Background/AimsDuodenitis is not infrequent finding in patient undergoing endoscopy. However, hospitalized patients have a higher incidence of secondary duodenal mucosal lesions that might be related with inflammatory bowel disease (IBD), cytomegalovirus (CMV) infection, tuberculosis, immunologic disorders, or other rare infections. We aimed to identify clinicopathologic features of duodenal mucosal lesions in hospitalized patients.MethodsAll hospitalized patients having duodenal mucosal lesions were identified by endoscopic registration data and pathologic data query from 2011 to 2014. The diagnostic index was designed to be sensitive; however, a detailed review of medical record and endoscopic findings was undertaken to improve specificity. Secondary duodenal lesion was defined as having specific reason to explain the duodenal lesion.ResultsAmong 6,334 hospitalized patients have undergone upper endoscopy, endoscopic duodenal mucosal lesions was detected in 475 patients. Secondary duodenal lesions was 21 patients (4.4%) and the most frequent secondary cause was IBD (n = 7). The mean age of secondary group was significantly lower than that in primary group (42.3 ± 18.9 years vs. 58.5 ± 16.8 years, p = 0.00), and nonsteroidal anti-inflammatory drugs were less frequently used in secondary group, but there was no differences of gender or presence of Helicobacter pylori. The involvement of distal part of duodenum including postbulbitis or panduodenitis was more frequently detected in secondary group than in primary group. By multivariate regression analysis, younger age of 29 years and the disease extent were significant predictors for the secondary mucosal lesions.ConclusionsSecondary duodenal mucosal lesions with different pathophysiology, such as IBD or CMV infection, are rare. Disease extent and age seems the most distinctive feature of secondary duodenal mucosal lesions.