The document discusses cholecystitis, which is inflammation of the gallbladder. It is usually caused when a gallstone gets stuck in the gallbladder duct. There are four types: calculous (caused by gallstones), acalculous, acute, and chronic. Symptoms include pain, fever, nausea. Diagnosis involves ultrasound, CT, blood tests. Treatment options are supportive care, antibiotics, pain medication, and often cholecystectomy to remove the gallbladder. Complications can include infection if not treated.