Generalized Peripheric Nerve Hyperexcitability with Neuropathy: Case Series with Long-Term Outcome

Area of Science:

• Neurology
• Neuroimmunology

Background:

• Peripheric nerve hyperexcitability (PNH) syndromes are rare disorders characterized by continuous muscle overactivity resulting from spontaneous lower motor neuron discharges.
• These conditions present a diagnostic challenge due to their heterogeneous nature.

Observation:

• This case series describes four patients with PNH exhibiting painful cramps, generalized muscle twitches, and lower extremity weakness.
• All patients demonstrated neuropathy and neuromyotonic discharges on electrodiagnostic studies.
• One patient tested positive for uncharacterized neuropil antibodies, while the etiology remained undetermined in the cohort despite comprehensive investigations.

Findings:

• The study suggests a potentially high prevalence of neuropathy in PNH syndromes.
• Anti-neuronal antibody positivity and early diagnosis emerged as significant factors.
• One patient showed a positive response to immunotherapy, indicating its potential therapeutic role.

Implications:

• Early diagnosis and identification of anti-neuronal antibodies may improve prognoses for patients with PNH.
• Further research is warranted to elucidate the underlying mechanisms and optimize treatment strategies for these rare neurological conditions.