What is amyloidosis? Amyloidosis includes a group of disorders characterized by the deposition of abnormal protein aggregates in one or more tissues and organs. The name amyloidosis was coined more than 100 years ago, but it is only in the last 20 years that the composition and structure of amyloid proteins have been understood. Although amyloidosis is not equivalent to a tumor, it is serious and can even be life-threatening. There is a growing understanding of amyloidosis, and scientists are constantly conducting new research and exploring new treatments. There are three main types of amyloidosis Primary amyloidosis
is a disorder of bone marrow plasma cells that usually requires chemotherapy. It is the most common type of amyloidosis, accounting for 70% of all amyloidosis, with an estimated 2,000 new cases diagnosed each year in the U.S. The incidence in China is unknown and is estimated to be much higher than in the U.S. Multiple myeloma is occasionally associated with amyloidosis. Amyloid material consists of immunoglobulin light chains and can be deposited in any tissue and organ of the body. When amyloid accumulates to a certain level it causes organ dysfunction, with the kidneys, heart, nervous system and gastrointestinal tract being the most commonly affected organs. Under normal conditions, plasma cells produce protective antibodies in the bone marrow, which protect the body against germ infections and disease. Once these antibodies have completed their mission they are broken down and reused. When amyloidosis occurs, these antibodies cannot be broken down but accumulate in the blood and eventually leave the bloodstream to be deposited in tissues or organs in the form of amyloid. 2. Secondary amyloidosis
It is caused by chronic infections or inflammatory diseases, such as rheumatoid arthritis, familial Mediterranean fever, osteomyelitis or granulomatous ileitis. The amyloid deposits are called AA proteins. The progression of the disease can be slowed or stopped by medication and surgery to treat chronic infections or inflammatory diseases. 3. Hereditary amyloidosis
It is the only amyloidosis that is inherited. It is rare but seen in families of almost every race. The most common amyloid deposit is the transthyretin protein, which is synthesized in the liver. The transthyretin protein that causes amyloidosis is mutated. 4. Other types of amyloidosis
These include restrictive amyloidosis, β2 microglobulin amyloidosis, and Alzheimer’s disease. Restricted amyloidosis is associated with hormonal proteins, aging, and involves specific areas of the body without systemic lesions. β2 microglobulin amyloidosis occurs in patients on long-term dialysis. In Alzheimer’s disease, the amyloid protein deposited in the brain is called beta amyloid.