Dyshidrosis is associated with reduced amplitudes in electrically evoked pain-related potentials in women with Fabry disease.

OBJECTIVE: To investigate A-delta fiber conduction in mild to moderate Fabry disease (FD) patients using pain-related evoked potentials (PREP).

METHODS: In this case-control study we prospectively investigated 58 patients with mild to moderate FD and compared data with those of healthy controls. Small fiber function (quantitative sensory testing, QST and sympathetic skin response, SSR), morphology (intraepidermal nerve fiber density, IENFD), and electrical conduction (PREP) were assessed and correlated with sweating as major autonomic function disturbed in FD. Patients were further stratified for gender, disease severity as reflected by renal and cardiac function, and genetics.

RESULTS: An- or hypohidrosis (i.e. dyshidrosis) was reported by 7/32 (22%) women and 15/26 (58%) men with FD (p < 0.01). QST showed small fiber impairment in female and male patients regardless of clinical symptoms, while SSR was obtained in all patients except one man with hypohidrosis. IENFD was reduced in 50% of FD patients, with no differences between groups with and without autonomic symptoms. However, PREP amplitudes were reduced independent of the stimulation site only in female patients with dyshidrosis (p < 0.01). Genetics had no influence on PREP parameters.

CONCLUSION: A-delta fiber conduction investigated using PREP is impaired in mild to moderately affected female FD patients with clinical signs of hypohidrosis.

SIGNIFICANCE: Small fiber assessment in FD is of diagnostic value already in mild to moderate stages of disease.