Peripheral nervous system electrodiagnostic abnormalities in predominantly Hispanic Multiple Sclerosis patients.

Area of Science:

• Neurology
• Neuroscience
• Clinical Electrophysiology

Background:

• Peripheral nervous system (PNS) abnormalities in Multiple Sclerosis (MS) are infrequently reported, with limited understanding of their prevalence.
• Existing knowledge is primarily based on case reports and small case series, lacking comprehensive electrodiagnostic data.

Purpose of the Study:

• To determine the prevalence of electrodiagnostic abnormalities in a cohort of predominantly Hispanic Multiple Sclerosis patients.
• To investigate the occurrence of demyelinating neuropathies, axonal peripheral neuropathy, and sympathetic dysfunction in MS.

Main Methods:

• An observational, cross-sectional study involving 18 MS patients and 18 age- and height-matched healthy controls.
• Electrodiagnostic assessments included nerve conduction studies (NCS), electromyography (EMG), and sympathetic skin response (SSR).
• Data collection was prospective, including demographic and MS-specific characteristics, irrespective of clinical suspicion for neuropathy.

Main Results:

• High prevalence of electrophysiological axonal polyneuropathy (77.8%) and autonomic dysfunction (100% with prolonged SSR latencies) was observed in MS patients.
• 85.6% of patients with axonal polyneuropathy reported sensory symptoms; one patient was diagnosed with previously unrecognized CIDP.
• Autonomic symptoms, including bladder abnormalities and blood pressure fluctuations, were reported by 72.2% of patients.

Conclusions:

• Electrodiagnostic abnormalities, particularly axonal polyneuropathy, are more prevalent in MS patients than previously thought.
• Further investigation is warranted to explore the link between axonal polyneuropathy and central axonopathy in MS neurodegeneration.
• Identifying common etiologies may lead to improved understanding and targeted treatments for MS with PNS involvement.