necrosis of the renal papillae, caused by the following
Ischemia:
severe dehydration,
shock
vasculitis
sickle cell disease:
due to the vaso-occlusive events
diabetes
as a result of microvascular and macrovascular changes
Infections:
Chronic or severe urinary tract infections
Obstruction
Analgesic Nephropathy:
Chronic use of certain analgesic medications, especially nonsteroidal anti-inflammatory drugs (NSAIDs) and aspirin, has been associated with renal papillary necrosis. These drugs can compromise renal blood flow and contribute to tissue damage.