Immunotherapy-responsive limbic encephalitis with antibodies to glutamic acid decarboxylase

J Neurol Sci. 2014 Aug 15;343(1-2):192-4. doi: 10.1016/j.jns.2014.05.032. Epub 2014 May 27.

Abstract

Glutamic acid decarboxylase (GAD) has been recently identified as a target of humoral autoimmunity in a small subgroup of patients with non-paraneoplastic limbic encephalitis (NPLE). We present a patient with NPLE and positive anti-GAD antibodies who showed significant improvement after long-term immunotherapy. A 48-year old female was admitted with a two-year history of anterograde amnesia and seizures. Brain MRI revealed bilateral lesions of medial temporal lobes. Screening for anti-neuronal antibodies showed high anti-GAD titers in both serum and cerebrospinal fluid (CSF) with strong evidence of intrathecal production. The patient received treatment with prednisolone and long-term plasma exchange. During a 12-month follow-up, she exhibited complete seizure remission and an improvement in memory and visuo-spatial skills. Anti-GAD antibodies may serve as a useful marker to identify a subset of NPLE patients that respond to immunoregulatory treatment.

Keywords: Autoimmune; Glutamic acid decarboxylase; Limbic encephalopathy; Plasma exchange; Steroids; Treatment.

Publication types

  • Case Reports

MeSH terms

  • Antibodies / blood*
  • Antibodies / cerebrospinal fluid*
  • Aspartic Acid / analogs & derivatives
  • Aspartic Acid / metabolism
  • Choline
  • Cognition Disorders / etiology
  • Cognition Disorders / therapy
  • Creatine
  • Female
  • Glutamate Decarboxylase / immunology*
  • Humans
  • Immunotherapy / methods*
  • Limbic Encephalitis / blood
  • Limbic Encephalitis / cerebrospinal fluid
  • Limbic Encephalitis / complications
  • Limbic Encephalitis / therapy*
  • Magnetic Resonance Imaging
  • Middle Aged
  • Perceptual Disorders / etiology
  • Perceptual Disorders / therapy
  • Plasma Exchange / methods
  • Prednisolone / therapeutic use
  • Visual Perception / drug effects
  • Visual Perception / physiology

Substances

  • Antibodies
  • Aspartic Acid
  • N-acetylaspartate
  • Prednisolone
  • Glutamate Decarboxylase
  • Creatine
  • Choline