Amyloidosis and Kidney Disease: NIDDK
Article title: Amyloidosis and Kidney Disease: NIDDK
Conditions: Kidney Disease, amyloidosis, primary amyloidosis, Dialysis-Related Amyloidosis, kidney disease, kidney dialysis
NIDDK Home : Health Information : Kidney Diseases : Kidney Failure
IntroductionProteins are important building blocks for all body parts, including muscles, bones, hair, and nails. Proteins circulate throughout the body in the blood and are normally harmless. Occasionally, cells produce abnormal proteins that can settle in body tissue, forming deposits and causing disease. When these deposits of abnormal proteins were first discovered, they were called amyloid, and the disease process amyloidosis.
In recent years, researchers have discovered that different kinds of proteins can form amyloid deposits and have identified several types of amyloidosis. Two of these types are closely related to kidney disease. In primary amyloidosis, abnormal protein production occurs as a first step and can lead to kidney disease. Dialysis-related amyloidosis (DRA), on the other hand, is a result of kidney disease.
One common sign of amyloidosis is the presence of abnormally high amounts of protein in the urine, a condition known as proteinuria. Healthy kidneys prevent protein from entering the urine, so the presence of protein may be a sign that the kidneys aren't working properly. A physician who finds large amounts of protein in the urine may also perform a biopsy--take a small sample of tissue for examination under a microscope--to confirm amyloidosis.
No effective treatment has been found to reverse the effects of amyloidosis. Combination drug therapy with melphalan (a cancer drug) and prednisone (an anti-inflammatory steroid drug) may improve organ function and survival rates by interrupting the growth of cells that produce amyloid protein. These are the same drugs used in chemotherapy to treat certain cancers, and they may have serious side effects, such as nausea and vomiting, hair loss, and fatigue.
DRA is relatively common in patients who have been on dialysis for more than 5 years, especially among the elderly. Dialysis membranes don't effectively remove the large, complex beta-2-microglobulin proteins from the bloodstream. As a result, blood levels become elevated, and deposits form in bone, joints, and tendons. DRA may result in pain, stiffness, and fluid in the joints. Patients with DRA may also develop hollow cavities, or cysts, in some of their bones; these may lead to unexpected bone fractures. Amyloid deposits may cause tears in ligaments and tendons (the tissue that connects the muscle to the bone). Most patients with these problems can be helped by surgical intervention.
Half of the people with DRA also develop a condition called
carpal tunnel syndrome, which results from the unusual buildup of
protein in the wrists. Patients with this disorder may experience
numbness or tingling, sometimes associated with muscle weakness, in
their fingers and hands. This is a treatable condition.
Amyloid may build up in the wrist and cause bone cysts or carpal tunnel syndrome.
|Unfortunately, no cure for DRA has been found, although a
successful kidney transplant may stop the disease from progressing.
However, DRA has caught the attention of dialysis engineers who are
attempting to develop membranes that can more efficiently remove
beta-2-microglobulin from the blood.
About the Kidney Failure SeriesThe NIDDK Kidney Failure Series includes six booklets and seven fact sheets that can help you learn more about treatment methods for kidney failure, complications of dialysis, financial help for the treatment of kidney failure, and eating right on hemodialysis. For free single printed copies of this series, please contact the National Kidney and Urologic Diseases Information Clearinghouse.
National Kidney and Urologic Diseases Information Clearinghouse
3 Information WayThe National Kidney and Urologic Diseases Information Clearinghouse (NKUDIC) is a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). The NIDDK is part of the National Institutes of Health under the U.S. Department of Health and Human Services. Established in 1987, the clearinghouse provides information about diseases of the kidneys and urologic system to people with kidney and urologic disorders and to their families, health care professionals, and the public. NKUDIC answers inquiries, develops and distributes publications, and works closely with professional and patient organizations and Government agencies to coordinate resources about kidney and urologic diseases.
Publications produced by the clearinghouse are carefully reviewed by both NIDDK scientists and outside experts. This fact sheet was reviewed by Glenn Chertow, M.D., University of California at San Francisco, and William J. Stone, M.D., Vanderbilt University.
This e-text is not copyrighted. The clearinghouse encourages users of this e-pub to duplicate and distribute as many copies as desired.
NIH Publication No. 01-4694
Posted: May 2001
Medical Tools & Articles:
- Risk Factor Center
- Medical Statistics Center
- Medical Treatment Center
- Prevention Center
- Medical Tests Center