Academic literature on the topic 'Clostridium difficile – Western Australia – Etiology'

SUMMARYThe incidence ofClostridium difficile-associated diarrhoea (CDAD) was investigated retrospectively at a 690-bed teaching hospital for the period 1983–92. Our aims were to determine: (i) the distribution by age and sex of patients with CDAD, (ii) the possibility of a seasonal trend and, (iii) the influence of infection control procedures, contamination of the hospital environment and the use of third-generation cephalosporins. The laboratory diagnosis of CDAD was based on demonstration of the organism by stool culture and/or detection of specific cytotoxin in stool filtrates.C. difficilewas detected in 917 patients who were being investigated for diarrhoeal illness. Yearly isolations varied from a low of 49 in 1983 to a high of 120 in 1990 (Chi square for linear trend 128·8;P <0·005). Most patients were elderly, with 63% aged 60 years or more; the majority (59%) were female. The relationship between culture ofC. difficileand detection of cytotoxin in faecal extracts was also examined. Sixty percent of a sample of 132 isolates from patients in whom faecal cytotoxin was not detected produced cytotoxinin vitro, suggesting that culture is a more sensitive indicator of infection withC. difficilethan cytotoxin detection. When the total number of faecal specimens received in the laboratory was used as a denominator there was an increase in the number of incident cases of CDAD between 1983 and 1990, apart from 1986. When occupied bed days was used as the denominator a similar trend was observed with a peak in 1990. These increases correlated with an increase in the use of third-generation cephalosporins at SCGH between 1983 and 1989 (Pearson's correlation coefficient, 0·90). The introduction of Body Substance Isolation in 1989, in conjunction with other infection control procedures, appears to have halted the rise, despite a continuing use of broad-spectrum cephalosporins. In order to reduce the number of cases of CDAD, either a reduction in levels of environmental contamination or a reduction in the use of third-generation cephalosporins is required. If this can be achieved the economic consequences, in terms of an opportunity cost, will be considerable.

Clostridium difficile is now recognised as the major cause of hospital acquired infectious diarrhoea. Data from Sir Charles Gairdner Hospital (SCGH) in Perth, Western Australia, is typical of many similar hospitals in developed countries. SCGH is a 600 bed adult university teaching hospital. During the period 1983 to 1992, C. difficile was detected in 917 patients who were being investigated for diarrhoeal illness. Up to 120 patients a year were infected, most of these being elderly females. Incidence rates increased from 23/100,000 occupied bed days in 1983 to 56/100,000 occupied bed days in 1990.

ABSTRACTRecently,Clostridium difficilehas been isolated from a wide variety of animals, particularly production animals, mainly cattle and pigs. Concurrently, the incidence ofC. difficileinfection (CDI) in humans has increased in the community, with some suggestions that food-borne transmission ofC. difficileis occurring. Interestingly, sheep and lambs appear not to have been investigated for carriage/colonization withC. difficile. The aim of this project was to determine the prevalence of carriage ofC. difficilein sheep and lambs in Australia by culturing fecal samples. A total of 371 sheep and lamb fecal samples were received in seven batches from three different geographic areas in eastern Australia and two in Western Australia. The overall rate of detection in sheep and lambs was low (4.0%); however, carriage/colonization in lambs (6.5%) was statistically significantly higher than that in sheep (0.6%) (P= 0.005). Seven distinct PCR ribotype patterns were observed, three of which were known international ribotypes (UK 056 [n= 1], UK 101 [n= 6], and UK 137 [n= 2]), while the remainder were unable to be matched with our available reference library. This low rate of carriage/colonization in Australian ovines suggests they are unlikely to be a major source/reservoir of human infections.

ABSTRACT In recent years, community-associated Clostridium difficile infection (CA-CDI) has emerged as a significant health problem, accounting for ∼50% of all CDI cases. We hypothesized that the home garden environment could contribute to the dissemination of C. difficile spores in the community and investigated 23 homes in 22 suburbs of Perth, Western Australia. We identified a high prevalence of toxigenic C. difficile in this environment. In total, 97 samples consisting of soil (n = 48), compost (n = 15), manure (n = 12), and shoe sole swabs (n = 22) were collected. All samples were cultured anaerobically on C. difficile ChromID agar and enriched in brain heart infusion broth, and isolates were characterized by toxin gene PCR and PCR ribotyping. Two-thirds (67%; 95% confidence interval [CI], 57 to 76%) of home garden samples, including 79% (95% CI, 68 to 91%) of soil, 67% (95% CI, 43 to 90%) of compost, 83% (95% CI, 62% to 100%) of manure, and 32% (95% CI, 12 to 51%) of shoe sole samples, contained C. difficile. Of 87 isolates, 38% (95% CI, 28 to 48%) were toxigenic, and 26 PCR ribotypes (RTs), 5 of which were novel, were identified. The toxigenic C. difficile strain RT014/020 was the most prevalent RT. Interestingly, 19 esculin hydrolysis-negative strains giving white colonies were identified on C. difficile ChromID agar, 5 of which were novel toxigenic RTs that produced only toxin A. Clearly, there is the potential for transmission of C. difficile in the community due to the contamination of home gardens. Our findings highlight the importance of a “One Health” approach to dealing with CDI. IMPORTANCE Recently, community-associated Clostridium difficile infection (CA-CDI) has emerged as a significant problem, accounting for ∼50% of all CDI cases and reported to affect a younger population without traditional risk factors. Possible sources of CA-CDI are soil, food, and water contaminated by animal feces, and recent reports show overlapping ribotypes of C. difficile in animals, humans, and the environment; however, the epidemiology of CA-CDI and related risk factors need to be better understood. Our research aimed to determine the prevalence of C. difficile in home gardens and on the shoe soles of homeowners in Perth, Western Australia. There were high rates of contamination with C. difficile in gardens, and some of the ribotypes identified had been isolated from human cases of CDI in Western Australia. This study shows that home gardens and shoes may be a source of C. difficile in CA-CDI.

[Truncated abstract] The prinicipal aim of this thesis was to explore the relationship between 3rd generation cephalosporin antibiotics and hospital-acquired Clostridium difficile-associated diarrhoea (CDAD). This antibiotic class has been implicated in the aetiology of CDAD; therefore restriction of these antibiotics via antibiotic policies represents a potential strategy for prevention and control of CDAD. Successful control of CDAD in hospitals translates to improved quality of care for patients, and a reduction of pressure on hospital resources. Therefore, the objectives of this study were to determine whether 3rd generation cephalosporins were related to CDAD, to evaluate the effect of changes to antibiotic policy on the incidence of CDAD, and to determine the impact of CDAD on patient length of stay and hospital costs. The study was conducted in Sir Charles Gairdner Hospital (SCGH), a public teaching hospital located in Perth, the capital city of the state of Western Australia. Evidence for an association between 3rd generation cephalosporins and CDAD was obtained from studies of ecologic- and individual-level data. A time series analysis of the relationship between monthly consumption of 3rd generation cephalosporins and the incidence of CDAD in SCGH was undertaken covering the period 1994 to 2000. The results demonstrated a positive relationship between the use of 3rd generation cephalosporins and CDAD. A matched case-control study that involved 193 adult inpatients diagnosed with CDAD and 386 adult inpatients without CDAD, selected from the period 1996 to 2000, was conducted. Information was collected on exposure to 3rd generation cephalosporin antibiotics during hospitalisation, as well as exposure to other antibiotics and medications, procedures, and comorbidities. Results from conditional logistic regression analyses found CDAD cases were six times more likely to be exposed to 3rd generation cephalosporins during their admission, prior to the onset of diarrhoea, than controls (adjusted odds ratio [OR] = 6.17, 95% confidence interval [CI] = 1.56-24.37). Approximately one third of CDAD in the study population could be attributed to 3rd generation cephalosporins. CDAD cases were also four times more likely to have been exposed to either amoxicillin-clavulanate or ticarcillin-clavulanate (adjusted OR=4.23, 95% CI=1.81-9.93). In October 1998, an antibiotic policy was introduced at SCGH that restricted the use of ceftriaxone, the 3rd generation cephalosporin most commonly used by the hospital. During 1999 and 2000, the incidence of CDAD halved as ceftriaxone consumption fell in response to this policy. The effect of this policy was demonstrated in the time series model; during the post-policy period the relationship between ceftriaxone and CDAD that was evident prior to the policy was cancelled out. From the individual-level data, obtained from the case-control study, a reduction in the prevalence of exposure to 3rd generation cephalosporins from 11% to 1% accounted for a 30% reduction in the incidence of CDAD. Data from the case-control study was also used to analyse the independent contribution of CDAD to length of stay and admission costs using multiple linear regression