This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urology, Subject name: Surgery
Obstructive causes of acute renal failure are all Except 
Select and explain. 
A. Bilharzia, B. Duplex ureter, C. Retroperitoneal fibrosis, D. Renal calculi
B: Duplex ureter
Answer: B: Duplex ureter 
Explanation: Obstructive causes of acute renal failure include:* calculi;* pelvic malignancy;* surgery;* retroperitoneal fibrosis;* bilharzia;* crystalluria.Bailey and love 26e pg: 1284