Collagenous and lymphocytic colitis in Iceland.

The aim of this study was to determine the nationwide incidence of collagenous and lymphocytic colitis in Iceland and the location of histopathological changes in the large bowel. All pathology reports of patients diagnosed with or suspected of having collagenous colitis or lymphocytic colitis in the period 1995-1999 were identified. All pathology samples were reevaluated using strict diagnostic criteria.