Purpose: comparative assessment of clinical manifestations of the course of destructive calculous cholecystitis before surgical operation. Methods. The study involved 86 patients with destructive cholecystitis (55 women and 31 men). 18 patients with destructive cholecystitis made up group 1, and 14 healthy people formed the control group. Patients with cholecystitis underwent cholecystectomy. The age groups were as following: 18-25, 26-40, 41-60 and 61-75 years. Grouping patients by age and sex enabled to reveal related concomitant diseases and complications of cholecystitis. 48 patients underwent open cholecystectomy, and 38 had laparoscopic cholecystectomy. The study determined the quantitative parameters of various enzymes in blood samples from patients with destructive cholecystitis, and the control group. Results. Standard open cholecystectomy was performed on in 55.8% of cases; consequently, laparoscopic cholecystectomy was performed in 44.2% of cases. A retrospective analysis of the surgical interventions performed has demonstrated 54 (62.8% ) patients had gallstones as a leading cause in the development of cholecystitis; 15 (17.4%) patients had phlegmon, 11 (12.8%) patients had gangrene, 4 (4.7%) patients had polyps, and 2 (2.3%) had gallbladder hypertrophy and complete closure of the lumen. 18 patients who underwent cholecystectomy, had developed various preoperative complications: 13 of them had local peritonitis, 2 patients had partial intestinal obstruction, and 3 were diagnosed as having mechanical jaundice. Local peritonitis was found out as the most common preoperative complication. 16 people had various comorbidities and made 18.6% of all patients. 8 (9.3%) out of 16 of the patients had diagnosis of diabetes mellitus. Conclusion. It should be noted that among all patients who underwent cholecystectomy, various preoperative complications were diagnosed, but local peritonitis was the commonest one. Diabetes mellitus against the background of impaired motility or tone of the intestines, bile ducts and the gallbladder leads to cholestasis and gallbladder inflammation.