Acute inflammation of the GALLBLADDER wall. It is characterized by the presence of ABDOMINAL PAIN; FEVER; and LEUKOCYTOSIS. Gallstone obstruction of the CYSTIC DUCT is present in approximately 90% of the cases. The disease is Cholecystitis, Acute (EFO_1001289, an Experimental Factor Ontology identifier). Also known as: acute cholecystitis.