Primary Amyloidosis

Amyloid (pronounced am'-i-loyd) is an abnormal protein that may be deposited in the body's tissues or organs. Most often this abnormal protein comes from cells in the bone marrow. Amyloidosis (pronounced am-i-loy-do'-sis) results when enough amyloid protein builds up in one or more organs to cause the organ to malfunction. The heart, kidneys, nervous system and gastrointestinal tract are most often affected.

While amyloidosis has many types , the most common is a disease of the bone marrow called primary systemic amyloidosis. Bone marrow makes antibodies that protect against infection and disease. After performing their function, these antibodies are broken down and recycled by the body. In amyloidosis, cells in the bone marrow produce antibodies that cannot be broken down or recycled. These antibodies build up in the bloodstream. Ultimately, they leave the bloodstream and can deposit in tissues as amyloid. The disease can cause various symptoms depending on the organ affected.

Primary systemic amyloidosis is rare, affecting about eight persons per million annually. Its cause is unknown. It can affect anyone, but the majority of people who develop amyloidosis are over 40 years old, with 63 being the average age at diagnosis. Two-thirds of patients with primary amyloidosis are men. Amyloidosis may be disabling or life threatening.

Primary amyloidosis is not contagious or inherited. About 10 percent of patients who have multiple myeloma (a form of bone marrow cancer) develop amyloidosis. Although amyloid is an abnormal protein, diet and the amount of protein eaten play no role in the development of the disease. Also, there is no recognized link between amyloidosis and stress or occupation