Amyloidosis

Abstract

Seventy-three autopsied cases of amyloidosis were analyzed and certain concepts and manifestations of amyloidosis reviewed. A suggested clinical classification of amyloidosis is:.I. Primary amyloidosis (no predisposing disease):.a. Generalized.b. Familial.c. Respiratory:.1. Tumorous, single or multiple.2. Diffuse.II. Secondary amyloidosis (with predisposing disease).III. Senile cardiac amyloidosis.IV. Amyloidosis secondary to multiple myeloma.V. Tumorous amyloidosis, excluding respiratory.The exact chemical composition of amyloid is unknown. However, it consists of one or more proteins in combination with polysaccharides. The process by which amyloid is formed may be related to an immune mechanism. Primary amyloidosis occurs in middle aged males. It is a polysystemic disease with predominant manifestations of renal, cardiac, gastrointestinal and, in the familial form, peripheral nerve involvement. Mucous membranes, skin, skeletal muscle and endocrine glands are often involved. Nodular or diffuse amyloidosis confined to the respiratory tract has been reported frequently. Secondary amyloidosis may occur at any age. The chief manifestation is albu-minuria in one of the many diseases known to precede secondary amyloidosis. Other frequent findings are urinary casts, enlarged liver, spleen and kidneys. Senile cardiac amyloidosis occurs in elderly patients, with the amyloid predominantly located in interstitial areas of the myocardium. Amyloidosis occurs in 15% of multiple myeloma patients. Plasma cell proliferation has been frequently noted in primary amyloidosis suggesting that plasma cells may play a fundamental role in amyloid formation even in those cases not associated with multiple myeloma. Biopsy of the kidney, liver, bone marrow, skin or mucosa is the best method of confirming the diagnosis.