RESUMO
Inclusion body myositis is a disease of striated skeletal muscle of unclear etiopathogenesis. Its diagnosis is difficult. Corticosteroids and immunosuppressants are of limited efficacy. Positive responses to intravenous immune globulins have recently been reported in a few patients. We used a CYBEX 6000 isokinetic dynamometer to evaluate the efficacy of intravenous immune globulin therapy in a patient with inclusion body myositis. Measurements were done at the flexors and extensors of the knee, at baseline and four and eight months after treatment initiation. A course of intravenous immune globulins (2 g per course) was given every month for five months then every two months. Isokinetic muscle strength measured at an angular speed of 180 degrees/second increased by more than 41% at both knees. As compared with muscle imaging studies (computed tomography, X-ray absorptiometry, ultrasonography, magnetic resonance imaging), isokinetic strength testing has the advantage of providing data on functional improvements under treatment.
