This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Anatomy
[{'content': 'All are true about acute acalculous cholecystitis except \nSelect and explain. \nA. Distended GB, B. Vascular cause, C. Seen in bed ridden patients, D. Rapid course', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Distended GB is seen in scintigraphy Cholescintigraphy demonstrates absent gallbladder filling in acalculous cholecystitis Acalculous cholecystitis Acute inflammation of gallbladder without stones Clinical features Similar to acute calculous cholecystitis Patients may present with only unexplained fever, leucocytosis and hyperamylasemia and RUQ tenderness If untreated, rapid progression to gangrene and perforation may occur Ref: Sabiston 20th edition Pgno : 1508', 'role': 'assistant'}]