Autoimmune encephalitis with anti-IgLON5 and anti-GABAB-receptor antibodies: A case report

Medicine (Baltimore). 2019 May;98(20):e15706. doi: 10.1097/MD.0000000000015706.


Rationale: Anti-IgLON5 disease is a complex neurological illness which is characterized by progressive sleep and movement disorders and defined by specific autoantibodies to IgLON5. We here describe the first case of a patient with coexisting anti-IgLON5 as well as anti-γ-aminobutyric acid B (GABAB)-receptor antibodies and predominant clinical features of anti-IgLON5 disease.

Patient concerns: The patient initially presented with subacute symptoms of severe sleep disorder, gait stability, dysarthria, cognitive impairment, depressive episode and hallucinations.

Diagnoses: The patient was diagnosed with autoimmune encephalitis, based on clinical features and positive anti-IgLON5 antibodies in serum as well as in cerebrospinal fluid and anti-GABAB-receptor antibodies in serum only.

Interventions: Initially, the patient was treated with high dosages of methylprednisolone and subsequently with plasmapheresis. Due to the lack of clinical improvement immunosuppressive treatment with intravenous cyclophosphamide was initiated.

Outcomes: Following the first year of cyclophosphamide treatment, neurological examination revealed an improvement in gait instability, visual and acoustic hallucinations and sleep disorder.

Lessons: The case report demonstrates that anti-IgLON5 and anti-GABAB-receptor antibodies can coexist in the same patient whereas clinical leading symptoms are determined by those antibodies that were tested positive in cerebrospinal fluid.

Publication types

  • Case Reports

MeSH terms

  • Administration, Intravenous
  • Autoantibodies / blood
  • Cell Adhesion Molecules, Neuronal / blood*
  • Cell Adhesion Molecules, Neuronal / cerebrospinal fluid*
  • Cognitive Dysfunction / diagnosis
  • Cognitive Dysfunction / etiology
  • Cyclophosphamide / administration & dosage
  • Cyclophosphamide / therapeutic use
  • Depressive Disorder / diagnosis
  • Depressive Disorder / etiology
  • Dysarthria / diagnosis
  • Dysarthria / etiology
  • Encephalitis / diagnosis
  • Encephalitis / drug therapy
  • Encephalitis / immunology*
  • GABA-B Receptor Antagonists / blood*
  • Gait Disorders, Neurologic / diagnosis
  • Gait Disorders, Neurologic / etiology
  • Glucocorticoids / therapeutic use
  • Hallucinations / diagnosis
  • Hallucinations / etiology
  • Hashimoto Disease / diagnosis
  • Hashimoto Disease / drug therapy
  • Hashimoto Disease / immunology*
  • Humans
  • Immunosuppressive Agents / therapeutic use
  • Male
  • Methylprednisolone / administration & dosage
  • Methylprednisolone / therapeutic use
  • Middle Aged
  • Plasmapheresis / methods
  • Sleep Wake Disorders / diagnosis
  • Sleep Wake Disorders / etiology
  • Treatment Outcome


  • Autoantibodies
  • Cell Adhesion Molecules, Neuronal
  • GABA-B Receptor Antagonists
  • Glucocorticoids
  • IgLON5 protein, human
  • Immunosuppressive Agents
  • Cyclophosphamide
  • Methylprednisolone

Supplementary concepts

  • Hashimoto's encephalitis