This study analysed 330 Clostridium difficile strains isolated from patients with C. difficile infection who were hospitalized in two university hospitals (H1 and H2) in Warsaw, Poland, over the... Show moreThis study analysed 330 Clostridium difficile strains isolated from patients with C. difficile infection who were hospitalized in two university hospitals (H1 and H2) in Warsaw, Poland, over the period 2004-2006. Strains were investigated for the presence of tcdA (A), tcdB (B) and binary toxin (CDT) genes, and antimicrobial susceptibility was determined against nine agents. Among the 330 C. difficile isolates, 150 (45.4%) were classified as A(+)B(+)CDT(-), 18 (5.5%) as A(+)B(+)CDT(+), 144 (43.6 %) as A(-)B(+)CDT(-) and 18 (5.5 %) as A(-)B(-)CDT(-). The predominant PCR ribotype in hospitals H1 and H2 was type 017 and accounted for 48.3 and 40.0%, respectively. Only one PCR ribotype 027 strain was found. The rates of resistance to erythromycin and clindamycin in hospitals H1 and H2 were 53.6 and 53.6%, and 48.6 and 47.5%, respectively, whereas resistance rates to the newer fluoroquinolones gatifloxacin and moxifloxacin were 38.5 and 38.5% (H1) and 38.4 and 40.1% (H2). Erythromycin resistance was frequently associated with resistance to clindamycin and newer fluoroquinolones in strains belonging to type 017. No metronidazole- and vancomycin-resistant isolates were found, although two C. difficile isolates had elevated MIC values of metronidazole (MIC range 1.0-1.5 mg l(-1)) and 15 strains revealed elevated MIC values for vancomycin (MIC range 1.5-2.0 mg l(-1)). In conclusion, an increase in non-027 CDT-producing C. difficile strains was observed in Poland, but C. difficile PCR ribotype 017 remains a major circulating type. Show less
The coincidental increase in norovirus outbreaks and Clostridium difficile infection (CDI) raised the question of whether these events could be related, e.g. by enhancing spread by diarrhoeal... Show moreThe coincidental increase in norovirus outbreaks and Clostridium difficile infection (CDI) raised the question of whether these events could be related, e.g. by enhancing spread by diarrhoeal disease outbreaks. Therefore, we studied the prevalence of C. difficile in outbreaks of viral gastroenteritis in nursing homes for the elderly and characterised enzyme immunoassay (EIA)-positive stool samples. Stool samples from nursing home residents (n = 752) in 137 outbreaks of viral aetiology were investigated by EIA for the presence of C. difficile toxins. Positive samples were further tested by a cell neutralisation cytotoxicity test, a second EIA and culture. Cultured isolates were tested for the presence of toxin genes, the production of toxins and characterised by 16S rRNA polymerase chain reaction (PCR) and sequencing. Twenty-four samples (3.2%) tested positive in the EIA. Of these 24 positive samples, only two were positive by cytotoxicity and three by a second EIA. Bacterial culture of 21 available stool samples yielded a toxinogenic C. difficile PCR ribotype 001 in one patient sample only. In conclusion, we found no evidence in this retrospective study for an association between viral gastroenteritis outbreaks and C. difficile. The high rate of false-positive EIA samples emphasises the need for second confirmation tests to diagnose CDI. Show less
