EFFICACY OF LEVETIRACETAM IN A CASE OF STIFF-PERSON SYNDROME - CASE REPORT

Abstract

Stiff-person syndrome (SPS) is a rare neurologic disorder characterized by severe axial and proximal limb rigidity and unexpected spasms due to continuous motor unit activity. There are several SPS variants, including stiff trunk syndrome, stiff limbs syndrome, progressive encephalomyelitis with rigidity, SPS-plus, and paraneoplastic SPS. These syndromes are often found in association with other autoimmune disorders such as diabetes mellitus in more than one thirds of all cases, and, less commonly, those caused by antithyroid, antinuclear and antiparietal cell antibodies. Glutamic acid decarboxylase autoantibodies (anti-GAD) are found in around 60 to 80 % of SPS cases. GAD is a cytoplasmic enzyme that accelerates the conversion of glutamic acid to gamma-aminobutyric acid (GABA), an inhibitory neurotransmitter present in the brain and spinal cord. GAD is synthesized mainly in presynaptic GABAergic neurons in the central nervous system and in the beta cells in the islets of Langerhans in the pancreas. Benzodiazepines and baclofen have been used as the main therapeutic interventions addressing the muscle rigidity and spams in these cases. Here, we described a patient with anti-GAD positive SPS with marked improvement of muscle rigidity and spams after use of a new anticonvulsivant drug (levetiracetam).