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Severe resting clonus caused by thyrotoxicosis in a 16-year-old girl with hereditary spastic paraparesis: A case report


  • Terence D. Sanger MD, PhD

    Corresponding author
    1. Department of Neurology and Neurological Sciences, Stanford University Medical Center, Stanford, California, USA
    • Stanford University Medical Center, Department of Neurology and Neurological Sciences, 300 Pasteur, Room A347, Stanford, CA 94305-5235
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A 16-year-old girl with a history of hereditary spastic paraparesis developed the subacute onset of severe clonus and new upper-extremity spasticity due to thyrotoxicosis. This case demonstrates the ability of hyperthyroid states to worsen symptoms of spasticity in a child with an underlying spastic disorder. It also demonstrates the importance of investigating for common systemic diseases as a cause of movement disorders even in children with underlying known genetic disorders. © 2004 Movement Disorder Society