Antibiotic-associated colitis and cystic fibrosis.

The use of antibiotics in patients with cystic fibrosis is widespread, and fecal carriage of Clostridium difficile occurs in up to 50% of these patients; however, antibiotic-associated colitis appears to be a rare occurrence. The reasons why this is so remain unknown. A case of antibiotic-associated colitis occurring in a patient with cystic fibrosis is described. Possible mechanisms for the rarity of antibiotic-associated colitis are reviewed and implications for prompt diagnosis and therapy are discussed.