CHOLESTEROL EMBOLISM

The symptoms experienced in cholesterol embolism depend largely on the organ involved. Some of the symptoms are:

• Fever, muscle ache and weight loss.
• Embolism to the legs causes a mottled appearance and purple discoloration of the toes, small infarcts and areas of gangrene due to tissue death that usually appear black, and areas of the skin that assume a marbled pattern known as livedo reticularis. The pain is usually severe and requires opiates.
• Kidney involvement leads to the symptoms of renal failure, which are non-specific but usually cause nausea, reduced appetite (anorexia), raised blood pressure (hypertension), and occasionally the various symptoms of electrolyte disturbance such as an irregular heartbeat.
• Hematuria (bloody urine) are reported to some patients but this may only be detectable on microscopic examination of the urine. Increased amounts of protein in the urine may cause edema (swelling) of the skin (a combination of symptoms known as nephrotic syndrome).[3]
• Digestive tract. Symptoms that emboli have spread to it are: reduced appetite, nausea and vomiting may occur, as well as nonspecific abdominal pain, gastrointestinal hemorrhage (vomiting blood, or admixture of blood in the stool), and occasionally acute pancreatitis (inflammation of the pancreas).[3]
• Both the central nervous system (brain and spinal cord) and the peripheral nervous system may be involved. Emboli to the brain may cause stroke-like episodes, headache and episodes of loss of vision in one eye (known as amaurosis fugax.

DIAGNOSIS

Differential diagnosis

Findings on general investigations (such as blood tests) are not specific for cholesterol embolism, which makes diagnosis difficult. The main problem is the distinction between cholesterol embolism and vasculitis (inflammation of the small blood vessels), which may cause very similar symptoms – especially the skin findings and the kidney dysfunction.

Blood and urine

• Tests for inflammation (C-reactive protein and the erythrocyte sedimentation rate) are typically elevated, and abnormal liver enzymes may be seen.
• If the kidneys are involved, tests of renal function (such as urea and creatinine) are elevated.
• The complete blood count may show particularly high numbers of a type of white blood cell known as eosinophils (more than 0.5 billion per liter); this occurs in only 60-80% of cases, so normal eosinophil counts do not rule out the diagnosis.
• Examination of the urine may show red blood cells (occasionally in casts as seen under the microscope) and increased levels of protein; in a third of the cases with kidney involvement, eosinophils can also be detected in the urine.
• If vasculitis is suspected, complement levels may be determined as reduced levels are often encountered in vasculitis; complement is a group of proteins that forms part of the innate immune system. Complement levels are frequently reduced in cholesterol embolism, limiting the use of this test in the distinction between vasculitis and cholesterol embolism.

Tissue diagnosis

The microscopic examination of tissue (histology) gives the definitive diagnosis. The diagnostic histopathologic finding is intravascular cholesterol crystals, which are seen as cholesterol clefts in routinely processed tissue (embedded in paraffin wax).The cholesterol crystals may be associated with macrophages, including giant cells, and eosinophils.

TREATMENT

Treatment of an episode of cholesterol emboli is generally symptomatic. That means it deals with the symptoms and complications but cannot reverse the phenomenon itself.In kidney failure resulting from cholesterol crystal emboli, statins (medication that reduces cholesterol levels) have been shown to halve the risk of requiring hemodialysis.