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Johns Hopkins Symptoms and Remedies

Johns Hopkins Medicine

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Amyloidosis

What is it?

Amyloidosis is a rare disorder resulting from the buildup of a waxy substance known as amyloid in various organs. The substance is comprised of certain types of protein that, when present in excess amounts in the bloodstream, may seep out into the tissues and solidify. The most common sites for amyloid deposition are the kidneys, heart, skin, gastrointestinal tract, and nervous system. Interference with function of the involved organs, symptoms, and prognosis depend upon the location and the amount of accumulated amyloid protein. In most cases, however, outlook is poor. Kidney failure, congestive heart failure, cardiac arrhythmias, and gastrointestinal bleeding are the major life-threatening complications of amyloidosis.

What Causes It?

  • In most cases, amyloidosis is caused by an abnormal protein (beta-amyloid), which is similar to the antibodies normally found in the blood; this condition is known as primary amyloidosis.
  • Secondary amyloidosis, which is much more rare, may occur as a complication of certain long-standing inflammatory or infectious diseases, including rheumatoid arthritis and tuberculosis. Again, the culprit is an abnormal protein in the blood that is deposited in the tissues.
  • Some forms of amyloidosis, affecting primarily the nerves, are inherited.
  • Long-term hemodialysis therapy may lead to amyloidosis.
  • Alzheimer's disease is thought to be related to a certain form of amyloidosis.
  • Amyloidosis of the heart may develop as a result of old age.

Prevention

  • There are no known ways to prevent most forms of amyloidosis.
  • Effective treatment of conditions such as tuberculosis or rheumatoid arthritis can prevent chronic inflammation that causes secondary amyloidosis.

Diagnosis

  • Patient history and physical examination are needed.
  • Protein levels in the blood and urine are measured.
  • Needle biopsy (removal of a tissue sample for microscopic examination) of abdominal fat is usually performed. Sometimes it is necessary to biopsy the kidney, rectum, or other parts of the body.

How to Treat It

  • For primary amyloidosis, chemotherapeutic drugs are often given.
  • The underlying disorder is treated in secondary amyloidosis.
  • Colchicine may be of benefit in treating both primary and secondary amyloidosis.
  • Medications may be given to treat the organs affected by amyloidosis.
  • Dialysis or kidney transplantation may be needed for patients with renal failure.

When to Call a Doctor

  • Amyloidosis can manifest itself in a myriad of ways. See a doctor if you develop unexplained weight loss, severe fatigue, or other symptoms of amyloidosis.