An Unusual Case of Muscle Twitching: Its LGI1

Area of Science:

• Neurology
• Immunology

Background:

• Peripheral nerve hyperexcitability (PNH) syndrome is a rare autoimmune disorder.
• Leucin-rich glioma-inactivated 1 (LGI1) antibodies are implicated in certain neurological conditions.

Observation:

• A 50-year-old male presented with a two-month history of ascending paresthesias and continuous body twitching, accompanied by insomnia.
• Electromyography (EMG) indicated neuromyotonia, a hallmark of peripheral nerve hyperexcitability.

Findings:

• The patient was diagnosed with LGI1 antibody-associated PNH syndrome.
• Treatment with intravenous immunoglobulin and carbamazepine resulted in significant symptom improvement.

Implications:

• This case highlights the importance of identifying LGI1 antibodies in PNH syndrome.
• Effective treatment strategies involving immunotherapy and anticonvulsants can be employed for LGI1-associated PNH.