Systemic muscular inflammation in a patient with recurrent orbital myositis.

We report a 53-year-old Japanese woman who had recurrent orbital myositis for 14 years. She exhibited mild muscle weakness in proximal limbs 13 years after the onset of orbital myositis. An electromyogram revealed myopathic potentials and denervation potentials in proximal limb muscles. Quadriceps biopsy showed infiltrates of mononuclear cells around intramuscular vessels and mild degenerative changes in muscle cells. These findings indicate that the present case belongs to the spectrum of localized nodular myositis.