Pseudomembranous colitis

Alternative names:

antibiotic associated colitis; colitis - pseudomembranous; necrotizing colitis

Definition:

A severe condition of the colon that results in death of local tissue (necrosis), occurring as a complication of antibiotic therapy.

Causes, incidence, and risk factors:

Nearly all antibiotics can cause this condition. Clostridium difficile, which occurs normally in the intestine in 10% of the population, overgrows in the presence of antibiotics. The bacteria releases a powerful toxin that is responsible for the symptoms. The lining (mucosa) of the colon becomes denuded and hemorrhagic. Risk factors are antibiotic usage and history of previous pseudomembranous colitis. The incidence is 1 out of 1,000 people.

Ampicillin is the most common antibiotic associated with this disease in children. Pseudomembranous colitis is rare in infants less than 12 months old because of the presence of protective maternal antibodies.