Cold-evoked potentials in Fabry disease and polyneuropathy

Area of Science:

• Neurology
• Clinical Neuroscience
• Sensory Physiology

Background:

• Fabry disease (FD) and other polyneuropathies (PNP) involve small fiber damage, leading to cold-evoked pain and altered cold perception.
• Cold-evoked potentials (CEPs) offer a method to evaluate the integrity of thinly myelinated fibers and the spinothalamic tract.

Purpose of the Study:

• To evaluate the clinical utility of CEPs in patients with FD and PNP.
• To investigate the association of CEPs with pain, autonomic function, sensory deficits, and neuropathic signs.

Main Methods:

• CEPs were recorded from the hand and foot dorsum in patients with FD (n=16), PNP (n=21), and healthy controls (n=23).
• Quantitative sensory testing (QST), painDETECT questionnaire (PDQ), FabryScan, and autonomic nervous system measures were employed for comprehensive phenotyping.
• Statistical analyses included group comparisons and correlation analyses between CEP data and clinical measures.

Main Results:

• Abnormal CEPs were observed in a high percentage of both FD (87.5%) and PNP (85.7%) patients.
• CEPs significantly correlated with cold detection thresholds, pain scores (PDQ), and autonomic measures across all patient groups.
• Abnormal CEP latency in FD patients was linked to heart rate variability, while in PNP patients, CEP latency and amplitude correlated with pain and autonomic function.

Conclusions:

• Abnormal CEPs are associated with pain, neuropathic symptoms, and autonomic dysfunction in FD and PNP.
• CEPs provide a more comprehensive assessment of the sensory nervous system compared to QST alone, particularly for autonomic involvement.
• CEPs are a valuable tool for understanding the pathophysiology of small fiber neuropathy in conditions like Fabry disease and polyneuropathies.