The main causes of acute cholecystitis are obstruction of the gallbladder duct and bacterial infection. 1. Obstruction of the gallbladder duct: when the bile duct stone moves to the periphery of the gallbladder duct, it can be embedded in the neck of the gallbladder or block the gallbladder duct. The embedded stone can cause direct damage to the mucous membrane, causing obstruction of bile discharge, bile retention and concentration. The high concentration of bile acids can cause cell damage, aggravate inflammation, cause edema and even necrosis. 2. Bacterial infection: the main pathogenic bacteria are Escherichia coli, Klebsiella, Enterococcus faecalis, etc. Some patients can also be combined with anaerobic infection. The pathogenic bacteria can enter the gallbladder wall retrograde from the bile duct, and can also enter through the blood circulation or lymph node route. Acute cholecystitis is recommended to seek timely medical treatment, under the guidance of the doctor standardized diagnosis and treatment.