In about 5% of cases, SPS is a paraneoplastic manifestation most often associated with antibodies against amphiphysin [10, 11] and in a single case against gephyrin [12]; in two of our patients with GAD-SPS, the disease was paraneoplastic which means that paraneoplastic SPS can be rarely seen within GAD-SD. This evidence concerns the gene AMPH and stiff-person syndrome.