This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urinary tract, Subject name: Pathology
Papillary necrosis is seen in all except 
Select and explain. 
A. NSAID's, B. DM, C. Sickle cell anemia, D. Shock
D: Shock
Answer: D: Shock 
Explanation: Causes of papillary necrosis*Diabetes mellitus*Sickle cell disease/trait*Analgesics*Urinary tract obstruction *Renal tuberculosis ( Ref: Robbins 8/e p934)