title: Glycine receptor autoimmune spectrum with stiff-man syndrome phenotype.
abstract: OBJECTIVE
  To determine whether glycine receptor α1 subunit-specific autoantibodies (GlyRα1-IgG) occur in a broader spectrum of brainstem and spinal hyperexcitability disorders than the progressive encephalomyelitis with rigidity and myoclonus phenotype recognized to date, and to ascertain disease specificity.
  
  
  METHODS
  Retrospective, case-control study.
  
  
  METHODS
  Mayo Clinic, Rochester, Minnesota, and University of Barcelona, Spain.
  
  
  METHODS
  Eighty-one patients with stiff-man syndrome phenotype, 80 neurologic control subjects, and 20 healthy control subjects.
  
  
  METHODS
  Glycine receptor α1-transfected cells to test serum or cerebrospinal fluid from cases and control subjects.
  
  
  METHODS
  Frequency of GlyRα1-IgG positivity among stiff-man syndrome phenotype cases and control subjects. Comparison of GlyRα1-IgG seropositive and seronegative cases.
  
  
  RESULTS
  Seropositive cases (12% of cases) included 9 with stiff-man syndrome (4 classic; 5 variant; 66% were glutamic acid decarboxylase 65-IgG positive) and 1 with progressive encephalomyelitis with rigidity and myoclonus. Immunotherapy responses were noted more frequently in GlyRα1-IgG-positive cases (6 of 7 improved) than in seronegative cases (7 of 25 improved; P= .02). The single seropositive control patient had steroid-responsive vision loss and optic atrophy with inflammatory cerebrospinal fluid.
  
  
  CONCLUSIONS
  Glycine receptor α1-IgG aids identification of autoimmune brainstem/spinal cord hyperexcitability disorders and may extend to the glycinergic visual system.
authors.affiliation: Department of Neurology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: McKeon
authors.forename: Eugenia
authors.initials: E
authors.lastname: Martinez-Hernandez
authors.forename: Eric
authors.initials: E
authors.lastname: Lancaster
authors.forename: Joseph Y
authors.initials: JY
authors.lastname: Matsumoto
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Harvey
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: McEvoy
authors.forename: Sean J
authors.initials: SJ
authors.lastname: Pittock
authors.forename: Vanda A
authors.initials: VA
authors.lastname: Lennon
authors.forename: Josep
authors.initials: J
authors.lastname: Dalmau
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D001323:Autoantibodies / Q000096:biosynthesis* / Q000235:genetics; D001933:Brain Stem / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D016022:Case-Control Studies; D002675:Child, Preschool; D005260:Female; D057809:HEK293 Cells; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D021122:Protein Subunits / Q000235:genetics / Q000276:immunology; D018009:Receptors, Glycine / Q000097:blood* / Q000235:genetics / Q000276:immunology; D012189:Retrospective Studies; D016750:Stiff-Person Syndrome / Q000235:genetics / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D021122:Protein Subunits; D018009:Receptors, Glycine