Abstract: Objective · To analyze the clinical features, diagnosis and treatment of adult Merkel diverticulum (MD) with complications. Methods · The basic clinical data, 99mTcO4- ectopic gastric mucosal radionuclide imaging, abdominal CT and treatment methods of 39 patients with MD complications in the First Affiliated Hospital of Nanchang University 2009 to 2019 were analyzed retrospectively. The differences of age, gender and clinical characteristics among the patients with different complications were analyzed. Results · The incidence rate of male MD and female MD was 3.88:1; the symptoms were painless bloody stool, abdominal pain, nausea and vomiting, etc. The main complications were hemorrhage, diverticulitis and intestinal obstruction, accounting for 53.8%, 25.6% and 20.5%, respectively. The gender and age among the patients with complications of hemorrhage, diverticulitis and intestinal obstruction were not statistically different, while the distance between diverticulum and ileocecal was statistically significant among the three groups (P0.010). The distance between diverticulum and ileocecal in the hemorrhage group was farther than that in the intestinal obstruction group (P0.040). Nineteen patients underwent radionuclide imaging examination, the positive detection rate was 63.2% (12/19), and 12 cases were bleeding patients. Thirty-nine cases were examinedabdominal CT, and the overall detection rate was 15.4% (6/39). All the 10 patients were diverticulitis, in with the detection rate of CT examination was 60.0% (6/10). All patients underwent surgical resection. Conclusion · The incidence of MD complications in adults is low, mainly in males. The most common complication is hemorrhage, and the distance between diverticulum and ileocecal of hemorrhage patients is farther than that of intestinal obstructive patients. 99mTcO4- radionuclide imaging is important for the diagnosis of MD complicated with blood in the stool, and the abdominal CT has a high diagnostic value for diverticulitis. If necessary, combined examination can improve the detection rate. MD complications in adults can be treatedsurgery.

Key words: adult, Meckel diverticulum (MD), complication, diagnosis, treatment