Classification of Amyloidosis by Immunohistochemical Method and Potassium Permanganate Reaction: Correlation Between Morphology, Chemical Types and Clinical Features

Abstract

Systemic amyloidosis is a rare disorder, which usually occurs in aged people with a poor prognosis. Forty-five patients with amyloidosis were studied by light microscopy with Congo red staining, potassium permanganate reaction and immunohistochemistry. The biopsy sites were abdominal fat, rectum, lung, bone marrow, liver, pleura, duodenum, gallbladder, colon, oral cavity, larynx, thyroid and skin. The patients were classified according to immunohisto-chemistry and Congo red staining results after potassium permanganate treatment. Thus, 21 of 45(46.7%) cases were classified as AA (amyloid A protein), and 24(53.3%) cases were classified as AL(amyloid light chain) amyloidosis. This study suggests that the association of these two techniques, potassium permanganate reaction and immunohistochemical stain, is more reliable than clinical data alone in distinguishing between AA and AL amyloidosis.