Necrosis - renal papillae

Alternative names

Renal papillary necrosis; Renal medullary necrosis

Definition

Renal papillary necrosis is a disorder of the kidneys involving death of some or all of the renal papillae.

Causes, incidence, and risk factors

The renal papillae are the areas of the kidney where the openings from the collecting ducts enter the renal pelvis. Necrosis (tissue death) of this area may result in impairment of the kidneys ability to concentrate the urine with ensuing polyuria (increased urine volume, usually in excess of 3 liters per day) and nocturia (frequent urination at night).

The necrotic tissue may be sloughed off, and it may be present in the urine as tissue, or the tissue may obstruct the renal pelvis or the ureter. Presence of necrotic tissue in the urine increases the risk of Urinary tract infections. Necrosis of multiple papillae in the kidney can lead to eventual failure of that kidney.

Renal papillary necrosis is most commonly associated with analgesic nephropathy, diabetic nephropathy, renal transplant rejection, urinary tract obstruction, kidney infections and sickle cell anemia. Sickle cell anemia is a common cause of renal papillary necrosis in children.

Symptoms

• Tissue in the urine
  
• Cloudy urine
  
• Dark, rust-colored, or brown urine
  
• Bloody urine
  
• Back pain or flank pain
  o May be on only one side
  o May be acute
  o May be colicky or spasm-like pain
  

Additional symptoms that may be associated with this disease:

• Painful urination
  
• Urinary hesitancy
  
• Increased Urinary frequency or urgency
  
• Polyuria (large urine volumes)
  
• Nocturia (urinating frequently at night)
  
• Incontinence
  
• Chills
  

Signs and tests
An examination may reveal tenderness on palpation over the affected kidney. There may be a history of chronic or . There may be signs of obstructive uropathy or renal failure.