How is amyloidosis diagnosed?

Amyloidosis is sufficiently uncommon that primary care physicians may not recognize when and how to test for this disease. The patient is often subjected to endless, time consuming and expensive testing. If amyloidosis is suspected, you should discuss this with your doctor. Tissue that shows amyloid deposits on "Congo-red staining" is the only true way to confirm the suspicion of amyloidosis and is always abnormal. To obtain tissue, the least invasive means should be used first, such as stomach fat aspirate, oral or rectal mucosa. Stomach fat aspirates have been shown to be 80% accurate in Primary and Hereditary forms and 50% accurate in Secondary. In addition, the patient can be examined for a plasma cell dyscrasia by immunofixation electrophoresis of the blood and urine along with a bone marrow biopsy with immunohistochemical staining of plasma cells for κ and λ light chains. In addition, a Free Light Chain (FLC) blood test must be done. Having an initial FLC level will help in monitoring the disease in the future. If a hereditary form of the disease is suspected, genetic testing is required to confirm the type. This is a simple blood test where the genes are analyzed to determine which mutation is present. This blood test can be done my mail to an amyloidosis center.