Linear mucosal defect may be characteristic of lansoprazole-associated collagenous colitis

BackgroundAlthough some cases of collagenous colitis have been induced by lansoprazole (LPZ), the clinicopathologic features of LPZ-associated collagenous colitis have not been elucidated.ObjectiveTo elucidate the clinical, endoscopic, and histopathologic features of LPZ-associated collagenous colitis.DesignRetrospective case study.PatientsThe subjects were 13 patients with collagenous colitis diagnosed during a period from 2002 to 2007.Main Outcome MeasurementsThe colonoscopic and histopathologic findings were compared retrospectively between 9 cases of LPZ use (LPZ group) and 4 cases without the use of LPZ (non-LPZ group).ResultsA colonoscopy revealed a linear mucosal defect more frequently in the LPZ group (7 of 9 cases [78%]) than in the non-LPZ group (0 of 4 cases [0%], P = .02). Friable mucosa was also noted in 4 patients (44%) in the LPZ group but none in the non-LPZ group. The colonoscopic finding in the non-LPZ group was either normal mucosa or nonspecific minimal abnormalities, whereas patients in the LPZ group had either a linear mucosal defect, mucosal bleeding, or both (P = .001). On histologic examination, the subepithelial collagen band was thicker in patients in the LPZ group than in those in the non-LPZ group (median 45 vs 26.3 μm). All patients in the LPZ group recovered from diarrhea after discontinuance of LPZ.LimitationA small number of patients.ConclusionsLinear mucosal defects and friable mucosa may be characteristic colonoscopic findings in cases of LPZ-associated collagenous colitis.