Serum peripherin as a disease biomarker in hereditary transthyretin amyloidosis: a multicenter cohort study

Background: Hereditary transthyretin amyloidosis (ATTRv, v for variant) is a rare, progressive, and fatal multisystemic disease. Peripherin represents a promising biomarker for axonal damage in the peripheral nervous system (PNS). This study aims to investigate serum peripherin levels in symptomatic and presymptomatic ATTRv subjects, alongside serum neurofilament light chain (sNfL) levels, and their correlations with disease progression and severity. Methods: This multicenter, cross-sectional cohort study included 96 individuals with TTR gene variants (49 presymptomatic and 47 symptomatic ATTRv subjects) and 42 healthy controls (HCs). Serum peripherin levels were measured using a highly sensitive homebrew immunoassay, whereas sNfL levels were determined using a commercially available Simoa Neurology 2-Plex B assay. Statistical analyses included non-parametric Spearman correlations, Kruskal-Wallis ANOVA, ANCOVA, and binomial logistic regression. Results: Serum peripherin levels were elevated in both presymptomatic (p < 0.001) and symptomatic ATTRv groups (p < 0.001) compared to HCs. Peripherin levels did not correlate with age, sNfL levels, or clinical severity, but showed a strong discriminative ability between ATTRv and HCs (AUC = 0.83, sensitivity = 76%, specificity = 76%, p < 0.001). Conclusions: This study demonstrates that serum peripherin represents a promising biomarker for early detection of PNS damage in ATTRv, with elevated levels detectable even in presymptomatic stages.