title: Glutamic acid decarboxylase autoantibody syndrome presenting as schizophrenia.
abstract: BACKGROUND
  Glutamic acid decarboxylase (GAD) is the rate-limiting enzyme converting glutamate into γ-aminobutyric acid. Impaired GAD function can alter motor, cognitive, and behavioral function. Anti-GAD antibodies (GADAbs) can cause several neurological disorders. However, the association between anti-GADAbs and pure psychosis, without seizures or focal neurological deficits, is not well defined.
  
  
  METHODS
  A 19-year-old woman with recent-onset psychotic disorder was diagnosed with schizophrenia. Brain magnetic resonance imaging and cerebrospinal fluid analysis were normal. Serum anti-GADAb titers were elevated. Brain biopsy showed subcortical gliosis and microglia-macrophage infiltration. The clinical syndrome improved with immune therapy.
  
  
  CONCLUSIONS
  Severe psychosis and mild cognitive decline without other neurological features, meeting the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revision diagnostic criteria for schizophrenia, can result from brain inflammation associated with elevated serum anti-GADAbs.
authors.affiliation: Department of Neurology, New York University School of Medicine, New York, NY, USA. mna1024231@aol.com
authors.forename: Souhel
authors.initials: S
authors.lastname: Najjar
authors.forename: Daniel
authors.initials: D
authors.lastname: Pearlman
authors.forename: David
authors.initials: D
authors.lastname: Zagzag
authors.forename: John
authors.initials: J
authors.lastname: Golfinos
authors.forename: Orrin
authors.initials: O
authors.lastname: Devinsky
mesh_terms: D020274:Autoimmune Diseases of the Nervous System / Q000175:diagnosis* / Q000201:enzymology*; D003937:Diagnosis, Differential; D005260:Female; D005968:Glutamate Decarboxylase / Q000172:deficiency / Q000276:immunology*; D006801:Humans; D012559:Schizophrenia / Q000175:diagnosis* / Q000201:enzymology* / Q000276:immunology; D055815:Young Adult
chemical_list: D005968:Glutamate Decarboxylase