P269 Small fiber assessment by sudoscan in transthyretin familial amyloid polyneuropathy treated patients – A longitudinal study

Abstract

Objective To prospectively assess small fiber involvement in Transthyretin familial amyloid polyneuropathy (TTR-FAP). Methods We studied 116 TTR-FAP Val30Met subjects (59 asymptomatic carriers, 45 tafamidis-treated, and 12 liver transplanted) at three time (t) points separated by a mean of 12.5(±4.2) and 11.5(±3.2) months between t1–t2 and t2–t3, respectively. Sural nerve action potential (SNAP), palmar and plantar sympathetic skin response (SSR) and electrochemical skin conductance (ESC) measured by Sudoscan in hands and feet were evaluated. Neuropathy Impairment Scale (NIS) and Body mass index (BMI) were recorded. Adjusted generalized linear model repeated measures was used for comparisons (level of significance set at 0.01). Results As expected, sural SNAP, plantar SSR, and feet and hands ESC, were significantly lower in tafamidis and transplanted groups (p Discussion Sudomotor function seems to decline over time among tafamidis-treated patients. Conclusions Small fiber neuropathy progression seems not to be totally halted by tafamidis treatment, as assessed with Sudoscan. Significance Sudoscan appears to be a non-invasive, easy and reproducible test to assess disease progression and treatment effectiveness in TTR-FAP.