What is amyloidosis?

Amyloidosis is a disease in which amyloid proteins are deposited and build up in vital organs. This buildup of proteins causes these organs to thicken and lose function.

Our bodies make several proteins that can cause amyloidosis. In order to treat a patient who has amyloidosis, it is very important to know the exact protein that is causing the disease.

What is AA amyloidosis?

Serum amyloid A protein occurs at high levels when inflammation (irritation and swelling) is present in the body. AA amyloidosis occurs when Serum Protein A levels in the bloodstream remain high for a long period of time. This can be seen in chronic (long-term) inflammatory conditions such as rheumatoid arthritis, inflammatory bowel disease (Crohn’s disease, ulcerative colitis), and chronic infections. It is also seen in inherited periodic fever syndromes such as Familial Mediterranean Fever. Sometimes referred to as secondary amyloidosis due to the underlying inflammatory disease, AA amyloidosis is more common in developing countries. This form rarely significantly affects the heart.

What causes amyloidosis?

Amyloidosis is a “protein misfolding disorder.” Normally, proteins in the bloodstream are removed and/or recycled once they have completed their job. In amyloidosis, however, a protein can change shape (or “misfold”) and can no longer be cleared. These misfolded proteins clump together and form amyloid fibrils, which are then deposited in the spaces between the cells of vital organs. As amyloid fibrils build up in one or more tissues and organs, the cells can no longer work together and the organ(s) loses function.

Amyloid protein | Cleveland Clinic

What are the signs and symptoms of AA amyloidosis?

AA amyloidosis can affect many organs, resulting in the following signs and symptoms:

Signs and symptoms indicating the kidneys are affected include:

Signs indicating the liver is affected include:

  • Enlarged liver (hepatomegaly)

Symptoms indicating the stomach or intestines are affected include:

Symptoms indicating the heart is affected (uncommon) include:

  • Swelling of the feet or legs
  • Shortness of breath
  • Palpitations
  • Chest pain

Other signs and symptoms:

  • Enlarged spleen (splenomegaly)
  • Increased level of protein in the urine (proteinuria)
  • High cholesterol levels (hypercholesterolemia)

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