This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Renal Tubular And Obstructive Disorders, Subject name: Pediatrics
[{'content': 'The most common underlying anomaly in a child with recurrent urinary tract infection is: \nSelect and explain. \nA. Posterior urethral valves, B. Vesicoureteric reflux, C. Neurogenic bladder, D. Renal calculi', 'role': 'user'}, {'content': 'Answer: B \nExplanation: * 30-35% children with UTI have VUR Recurrent UTI are observed in 30-50% children, usually within 3 months of the first episode. Predisposing factors for recurrent UTI include female sex, age below 6 months, obstructive uropathy, severe vesicoureteric reflux (VUR), habitual postponement of voiding (voiding dysfunction), constipation and repeated catheterization, e.g. for neurogenic bladder.', 'role': 'assistant'}]