Amyloidosis is a metabolic storage disease that results from deposition of insoluble proteins, called amyloid proteins, in a wide variety of tissues. The disease may affect only one organ or multiple organs and tissues. Secondary amyloidosis, also known as amyloid A amyloidosis, is considered an acquired form of the disease that occurs in association with a wide variety of other diseases, most commonly chronic infections, cancers and other chronic inflammatory conditions.
Chronic Infections
Worldwide, chronic infections such as malaria and tuberculosis remain the most common diseases precipitating secondary amyloidosis. According to MayoClinic.com, osteomyelitis, an infection of the bone, may also be a trigger for secondary amyloidosis. The chronic inflammation caused by these infections stimulates the synthesis in the liver of amyloid A protein, which can subsequently deposit in tissues and organs.
Cancers
Malignancies, namely Hodgkin's lymphoma, gastrointestinal cancer, lung cancer and genitourinary carcinomas, can also trigger secondary amyloidosis. Multiple myeloma may also be associated with secondary amyloidosis, reports MayoClinic.com. The form of amyloidosis more commonly associated with multiple myeloma, however, is a different form of amyloidosis, known as amyloid L amyloidosis. Symptoms of amyloidosis related to cancer or other nonmalignant conditions are generally slow to develop and generally nonspecific. Symptoms depend on the distribution and the amount of amyloid protein deposited. A diagnosis is usually not made until after significant organ damage has already occurred. No cure exists for amyloidosis, and treatment of secondary amyloidosis generally involves addressing the underlying cause.
Chronic Inflammatory Conditions
Other causes of chronic inflammation, such as rheumatoid arthritis or ankylosing spondylitis, have also been associated with systemic amyloidosis. An inherited chronic inflammatory condition, known as familial Mediterranean fever, has also been linked to amyloidosis. Familial Mediterranean fever is a rare intestinal disease that primarily affects people of Mediterranean origin. Symptoms are usually present by the age of 20. Patients diagnosed with secondary amyloidosis have usually had a related inflammatory disorder for at least 10 years.
References
- Mayoclinic.com: Amyloidosis
- "Harrison's Principles of Internal Medicine [CD-ROM] 15th edition"; Eugene Braunwald, M.D.; 2001
- "Clinics in Liver Disease"; Metabolic Storage Diseases: Amyloidosis; E.M. Brunt and D.G. Tinaikos; 2004
- "Dimensions of Critical Care Nursing"; Recognition and Treatment of Amyloidosis; Nancy McGowan; 2006
- "Hepatogastroenterology"; Secondary Amyloidosis Due to FMF; O. Yonem and Y. Bayraktar; 2007
