Various Manifestations of Rheumatic Disorders: Case 4 Idiopathic Dermatomyositis

A 76-year-old woman complained of progressive proximal muscle weakness; achy pain in the buttocks, thighs, and calves; and lilac discoloration of her eyelids, cheek, nose, knuckles, and fingernails. Examination confirmed heliotrope skin changes and disclosed moderate weakness in the limb and girdle musculature. The patient’s levels of muscle enzymes, including creatine kinase, aldolase, aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase, were elevated, as was her erythrocyte sedimentation rate. An electromyogram revealed increased exertional activity, fibrillation potentials, and a typical myopathic pattern. Muscle biopsy was performed, and the findings were consistent with inflammatory myositis. Evaluation for an underlying malignancy yielded negative results. The diagnosis of idiopathic dermatomyositis was based on 4 criteria: clinical picture, electromyographic findings, elevated serum creatine kinase level, and biopsy report. The patient was treated with prednisone(, 60 mg/d, and was given physical therapy. Three months later, her strength had improved by 80%.

(Case and photograph courtesy of Dr Gavin I. Awerbuch.)