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Effects of immunotherapy on motor cortex excitability in Stiff Person Syndrome
Simone Rossi1, Monica Ulivelli, Maria Malentacchi
1Dipartimento di Neuroscienze, Sezione Neurologia, University of Siena, Policlinico Le Scotte, Viale Bracci, 53100, Siena, Italy. Rossisimo@unisi.it
A number of cortical and spinal excitability variables have been tested in a patient with Stiff Person Syndrome (SPS), before and after immunotherapy with mycophenolate mofetil, intravenous immunoglobulin and corticosteroids, which normalized plasma levels of anti-GAD antibodies and dramatically improved the clinical picture. The overlapping time-course of neurophysiological, clinical and bio-umoral findings suggests that immunotherapy might have changed GABA/Glutamate balance at cortical level, favoring the former, as reflected by normalization of the startle reflex, lengthening of the cortical silent period and clear-cut reduction of intracortical facilitation to paired-pulse transcranial magnetic stimulation. This represents the first report investigating effects of immunotherapy on cortical excitability in SPS.
A number of cortical and spinal excitability variables have been tested in a patient with Stiff Person Syndrome (SPS), before and after immunotherapy with mycophenolate mofetil, intravenous immunoglobulin and corticosteroids, which normalized plasma levels of anti-GAD antibodies and dramatically improved the clinical picture. The overlapping time-course of neurophysiological, clinical and bio-umoral findings suggests that immunotherapy might have changed GABA/Glutamate balance at cortical level, favoring the former, as reflected by normalization of the startle reflex, lengthening of the cortical silent period and clear-cut reduction of intracortical facilitation to paired-pulse transcranial magnetic stimulation. This represents the first report investigating effects of immunotherapy on cortical excitability in SPS.
