Wild-type (senile) amyloidosis other diagnostic studies

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Aditya Ganti M.B.B.S. [2]

Overview

Other diagnostic studies that help in diagnosing wild-type (senile) amyloidosis include histopathological analysis and genetic testing.

Other diagnostic studies that help in diagnosing wild-type (senile) amyloidosis include histopathological analysis and genetic testing.^[1]


Other Diagnostic Studies
Histopathological analysis	Endomyocardial biopsy (EMB) with histopathology remains the gold standard for diagnosis of cardiac amyloidosis. Histopathology demonstrates deposition of amorphous deposits of amyloid fibrils in the heart. The binding of Congo red stain to the deposited amyloid fibrils leads to characteristic apple-green birefringence under polarized light microscopy and an intense yellow-green fluorescence is seen when binding to thioflavin. Precursor protein identification can be accomplished by immunohistochemistry, electron microscopy, or mass spectrometry (preferred), depending upon institutional expertise. Adjunctive laboratory tests to rule out AL include assaying for other organ dysfunction (e.g., proteinuria, alkaline phosphatase) and directly measuring the circulating light chains in plasma. EMB is associated with risks of complications such as: Ventricular free-wall perforation Arrhythmia Conduction abnormalities
Genetic testing	DNA sequencing for the transthyretin gene Absence of amino acid sequence abnormalities by mass spectrometry is consistent with wild-type (senile) amyloidosis Presence of a pathologic mutation Predict sites of organ involvement Family history

↑ Damy T, Deux JF, Moutereau S, Guendouz S, Mohty D, Rappeneau S, Guellich A, Hittinger L, Loric S, Lefaucheur JP, Plante-Bordeneuve V (December 2013). “Role of natriuretic peptide to predict cardiac abnormalities in patients with hereditary transthyretin amyloidosis”. Amyloid. 20 (4): 212–20. doi:10.3109/13506129.2013.825240. PMID 23964755.