Collagenous colitis: a long-term follow-up study.
Collagenous colitis was first described in 1976. It is a rare disorder and the long-term course and prognosis of the disease are unknown. The aim of this study was to evaluate the course of the disease more than 5 years after the diagnosis. A retrospective follow-up of patients with collagenous colitis diagnosed during the period 1979-1990. All examinations performed at the time of diagnosis were reviewed and the clinical courses of the patients were determined by evaluation of the medical records. At a follow-up visit in 1996 complete histories were obtained and conventional laboratory tests were performed. Two men and 22 women aged 20-82 years with collagenous colitis were identified. At the time of diagnosis, extensive investigation did not reveal other gastrointestinal diseases. At the time of follow-up, six patients had died from diseases unrelated to collagenous colitis, 10 patients suffered from chronic or intermittent diarrhoea, and four patients had been without gastrointestinal symptoms for the last 2-10 years. None of the patients developed colorectal cancer or chronic inflammatory bowel disease. Four patients were lost to follow-up. Collagenous colitis is a benign disease, most often with a chronic course. No association with other gastrointestinal diseases was found.