Potential c-fiber damage in Wilson's disease

Objectives – To find out about potential involvement of the peripheral and autonomic nervous system in Wilson's disease (WD). Material and methods – Seventeen patients with laboratory proven WD were examined with quantitative sensory testing (QST) (thermal, pain and vibratory sensation), pupillometric evaluation and electrophysiological testing of basal ganglia motor function [frequency of most rapid alternating movements (MRAM), reaction time (RT), contraction time (CT)]. Results were compared with those obtained in 20 healthy controls. Results – After correction for multiple comparisons, patients with WD showed significantly higher thresholds for warm sensation [sural and peroneal nerve, thermal sensory limen (TSL), unpaired t-test]. Individual results were pathological in eight (peroneal) and nine (sural nerve) patients, respectively. Pupil function was not altered. Patients with WD showed significant slowing of MRAM and prolongation of RT and CT. There was no significant correlation between RT and QST results. Conclusions – These findings are compatible with a potential involvement of unmyelinated warm-specific C fibers in WD, independent from predominant basal ganglia motor dysfunction.