<prompt> Papillary necrosis is most commonly seen in-AI 91Diabetes MellitusSickle cell anemiaAcute pyelonephritisAnalgesic nephropathy  <response>: Renal papillary necrosis is a disorder of the kidneys in which all or part of the renal papillae die. The renal papillae are the areas where the openings of the collecting ducts enter the kidney and where urine flows into the ureters.CausesRenal papillary necrosis often occurs with analgesic nephropathy. This is damage to one or both kidneys caused by overexposure to pain medicines. But, other conditions can also cause renal papillary necrosis, including:Diabetic nephropathyKidney infection pyelonephritisKidney transplant rejectionSickle cell anemia, a common cause of renal papillary necrosis in childrenUrinary tract blockage This is a list of causes in order of incidence.A: analgesic abuse phenacetin, NSAIDs, paracetamol: especially in combinationD: diabetes mellitusS: sickle cell diseaseP: pyelonephritis especially in childrenO: obstructionR: renal vein thrombosisT: renal tuberculosis not usually confined to papillaeC: cirrhosis 