Amyloid Light-chain (AL) amyloidosis, primary systemic amyloidosis (PSA) or just primary amyloidosis is the most common form of systemic amyloidosis in the US. The disease is caused when a person's antibody-producing cells do not function properly and produce abnormal protein fibers made of components of antibodies called light chains. These light chains come together to form amyloid deposits in different organs which can cause serious damage to these organs. Abnormal light chains in blood and urine are sometimes referred to as "Bence Jones protein".
Signs and symptoms
AL amyloidosis can affect a wide range of organs, and consequently present with a range of symptoms. The kidneys are the most commonly affected organ in AL amyloidosis. Symptoms of kidney disease and renal failure can include fluid retention, swelling, and shortness of breath.
In addition to kidneys, AL amyloidosis may affect the heart, peripheral nervous system, gastrointestinal tract, blood, lungs and skin. Heart complications, which affect more than a third of AL patients, include heart failure and irregular heart beat. Other symptoms can include stroke, gastrointestinal disorders, enlarged liver, diminished spleen function, diminished function of the adrenal and other endocrine glands, skin color change or growths, lung problems, bleeding and bruising problems, fatigue and weight loss.
AL amyloidosis can occur spontaneously, however, it is often associated with other blood disorders, such as multiple myeloma and Waldenström's macroglobulinemia. About 10% to 15% of patients with multiple myeloma may develop overt AL amyloidosis.
Both blood and the urine can be tested for the light chains, which may form amyloid deposits, causing disease. However, the diagnosis requires a sample of an affected organ.
The most effective treatment is autologous bone marrow transplants with stem cell rescues. However many patients are too weak to tolerate this approach.
Other treatments can involve application of chemotherapy similar to that used in multiple myeloma. A combination of bortezomib and dexamethasone has been proposed, as has melphalan and dexamethasone.
Median survival for patients diagnosed with AL amyloidosis was 13 months in the early 1990s, but had improved to c. 40 months a decade later.
AL amyloidosis is a rare disease; only 1200 to 3200 new cases are reported each year in the United States. Two thirds of patients with AL amyloidosis are male and less than 5% of patients are under 40 years of age.
- ↑ Gertz MA (June 2004). "The classification and typing of amyloid deposits". Am. J. Clin. Pathol. 121 (6): 787–9. PMID 15198347. doi:10.1309/TR4L-GLVR-JKAM-V5QT.
- ↑ "Amyloidosis Causes, Diagnosis, Symptoms, and Treatment on MedicineNet.com".
- ↑ "Amyloidosis and Kidney Disease". National Institute of Diabetes and Digestive and Kidney Diseases. Retrieved 23 November 2011.
- ↑ 4.0 4.1 4.2 4.3 4.4 UNC Kindey Center. "AL Amyloidosis". UNC. Retrieved 22 November 2011.
- ↑ "Amyloidosis". University of Maryland Medical Center. Retrieved 23 November 2011.
- ↑ Madin, Sumit; Dispenzieri, Angela (2010). "Clinical Features and Treatment Response of Light Chain (AL) Amyloidosis Diagnosed in Patients With Previous Diagnosis of Multiple Myeloma" (PDF). Mayo Clinic Proceedings 83 (3): 232–238. doi:10.4065/mcp.2009.0547. Retrieved 22 November 2011.
- ↑ Sanchorawala, Vaishali (2006). "Light-Chain (AL) Amyloidosis: Diagnosis and Treatment". Clinical Journal of the American Society of Nephrology 1 (6): 1334–1341. doi:10.2215/cjn.02740806. Retrieved 1 December 2011.
- ↑ 8.0 8.1 Palladini G, Perfetti V, Obici L et al. (April 2004). "Association of melphalan and high-dose dexamethasone is effective and well tolerated in patients with AL (primary) amyloidosis who are ineligible for stem cell transplantation". Blood 103 (8): 2936–8. PMID 15070667. doi:10.1182/blood-2003-08-2788.
- ↑ 9.0 9.1 "BU: Amyloid Treatment & Research Program".
- ↑ Kastritis E, Anagnostopoulos A, Roussou M et al. (October 2007). "Treatment of light chain (AL) amyloidosis with the combination of bortezomib and dexamethasone". Haematologica 92 (10): 1351–8. PMID 18024372. doi:10.3324/haematol.11325.
- ↑ Ashutosh D. Wechalekar (2007). "Perspectives in treatment of AL amyloidosis". British Journal of Haematology 140 (4): 365–377. doi:10.1111/j.1365-2141.2007.06936.x. Retrieved 23 November 2011.
- ↑ "Primary AL". Amyloidosis Foundation. Retrieved 23 November 2011.