Systemic Types of Amyloid

SYSTEMIC TYPES OF AMYLOID

Primary amyloidosis has amyloid light chain (AL) amyloid, whose fibrillary pro-tein is made of kappa or lambda light chains. Primary amyloidosis may be seen in plasma cell disorders (multiple myeloma, B-cell lymphomas, etc.) but most cases occur independent of other diseases.

Reactive systemic amyloidosis (secondary amyloidosis) has amyloid-associatedprotein, whose precursor is serum amyloid A (SAA), an acute phase reactant produced by the liver which is elevated with ongoing chronic inflammation and neoplasia. Reactive systemic amyloidosis can be seen with a wide variety of chronic diseases, including rheumatoid arthritis, systemic lupus erythematosus, tuberculo-sis, bronchiectasis, osteomyelitis, inflammatory bowel disease, and cancer.

Familial Mediterranean fever has AA type amyloid with fibrillary protein composedof serum amyloid A (SAA). This autosomal recessive disease is characterized by recur-rent inflammation, fever, and neutrophil dysfunction. Gain of function mutations of pyrin are present.

Hemodialysis-associated amyloidosis has Aβ2M type amyloid with precursor pro-tein β2-microglobulin. This form of amyloidosis may cause carpal tunnel syndrome and joint disease.