Renal papillary necrosis is defined as coagulative necrosis of the renal papilla. The renal medulla and papilla are susceptible to ischemic necrosis due to their blood supply and hypertonic environment.

Causes of renal papillary necrosis include diabetes mellitus, abuse of analgesics, non-steroidal anti-inflammatory drugs (NSAIDs), sickle cell anemia, pyelonephritis, renal vein thrombosis, tuberculosis, and obstructive uropathy.