Peripheral neuropathy in multiple system atrophy with autonomic failure.

Area of Science:

• Neurology
• Neuroscience
• Pathology

Background:

• Multiple system atrophy (MSA) is a neurodegenerative disorder characterized by autonomic failure, which can present with peripheral neuropathy.
• The specific mechanisms and pathological features of peripheral neuropathy in MSA, particularly the Shy-Drager syndrome variant, require further elucidation.

Observation:

• Two patients diagnosed with MSA, exhibiting autonomic failure and peripheral neuropathy, underwent detailed clinical and pathological examination.
• Electromyography (EMG) and sural nerve biopsy were performed to assess neuromuscular system involvement.

Findings:

• Histological analysis of the sural nerve biopsy revealed a significant reduction in large myelinated fibers.
• Unmyelinated axons in the sural nerve were observed to be completely spared.
• This pattern suggests that the sympathetic nervous system contributes minimally to the unmyelinated fiber population in the human sural nerve.

Implications:

• Peripheral nerve damage, specifically affecting large myelinated fibers, may be a common feature of the Shy-Drager syndrome.
• These findings contribute to understanding the neuropathological spectrum of MSA and its impact on the peripheral nervous system.
• Further research is warranted to explore the clinical significance and diagnostic utility of these nerve findings in MSA.