This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Kidney disorders, Subject name: Pathology
Which of the following is the least likely cause of necrotizing papillitis of kidney? 
Select and explain. 
A. Sickle cell disease, B. Tuberculous pyelonephritis, C. Diabetes mellitus, D. Analgesic nephropathy
B: Tuberculous pyelonephritis
Answer: B: Tuberculous pyelonephritis 
Explanation: Necrotizing papillitis/ Renal papillary necrosis. When infection of renal pyramids develop in association with vascular diseases of the kidney or with urinary tract obstruction. DM is the commonest cause TB is the rarest cause of papillary necrosis. Acute papillary necrosis: Diabetes mellitus Sickle cell disease Chronic alcoholism Vascular disease Analgesic abuse nephropathy