Endoscopic appearance is not sufficient for a diagnosis of segmental colitis associated with diverticulosis.

Background: It has been recently shown that the prevalence of segmental colitis associated with diverticulosis (SCAD) is about 2% of all patients who have colonic diverticulosis. However, sometimes it can be overdiagnosed if only endoscopic criteria are applied. We have recognized endoscopic signs of SCAD (lesions of the interdiverticular mucosa with diverticular and rectal sparing) in patients with a variety of conditions other than SCAD. Method: We reviewed clinical, endoscopic and histologic data from selected patients with endoscopically visualized signs of SCAD. Results: Five patients with endoscopic signs of SCAD were included in this study. SCAD was excluded by the lack of specific biopsy findings, combined with laboratory exams. Final diagnoses were iatrogenic colitis due to immunotherapy (n=1), eosinophilic colitis (n=1), Salmonella typhi (n=1), undetermined inflammatory bowel disease (n=1), and Crohn's disease (n=1). Conclusions: Lesions of the interdiverticular mucosa with diverticular and rectal sparing are not specific for SCAD, but rather a predictor of disease. In consequence, histology and, if necessary, laboratory analyses are mandatory to support a correct SCAD diagnosis.