Enterotoxigenic Clostridium perfringens infection and pediatric patients with inflammatory bowel disease.

BACKGROUND AND AIMS: Clostridium difficile is the major cause of antibiotic-associated diarrhea and is the most well known bacterial pathogen associated with inflammatory bowel disease (IBD). Enterotoxigenic Clostridium perfringens has also been detected in up to 15% of antibiotic-associated diarrhea cases, and it has not been found in healthy people. The aim of this study was to investigate the prevalence of C. perfringens infection in pediatric patients with IBD. METHODS: This was a prospective, controlled study evaluating pediatric IBD patients in the Department of Pediatric Gastroenterology and Nutrition in Warsaw, Poland. All of the patients were diagnosed according to the Porto criteria. There were two control groups: (1) non-IBD patients that were suspected for bacterial diarrhea and (2) healthy children. Stool samples were collected on the day of admission. C. perfringens infection diagnosis was based on a positive stool enzyme immunoassay (C. perfringens enterotoxin test kit TechLab). RESULTS: 91 fecal specimens from patients with IBD were collected. The average patient age was 11.7 years in IBD group, 7.4 years in non-IBD patients with diarrhea, and 7.4 years in healthy children. The prevalence of C. perfringens infection was 9% (8/91; CI 95% 4.6-16.4). There were more Crohn's patients (6/8) in the C. perfringens positive group. There was no C. perfringens infection in the two control groups. CONCLUSION: Our pilot data add evidence to the hypothesis that Clostridia other than C. difficile may play a significant role in the clinical course of IBD. However, further studies are needed to confirm this.

[Assessment of the usefulness of chromogenic medium for the isolation of Clostridium difficile from the gastrointestinal tract of children with diarrhoea]. / Ocena przydatnosci podloza chromogennego do izolacji Clostridium difficile z przewodu pokarmowego dzieci z biegunka.

INTRODUCTION: Clostridium difficile is well known as an important cause of nosocomial infection. Laboratory diagnostics have included bacterial culture or more commonly, direct detection of preformed toxin in stool samples using different assays. The aim of this study was to evaluate and compare two selecitve media to isolation of C. difficile from paediatric diarrhoeal stool samples. METHODS: Fifty nine stool samples, collected from 43 children with diarrhoea, were examined for routine laboratory diagnosis of C. difficile infection. Commercially available tests for detection of A/B toxins of C. difficile were performed. The same stool samples were cultured on two selective media for strain isolation: CLO and CDIFF (bioMerieux S.A., France) and incubated 48h and 24h respectively. RESULTS: Twenty two samples gave positive results for toxins A/B C. difficile. From 24 samples inoculated on selective media C. difficile strains were cultured: from 8 samples on CLO medium and from 16 samples on CDIFF medium. CONCLUSIONS: CDIFF medium is more effective for isolation of C. difficile strains from stool samples collected from children with diarrhoea.

[Characteristic of clinical strains of gram-negative obligate anaerobes]. / Charakterystyka klinicznych szczepów gram-ujemnych bezwzglednych beztlenowców.

The aim of the study was to assess prevalence and antibiotic susceptibility profiles ofGram-negative strictly anaerobic bacteria isolated from clinical specimens taken from hospitalized patients in 2005-2006. Biochemical identification and antibiotic susceptibility were done in an automated system ATB Expression (bioMerieux sa). From 12262 specimens examined 867 strains of obligate anaerobes were isolated. Gram-negative strictly anaerobic bacteria were cultured in number of 138 strains (15,9%). All cultures were performed on Columbia agar and Schaedler agar media (bioMerieux sa) supplemented with 5% sheep blood and incubated at 37 degrees C for 48-120 h in 85% N2, 10% H2, 5% CO2. Most frequently isolated was Bacteroides spp. (41,3%). For this group beta-lactamase activity was evaluated by using nitrocefin disc test (Cefinase BBL, Becton Dickinson and Co., Cockeysville, MD, USA). Production of ESBLs was detected with the use of two disc diffusion methods: the double-disc synergy test (DDST) according to Jarlier et al. and the diagnostic disc (DD) test according to Appleton. ESBLs were produced by 5,3% strains of Bacteroides spp. For all Bacteroides spp. strains MIC values were determined by gradient diffusion method Etest (AB BIODISK, Sweden). ESBLs and MIC were performed on Wilkins-Chalgren solid medium supplemented with 5% sheep blood (Difco Lab., USA) and all plates were incubated at 35 degrees C for 48 hours in 85% N2, 10% H2, 5% CO2. Most Gram-negative obligate anaerobes isolated from clinical specimens are still susceptible to imipenem (100%), metronidazole (99,3%) and beta-lactam antibiotics with beta-lactamase inhibitors: piperacillin/tazobactam (99,3%), ticarcillin/clavulanate (99.3%), amoxicillin/clavulanate (97.8%).