PT - JOURNAL ARTICLE AU - Baizabal-Carvallo, José Fidel AU - Jankovic, Joseph TI - Stiff-person syndrome: insights into a complex autoimmune disorder AID - 10.1136/jnnp-2014-309201 DP - 2015 Aug 01 TA - Journal of Neurology, Neurosurgery & Psychiatry PG - 840--848 VI - 86 IP - 8 4099 - http://jnnp.bmj.com/content/86/8/840.short 4100 - http://jnnp.bmj.com/content/86/8/840.full SO - J Neurol Neurosurg Psychiatry2015 Aug 01; 86 AB - Stiff-person syndrome (SPS) is characterised by progressive rigidity and muscle spasms affecting the axial and limb muscles. Since its initial description in 1956, marked progress has been made in the clinical characterisation, understanding of pathogenesis and therapy of this disorder. SPS can be classified according to the clinical presentation into classic SPS and SPS variants: focal or segmental-SPS, jerking-SPS and progressive encephalomyelitis with rigidity and myoclonus. Most patients with SPS have antibodies directed against the glutamic acid decarboxylase, the rate-limiting enzyme for the production of the inhibitory neurotransmitter γ-aminobutyric acid (GABA). Antibodies directed against GABAA receptor-associated protein, and the glycine-α1 receptor can also be observed. Paraneoplastic SPS is commonly associated with antiamphiphysin antibodies and breast cancer. Treatment of SPS with drugs that increase the GABAergic tone combined with immunotherapy can improve the neurological manifestations of these patients. The prognosis, however, is unpredictable and spontaneous remissions are unlikely.