{
  "abstract": "Background Anti-gamma-aminobutyric acid B receptor (GABA-B R) encephalitis is an uncommon autoimmune disorder typically presenting with seizures, memory impairment and a frequent paraneoplastic association with small cell lung carcinoma. Although GABA-B Rs are expressed in cardiac tissue, extracerebral manifestations have rarely been described.Case presentation A 65-year-old man presented with status epilepticus. Cerebrospinal fluid (CSF) analysis revealed mild lymphocytic pleocytosis and type 3 oligoclonal bands. Anti-GABA-B R antibodies were detected in serum and CSF, confirming the diagnosis of autoimmune encephalitis. The patient improved after high-dose intravenous corticosteroids but died unexpectedly during recovery. Autopsy revealed perivascular CD3-positive lymphocytic infiltration in the brain and meninges, consistent with autoimmune encephalitis, and metastatic neuroendocrine carcinoma compatible with a pulmonary primary. Notably, CD3-positive lymphocytic infiltration was also found within myocardial fibres, consistent with lymphocytic myocarditis.Conclusions This case broadens the recognised spectrum of anti-GABA-B R encephalitis and raises the possibility of cardiac involvement in this disorder. The presence of GABA-B Rs in cardiomyocytes offers a potential link between receptor autoimmunity and myocardial inflammation. Although causality cannot be established, these findings suggest that cardiac monitoring may be advisable in patients with anti-GABA-B R encephalitis, particularly in paraneoplastic contexts.",
  "authors": [
    {
      "affiliations": [
        "Neuroimmunology and Multiple Sclerosis Unit, Hospital Universitario de Girona Doctor Josep Trueta, Girona, Spain"
      ],
      "name": "Rosa Ferrer Tarrés"
    },
    {
      "affiliations": [
        "Neuroimmunology and Multiple Sclerosis Unit, Hospital Universitario de Girona Doctor Josep Trueta, Girona, Spain",
        "Neurodegeneration and Neuroinflammation Research Group, IDIBGI, Girona, Catalonia, Spain"
      ],
      "name": "Alexis García Sarreón"
    },
    {
      "affiliations": [
        "Pathology Service, Hospital Universitario de Girona Doctor Josep Trueta, Girona, Spain"
      ],
      "name": "Francisco Pozo Ariza"
    },
    {
      "affiliations": [
        "Neuroimmunology and Multiple Sclerosis Unit, Hospital Universitario de Girona Doctor Josep Trueta, Girona, Spain",
        "Neurodegeneration and Neuroinflammation Research Group, IDIBGI, Girona, Catalonia, Spain"
      ],
      "name": "Jorge Gutiérrez Naranjo"
    },
    {
      "affiliations": [
        "Neuroimmunology and Multiple Sclerosis Unit, Hospital Universitario de Girona Doctor Josep Trueta, Girona, Spain",
        "Neurodegeneration and Neuroinflammation Research Group, IDIBGI, Girona, Catalonia, Spain"
      ],
      "name": "Ariadna Gifreu-Fraixinó"
    },
    {
      "affiliations": [
        "Neuroimmunology and Multiple Sclerosis Unit, Hospital Universitario de Girona Doctor Josep Trueta, Girona, Spain",
        "Neurodegeneration and Neuroinflammation Research Group, IDIBGI, Girona, Catalonia, Spain"
      ],
      "name": "Almudena Boix-Lago"
    },
    {
      "affiliations": [
        "Neuroimmunology and Multiple Sclerosis Unit, Hospital Universitario de Girona Doctor Josep Trueta, Girona, Spain",
        "Neurodegeneration and Neuroinflammation Research Group, IDIBGI, Girona, Catalonia, Spain"
      ],
      "name": "Gary Álvarez-Bravo"
    }
  ],
  "title": "Cardiac involvement in anti-GABA-B receptor encephalitis: a case report",
  "uid": "29fea7dc-f6ac-5878-b44a-49ac844a9a00"
}