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': 'Most common cause of hemolytic uremic syndrome is – \nSelect and explain. \nA. E.coli, B. Shigella, C. Salmonella, D. Psedonomis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Etiology of HUS\n\nHUS usually follows an episode of acute gastroenteritis.\nLess commonly, patient may present after an upper respiratory tract infection.\nThe organisms responsible are -\nE.coli (most common) → EHEC (shiga toxin producing) \xa0 \xa0 \xa0 \xa0 \xa0\xa0\nShigella dysenteriae\xa0\xa0\xa0\xa0\xa0\nSalmonella\xa0\xa0\xa0\xa0\xa0\nBartonella\xa0\xa0\xa0\nStreptococcus pneumonia\xa0\xa0\xa0\xa0\xa0\xa0\nCampylobacter', 'role': 'assistant'}]