Case Report: Sexual dysfunction as an early clue of autonomic involvement in hereditary transthyretin amyloidosis with TTR c.210T>A (p.Ser70Arg) variant

Hereditary transthyretin amyloidosis (hATTR) is an autosomal dominant amyloidosis caused by pathogenic variants in the TTR gene. It causes multisystem damage, including peripheral and autonomic neuropathy as well as cardiac amyloid involvement. Its highly heterogeneous clinical phenotype poses challenges for early recognition. We report the case of a 54-year-old male patient with hATTR caused by the TTR c.210T>A (p.Ser70Arg) variant. The clinical course was characterized by progressive multisystem involvement, with sexual dysfunction as the earliest identifiable prodromal symptom. After several years of misdiagnosis, the disease ultimately progressed to advanced-stage hATTR with cardiac amyloid involvement complicated by severe peripheral and autonomic neuropathy. A noninvasive diagnosis was established through technetium-99m pyrophosphate (99mTc-PYP) myocardial scintigraphy, exclusion of plasma cell dyscrasia, and genetic testing, followed by initiation of targeted disease-modifying therapy with tafamidis. This case report aims to enhance clinicians' recognition of early autonomic prodromal symptoms in this rare subtype and to enrich the real-world clinical data on this variant in China.