Asymptomatic carriage of Clostridium difficile in patients with cystic fibrosis.

Faecal samples from 37 patients with cystic fibrosis and 40 control patients at the Brompton Hospital and the London Chest Hospital were examined for the presence of Clostridium difficile. The organism was isolated from 2 (17%) of control patients who were receiving antibiotics and from one (3.6%) of control patients who had no antimicrobial treatment. Thirty two per cent of the patients with cystic fibrosis excreted C difficile, though none of them had diarrhoea. Two of the three isolates from control patients and nine of the 12 isolates from patients with cystic fibrosis produced toxin B (cytotoxin) in vitro. Toxin B was present in the stools of one of the control patients and three of the patients with cystic fibrosis; toxin A (enterotoxin) was not detected in the faeces of the patients with cystic fibrosis. Two cytotoxigenic strains of C difficile isolated from patients with cystic fibrosis were examined in hamsters; both were virulent, and the animals died.