Histologic Characterization of Amyloidosis Based on Amyloid Proteins
Using the immunohistochemical technique, variable types of amyloid fibril protein can be easily identified on formalin-fixed and paraffin-embedded tissue sections. In this study, histopathologic features of systemic amyloidosis in 104 autopsy cases were reviewed and investigated whether there was a relationship between the chemical types of amyloid proteins and the tissue distribution of amyloid deposits. Morphologically, the most characteristic feature was that all cases of AA amyloidosis examined showed “vascular amyloidosis” and the small arteries of many organs were mainly affected by amyloid. Although diffuse deposition of amyloid in AA type was found in the thyroid gland and mucosal layers of the alimentary tracts, no amyloid deposition was found in the parenchyma of the liver, spleen and/or adrenal. In the kidney, nodular deposition of amyloid was found in the glomeruli.
On the other hand, 44% of AL cases were “parenchymal amyloidosis” and the space of Disse or the red pulp of the spleen were diffusely occupied by amyloid deposits. In the alimentary tracts, a characteristic finding was diffuse deposition of amyloid in the muscular layers. In the glomeruli, linear amyloid deposits were found along the basement membrane. The vascular amyloidosis was also found in AL.
From the present study, it is concluded that there are some significant differences in the manner of amyloid deposition between AA and AL amyloidosis.
KeywordsAmyloid Deposit Alimentary Tract Amyloid Protein Systemic Amyloidosis Portal Triad
Unable to display preview. Download preview PDF.
- 1.P. Westermark, K. H. Johnson, and P. Pitkaenen: Systemic amyloidosis: a review with emphasis on pathogenesis. Appl. Pathol., 3:55 (1985).Google Scholar
- 4.S. Fujihara: Differentiation of amyloid fibril proteins in tissue sections. Two simple and reliable histological methods applied to fifty-one cases of systemic amyloidosis. Acta Pathol. Jpn., 32:771 (1982).Google Scholar