potassium-permanganate and Waldenstrom-Macroglobulinemia

It is widely accepted that amyloidosis in Waldenström's macroglobulinemia (WM) is exclusively due to amyloid light-chain deposition. However, only a small number of previous reports have actually characterized the type of amyloid in WM. We now report the third patient with WM and amyloid A protein (AA) amyloidosis. This patient developed malabsorption, nephrotic syndrome, and orthostatic hypotension. AA was immunohistochemically demonstrated in the rectal biopsy. In conjunction with previous examples of AA amyloidosis, the present report raises the possibility that AA amyloidosis may also occur in WM patients.

Topics: Aged; Amyloidosis; Coloring Agents; Congo Red; Fatal Outcome; Humans; Male; Potassium Permanganate; Serum Amyloid A Protein; Waldenstrom Macroglobulinemia

The potassium permanganate method and the unlabeled immunoperoxidase (PAP) method were applied for distinguishing different types of amyloid fibril proteins in conventionally fixed, paraffin-embedded tissue sections obtained from fifty-one autopsied cases of systemic amyloidosis and three control cases of well-analysed fibril proteins. All of the eighteen cases "sensitive" to permanganate treatment, whose amyloid deposits lost completely their affinity to Congo red and birefringence under polarized light, were shown to have AA antigenic determinants by the PAP method. Meanwhile, all of the remaining thirty-three "resistant" cases, where Congo red affinity and birefringence were retained at various degree even only in minimal areas, were negative for AA antigenicity. This indicated the feasibility of potassium permanganate method for the identification of AA protein based on this criterion of "sensitivity". Twenty-eight cases were classified as AA, A lambda, A kappa or AA+[A kappa] the remaining twenty-three cases were unclassified, and there were some discrepancies between the preliminary clinicopathological classification and the protein nature of the amyloid. It is important to differentiate the types of amyloid fibril protein of individual patients because the expedience of selective therapeutic approaches had been suggested. The two methods applied herein are handy and useful for this purpose.

Topics: Adult; Aged; Amyloid; Amyloidosis; Child; Female; Histocytochemistry; Humans; Immunoenzyme Techniques; Male; Middle Aged; Multiple Myeloma; Potassium Permanganate; Staining and Labeling; Waldenstrom Macroglobulinemia