Surgical treatment of acute abdomen during the SARS-CoV-2 pandemic was accompanied by an extremely high mortality rate, however, only a few studies have presented the results of acute inflammatory complications of diverticular disease (AICDD).AIM: analysis of treatment of AICDD in a COVID-19 hospital.PATIENTS AND METHODS: the retrospective study included 78 patients with acute diverticulitis (AD) from a COVID hospital, confirmed by CT or intraoperative revision. Assessment of COVID pneumonia, comorbidities, organ dysfunction, CT findings, peritonitis, treatment methods, and in-hospital mortality among patients was performed.RESULTS: organ dysfunction of ≥ 1 point on the qSOFA scale was detected in 59.0% of the patients. According to CT data, abdominal distant gas was detected in 48 (61.5%) patients, and pericolic gas in 14 (17.9%) patients. Segmental colon resection was performed in 60 (76.9%) patients, laparoscopic lavage (LL) of the abdominal cavity — in 3, non-operative treatment (NOT) with drainage of fluid collections — in 6, and only NOT in 10 patients. Most patients with distant or pericolic gas were operated on within an average time of 1 [0; 3.5] hours after admission. Diffuse peritonitis was detected during surgery in 45 (75%) of them. After resection, organ dysfunction of ≥ 2 points on the SOFA scale developed or progressed in 52 (86.7%) patients. The overall mortality rate was 48.7%, and the postoperative mortality was 63.3%. All patients (n = 38) died after segmental colon resection. Successful NOT was achieved in 4 patients with pericolic gas and 3 patients with distant gas.CONCLUSION: surgery for AICDD in patients with COVID-19 is associated with extremely high mortality, therefore, in the absence of obvious signs of diffuse peritonitis, initial non-operative treatment may be life-saving.