Epidemiology of variant transthyretin amyloidosis at a reference center in Argentina

MARIA SOLEDAD SAEZ; ADELA AGUIRRE; DIEGO PEREZ DE ARENAZA; PATRICIA SORROCHE; NUCIFORA, ELSA MERCEDES; MARIA LOURDES POSADAS MARTINEZ

MOLECULAR GENETICS AND GENOMICS

SPRINGER HEIDELBERG

Lugar: HEIDELBERG; Año: 2021

1617-4615

AbstractBackground: In Argentina, there is limited data of prevalence of variant transthyretin amyloidosis (ATTRv) and phenotype-genotype correlation. The laboratory of Hospital Italiano de Buenos Aires (HIBA) is a reference center fortransthyretin (TTR) gene sequencing. The Institutional Amyloidosis Registry(RIA) enable us to characterize people with ATTRv. Our aim was to describe theprevalence of TTR mutations at a reference center in Argentina and the phenotypic presentations of patients with ATTRv included in an institutional registry.Methods: Retrospective cohort study of consecutive patients with genetic variants in the TTR gene identified from 2012 to 2019 in the laboratory. We collectedall phenotypic characteristics of patients who were clinically evaluated by HIBAdoctors.Results: Five hundred seventy-six patients tested, 141 positive: p.Val50Met107, p.Thr80Ala 16, p.Ala117Ser 9, p.Phe84Leu 2, p.Ile127Val 2, p.Tyr134Cys 2,p.Ala56Pro 2, p.Val142Ile 1. Only 20 patients were clinically evaluated. The meanage at diagnosis was 54 years; 70% had family history with a pedigree medianof 4. Mutations were p.Thr80Ala 9, p.Val50Met 6, p.Ala56Pro 2, p.Val142Ile 1,p.Phe84Leu 1, and p.Tyr134Cys 1. Eleven patients presented polyneuropathy,11 had gastrointestinal compromise, six patients had autonomic compromise, sixpresented cardiac symptoms and four patients presented ocular involvement.Conclusion: We present the first prevalence report of TTR mutations in a reference center of amyloidosis in Argentina. The most frequent genetic variantwas p.Val50Met. Our data show considerable phenotypic heterogeneity in thepatients with ATTRv.