Classification of Amyloid Syndromes from Tissue Sections Using Antibodies Against Various Amyloid Fibril Proteins: Report of 142 Cases

Abstract

To identify the chemical nature of amyloid fibril proteins in tissue sections, various formalin-fixed organs from 142 patients with amyloid were investigated with a panel of antisera directed against different purified amyloid fibril proteins from representative generalized amyloid syndromes.

Using anti-AA, Aλ, Aκ, AF, and ASc₁ antisera, 112 of 114 generalized amyloidoses (98%) and 120 of all 142 cases (85%) could be identified by either the indirect or the unlabeled immunoperoxidase method. Untypeable cases were usually localized or organ-limited forms of amyloid and may well be amyloid types which have not yet been identified.

The clinical diagnoses correlated well with the immunohistochemical definition of the amyloid type. Most of the 50 identified AA-amyloid syndromes, therefore, were associated with recurrent inflammatory diseases, predominantly different forms of arthritis. Surprisingly enough, no underlying diseases was found in 7 of the 50 AA cases (14%).

Most of the 41 Aλ and the 11 Aκ cases were B-cell neoplasms or idiopathic amyloidosis with plasma cell dyscrasias. Eight cases with senile cardiovascular amyloid and 10 with the cross-reacting amyloid polyneuropathy were identified.

Our data, therefore, demonstrate that almost all generalized and some more localized forms of amyloid can be identified with the panel of antisera against amyloid fibril proteins presented in this study.

This study was supported by Sonderforschungsbereich 0207, LP-12 and LP-13, Munich.