Renal disease - atheroembolic

Alternative names

Atheroembolic renal disease; Cholesterol embolization syndrome; Atheroemboli - renal; Atherosclerotic disease - renal

Definition

Atheroembolic renal disease (AERD) refers to an inflammatory reaction in the small blood vessels of the kidneys. It occurs when cholesterol crystals from atherosclerotic plaques (lipid and cholesterol plaques in the walls of blood vessels) break off and move to the kidneys. It often results in irreversible damage to the kidney tissue. If severe enough, it may result in end stage renal disease.

Causes, incidence, and risk factors

AERD results from atherosclerotic plaque, the source of cholesterol crystals. A diseased, atherosclerotic aorta is the most common cause of AERD. The syndrome is most often begins following direct mechanical injury to the plaque, causing the release of the cholesterol crystals into the blood stream. Thus, cardiac catheterization is a common precipitating factor, as is direct trauma during aortic surgery.

Thrombolysis or anticoagulation (a process of making the blood thin so as to avoid clot formation in some disease states) have been known to agitate the plaques and release cholesterol crystals. Rarely, the syndrome may occur spontaneously.

Once in the circulation, the crystals lodge in small blood vessels. As the aorta is the most common source of the crystals, the kidney, intestine and legs are at prime risk.

Once in the tiny blood vessels called arterioles, the crystals cause an intense inflammatory response. The end result is organ damage due to decreased blood supply. In the kidneys, this may lead to acute renal failure if the reaction is severe.

A spectrum of responses may be seen, though. These range from serious end stage renal disease, requiring dialysis, to only mild elevation in plasma creatinine (a test used to gauge kidney function).

The risk factors for AERD are the same as risk factors for atherosclerosis. This is a syndrome seen predominantly in elderly males with vascular disease.

Symptoms

AERD may not have any symptoms. However, it can cause the following:

• Foot pain, ulcers on the feet, or "blue toes" (due to decreased blood flow to the feet and toes)
  
• Pain in the abdomen, nausea or vomiting (due to decreased blood flow to the intestine)
  
• Pancreatitis (inflammation of the pancreas) or hepatitis (inflammation of the liver), although these are rare
  
• Strokes or blindness
  
• Flank pain and blood in the urine (rare)