties different from those of circulating monocytes and monocyte-derived macrophages. In addition, placenta CD14+ macrophages differentiate into multinucleated giant cells that may regulate the cytolytic activity of macrophages in the placenta context since placenta CD14+ macrophages were not polarized in M1 or M2 macrophages. While M1/M2 polarization of macrophages is well established, that of monocytes remains an important question. We activated monocytes with canonical agonists of M1 and M2 profiles in macrophages using microarrays. The early response, 6 hours, of monocytes corresponded to a type M1/M2 response but the delayed response, 18 hours, did not correspond to the M1/M2 dichotomy, demonstrating a new level of heterogeneity of myeloid cells

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Grzybinski, Sarah. "Prognostic factors in infective endocarditis." Thesis, 2016. https://hdl.handle.net/2144/19176.

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BACKGROUND: Infective endocarditis (IE) is an infectious disease, most often bacterial in etiology, which affects the endocardial tissue layer of the heart. Despite advances in diagnostic technology, surgical technique, and antimicrobial therapy, IE remains a high-mortality disease. OBJECTIVE: This is a proposed quality improvement initiative for the Boston Medical Center (BMC) inpatient medicine service. The initiative aims to identify predictors of mortality in patients with IE, and then use the predictors to create a mortality risk-assessment checklist. The checklist will serve as a clinical tool for medicine service providers to help determine if upgrade to ICU level of care is warranted. With early upgrade to an ICU setting, patients with a high risk of mortality will receive more individualized care and expedited medical intervention. The goal of this quality improvement initiative is to decrease mortality rate in patients with IE at BMC. METHODS: This quality improvement initiative will implement the PDSA (plan, do, study, act) model for quality improvement. The checklist will be integrated into the electronic health record system at BMC and will be implemented over a two-year time period. Each PDSA cycle will last one year, and between PDSA cycles the checklist will be modified according to medical provider feedback. The data will be gathered through chart reviews to determine pre and post-checklist differences in number of transfers to the ICU and overall mortality rates of IE patients at BMC. RESULTS: The literature review of this proposed quality improvement initiative has identified nine independent risk factors for mortality in patients with IE: Staphylococcus aureus as infective organism, New York Heart Association class IV heart failure, left ventricular ejection fraction < 40%, vegetation size ≥ 15 mm, age > 50 years, diabetes mellitus, peripheral dermatologic findings on physical examination, serum neutrophil-to-lymphocyte ratio > 5.45, and serum D-dimer level > 4.0 mg/L. CONCLUSION: If medical providers had access to a risk assessment tool to help identify IE patients with a high risk of mortality, they could more accurately determine appropriate level of care, expedite medical intervention, and possibly reduce rates of in-hospital death in patients with IE.

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Chen, Ya-Hsin, and 陳雅昕. "Role of Ahp in Streptococcus mutans-induced infective endocarditis." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/ywnf2u.

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碩士
國立臺灣大學
口腔生物科學研究所
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Infective endocarditis (IE) is an infectious disease of the cardiovascular system, and carries a high recurrence and mortality rate. Streptococcus mutans, a member of viridans streptococci, is a commensal in the oral cavity and also one of major opportunistic pathogen for causing IE. Escaping immune surveillance and forming biofilm are two determining virulent factors for bacteria to cause IE. Our previous reports demonstrated that one S. mutans protein, AtlA, not only plays the role in enhancing bacterial resistance against neutrophil killing through binding fibronectin in the plasma, but also contributes to bacterial biofilm formation on the heart valve through mediating extracellular DNA release. Interestingly, we identified a AtlA homologous protein (named Ahp) by using polyclonal antibodies against AtlA. Therefore, we hypothesized Ahp may also play similar roles in modulating S. mutans virulence in biofilm formation and immune evasion. By using in vivo rat experimental IE model, we demonstrated the role of Ahp in the pathogenesis of IE. In vitro assays showed that Ahp majorly plays role in mediating bacterial ability to escape neutrophil killing. More interestingly, we found that S. mutans strains can be grouped into two types according to the intactness of Ahp. When the strain UA159, which originally exhibits the truncated form of Ahp, expresses the intact Ahp, its virulence for causing IE will be dramatically increased. The clinical blood isolates of S. mutans with the intact form of Ahp also exhibit higher abilities to escape immune surveillance and cause IE. These data suggested that Ahp mediates S. mutans to escape neutrophil killing, which contributes to the pathogenesis of IE.

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