A Case of Stiff Person Syndrome

We describe a case of confirmed stiff person syndrome in an 86-year-old woman who initially presented for acute right lower-extremity pain and swelling. Her symptoms developed 10 days after her right foot was penetrated by a sewing needle. Her hospital course was complicated by progressive ascending spasms of the right upper and lower extremities, back, neck, and facial muscles, as well as intermittent hypoxia. She experienced some symptomatic improvement after treatment of suspected tetanus with tetanus immune globulin, a 10-day course of metronidazole, and aggressive antispasmodic management. She also was found to have high positive (>250 IU/mL) titers of antiglutamic acid decarboxylase antibodies in her serum and cerebrospinal fluid. Because both were greater than quantifiable thresholds, the results raised concern for an autoimmune cause of her symptoms. She was admitted to another hospital shortly after discharge for worsening respiratory distress in the setting of encephalopathy without muscle stiffness. Although her presentation is suggestive of stiff person syndrome, rapid progression of her symptoms is unusual for the typical course of the disease. We discuss several potential causes for her symptoms, including autoantibodies and infection from her needle-stick injury. We address in detail the features of her presentation concerning for the phenomenon of localized tetanus and the disease known as stiff person syndrome.