Characterized by coagulative necrosis of the renal medullary pyramids and papillae as a sequela of ischemic and toxic processes on the kidney. In general, occurs in older individuals, typically those older than 60 years, with the exception of pediatric patients with sickle cell disease or hypoxemia.

Conditions that predispose to the development of renal papillary necrosis include pyelonephritis, urinary tract obstruction, sickle cell hemoglobanopathies including sickle cell trait, tuberculosis (TB), liver cirrhosis, overuse of analgesic agents (especially NSAIDs), renal transplant rejection, radiation to the kidney, type 2 diabetes mellitus, and systemic vasculitis. In many cases, patients who develop renal papillary necrosis have more than 2 of these risk factors.

Presentation is variable, ranging from acute progressive papillary necrosis characterized by the acute onset of symptoms with fever, chills, flank pain with oliguria, and possible progression to renal failure to chronic papillary necrosis leading to progressive renal insufficiency. Patients present with an inability to concentrate their urine. Obstructive symptoms of flank pain and colic may develop due to sloughed papillary cells, and pyelonephritis may develop in necrotic areas of renal papillae.