Stiff-Person Syndrome: A Review

Abstract

Stiff-person syndrome is a rare autoimmune neurologic disorder characterized by progressive muscular rigidity and painful muscle spasms predominantly affecting the axial and the proximal limb muscles. Most patients with stiff-person syndrome have antibodies directed against the glutamic acid decarboxylase, the rate-limiting en-zyme for the production of inhibitory neurotransmitter gamma-aminobutyric acid. Paraneoplastic stiff-person syndrome is commonly associated with anti-amphiphysin antibodies and breast cancer. Treatment of stiff-person syndrome with drugs that increase the GABAergic tone, including the benzodiazepines, combined with immu-notherapy can improve the neurological manifestations of these patients. However, the prognosis is unpredictable and spontaneous remissions are unlikely. The literature on this topic is still scarce and, as it is a rare entity, it is poorly rec-ognized and probably underdiagnosed. This review article will describe important updates and organize the existing information about this topic.