What causes Acute cholecystitis?
In 90% of cases, acute cholecystitis is caused by gallstones in the gallbladder. Other causes include severe illness and (rarely) tumors of the gallbladder. Acute cholecystitis occurs when bile becomes trapped in the gallbladder. The buildup of bile causes irritation and pressure in the gallbladder. This can lead to infection and a hole (perforation) in the organ. </s>