Cardiac involvement in anti-GABA-B receptor encephalitis: a case report.

Area of Science:

• Neurology
• Immunology
• Cardiology

Background:

• Anti-gamma-aminobutyric acid B receptor (GABA-B R) encephalitis is a rare autoimmune disorder.
• It often presents with seizures and memory loss, frequently linked to small cell lung cancer.
• Cardiac involvement is rarely reported despite GABA-B R expression in the heart.

Purpose of the Study:

• To report a case of anti-GABA-B R encephalitis with extracerebral manifestation.
• To investigate potential cardiac involvement in this condition.

Main Methods:

• A 65-year-old man presented with status epilepticus.
• Diagnosis was confirmed by detecting anti-GABA-B R antibodies in serum and CSF.
• Autopsy was performed to examine brain, meninges, and cardiac tissue.

Main Results:

• The patient showed improvement with corticosteroids but died unexpectedly.
• Autopsy revealed autoimmune encephalitis and metastatic neuroendocrine carcinoma.
• Importantly, lymphocytic infiltration consistent with myocarditis was found in the heart.

Conclusions:

• This case expands the known spectrum of anti-GABA-B R encephalitis.
• It suggests a potential link between GABA-B R autoimmunity and myocardial inflammation.
• Cardiac monitoring may be beneficial for patients with anti-GABA-B R encephalitis, especially in paraneoplastic cases.