Collagenous colitis: a case report and review of the literature.

A case of collagenous colitis is reported and the literature reviewed. The disease presents with watery diarrhea and abdominal pain in middle-aged subjects. Women predominate in the small number of reported cases. Colonic and rectal biopsies show excessive collagenization of the so-called collagen table in the superficial lamina propria. There is an associated degeneration and desquamation of the interglandular epithelial lining cells. The cause is not known but the clinical course with symptomatic treatment can wax and wane with corresponding deterioration or improvement in the biopsy features.