Detection of binary-toxin genes (cdtA and cdtB) among Clostridium difficile strains isolated from patients with C. difficile-associated diarrhoea (CDAD) in Poland

Clostridium difficile A+ B+ and A- B+ strains isolated from stool samples of patients with C. difficile-associated diarrhoea (CDAD) were selected from the University Hospital Warsaw collection. The binary-toxin genes cdtA and cdtB were detected by PCR in five of the 41 A+ B+ strains tested, but in none of the 17 A- B+ strains tested, giving 8.6 % prevalence (5/58) of binary-toxin-positive strains. All of the strains that were positive for binary-toxin genes were grouped into toxinotype IV, suggesting that in this institution toxinotype IV might dominate among the population of C. difficile with binary-toxin genes.