Definition of Primary amyloidosis:

Primary amyloidosis is a disorder in which abnormal proteins build up in tissues and organs. Clumps of the abnormal proteins are called amyloid deposits.

Causes, incidence, and risk factors:

The cause of primary amyloidosis is unknown. The condition is related to abnormal and excess production of antibodies by a type of immune cell called plasma cells.

Primary amyloidosis can lead to conditions that include:

• Carpal tunnel syndrome
• Heart muscle damage (cardiomyopathy) leading to congestive heart failure
• Intestinal malabsorption
• Liver enlargement
• Kidney failure
• Nephrotic syndrome
• Neuropathy (nerves that do not work properly)
• Orthostatic hypotension (abnormal drop in blood pressure with standing)

The deposits build up in the affected organs, causing them to become stiff, which decreases their ability to function.

Risk factors have not been identified. Primary amyloidosis is rare. It is similar to multiple myeloma, and is treated the same way.