potassium-permanganate and Cardiomyopathies

Congo red screening of 27,052 routine biopsy specimens from 22,827 patients over a 5 1/2-year period in the Department of Pathology, University of Malaya detected 186 cases of amyloidosis. The categories of amyloidosis encountered and their prevalences in relation to each other were: systemic AL (5.9%); systemic AA (3.2%); isolated atrial (14%); primary localized cutaneous (7.5%); other primary localized deposits (3.2%); localized intratumour (58%); and dystrophic (8.6%). A third of patients with systemic AL amyloidosis had coexistent immunocyte abnormality. The commonest underlying pathology for systemic AA amyloidosis was leprosy. Notable among the types of localized amyloidosis revealed by this study were isolated atrial amyloidosis, which appeared to complicate chronic rheumatic heart disease, and intratumour amyloidosis complicating nasopharyngeal carcinoma. Other tumours in which amyloid deposits were observed included basal cell carcinoma, islet cell tumour and medullary carcinoma of the thyroid. Dystrophic amyloidosis was observed in fibrotic tissues, such as damaged cardiac valves and osteoarthritic joints. Heredofamilial amyloidosis, senile systemic amyloidosis and degenerative cerebral amyloidosis were notably absent from this study.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Amyloid; Amyloidosis; Cardiomyopathies; Child; Humans; Immunoglobulin kappa-Chains; Immunoglobulin lambda-Chains; Immunohistochemistry; Malaysia; Microscopy, Electron; Middle Aged; Neoplasms; Potassium Permanganate; Prevalence; Skin Diseases

A simple and reproducible histochemical method for distinguishing different chemical types of amyloid is described. The method is based on the affinity of amyloid for Congo red dye after exposure to potassium permangenate and dilute sulfuric acid. The permanganate method represents a modification of the Romhanyi trypsin technique. It yields comparable results while obviating some of the technical difficulties associated with the latter method. The permanganate reaction was applied to a series of amyloid samples of known amino acid composition, to amyloid samples fixed in a variety of different preservatives, and to tissues obtained at autopsy from 67 amyloidosis patients whose disease had been previously subclassified on the basis of clinical presentation and autopsy observations. This method distinguished amyloid protein AA from other varieties of amyloid and proved effective when applied to amyloid samples preserved in any of several commonly used fixatives. This simple histochemical method proved useful in subclassifying amyloid type in the patient series particularly when used in conjunction with the available clinical history and the organ distribution of amyloid accumulation.

Topics: Amyloidosis; Cardiomyopathies; Congo Red; Histocytochemistry; Humans; Liver; Lung; Male; Middle Aged; Multiple Myeloma; Potassium Permanganate; Spleen; Tendons; Trypsin