This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pediatrics
[{'content': 'A 6-month-old baby with H/O bloody diarrhoea of 2 days duration with abdominal distension and on examination the baby screams, diagnosis is – \nSelect and explain. \nA. Intussuscetion, B. HUS, C. Appendicitis, D. Ac. Enterocolitis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Clinical features of intussusception\n\nSudden onset\nSevere paroxysmal colicky pain that recurs at frequent intervals.\nPain is accompanied by straining efforts with legs and knees flexed and loud cries (screaming).\nLethargy\nBlood and mucus produce a current jelly stool.\nReflex vomiting is an early sign.\nIn later stages, vomiting becomes bile stained.\nAbdominal distension and tenderness develop as intestinal obstruction becomes more acute.\nTender sausage - shaped palpable mass in the right upper abdomen with its long axis cephalocaudal.\nOccasionally intestine prolapses through the rectum.', 'role': 'assistant'}]