Journal of Neurology

, Volume 261, Issue 1, pp 238–239 | Cite as

Cortical dysfunction in cerebellar ataxia with antibodies to glutamic acid decarboxylase

  • Neil G. SimonEmail author
  • Steve Vucic
  • Ronald Joffe
  • Matthew C. Kiernan
Letter to the Editors

Dear Sirs,

Antibodies against glutamic acid decarboxylase (GAD) have been identified in a number of neurological disorders, including cerebellar ataxia [1] and stiff-person syndrome (SPS) [2]. Recent studies have suggested a role for glutamic acid decarboxylase antibodies (GAD-Ab) in producing cortical dysfunction in SPS [3], but the pathogenesis of other neurological disorders with GAD-Ab remains to be fully elucidated. In order to further define the pathogenic role of GAD-Ab in cerebellar ataxia, the cortical modulating effects of GAD-Ab were evaluated in a patient with cerebellar ataxia with GAD-Ab.

A 52-year-old female, with a background of mature-onset type 1 diabetes mellitus, presented with 12 months of progressive cerebellar dysfunction characterised by gait and truncal ataxia, dysarthria, complex nystagmus, and left upper limb dysmetria and intention tremor. Cerebellar dysfunction was quantified using the Brief Ataxia Rating Scale, with a score of 14 out of a maximum of 30 [4]...


Baclofen Cerebellar Ataxia Glutamic Acid Decarboxylase Cortical Excitability Rest Motor Threshold 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Conflicts of interest

Dr. Neil Simon received funding from the National Health and Medical Research Council of Australia and the Motor Neurone Disease Research Institute of Australia (grant #1039520). The study was supported by a National Health and Medical Research Council Program Grant (#1037746). The authors declare that they have no conflicts of interest.

Ethical statement

The study protocol was approved by the South-Eastern Sydney and Illawarra Area Health Service Human Research Ethics Committee. Written consent was obtained from each subject.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Neil G. Simon
    • 1
    • 2
    Email author
  • Steve Vucic
    • 1
    • 3
  • Ronald Joffe
    • 4
  • Matthew C. Kiernan
    • 5
  1. 1.Neuroscience Research AustraliaRandwickAustralia
  2. 2.Prince of Wales Clinical SchoolUniversity of New South WalesSydneyAustralia
  3. 3.Western Clinical SchoolUniversity of SydneySydneyAustralia
  4. 4.Department of NeurologyRoyal North Shore HospitalSt LeonardsAustralia
  5. 5.Brain and Mind Research InstituteThe University of SydneyCamperdownAustralia

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