Kaposi's sarcoma associated with adult dermatomyositis

Abstract

We report a case involving a 73-year-old Saudi man diagnosed with dermatomyositis who subsequently developed Kaposi's sarcoma one month later. He had difficulty in rising from a chair and increased leg weakness while climbing stairs or walking. He was unable to comb his hair and had greater dysphagia with liquids than with solid foods. Laboratory tests showed elevated liver enzyme and creatine kinase levels. Right quadriceps muscle biopsy indicated inflammatory myopathy, which was consistent with adult dermatomyositis. We administered 1-g/day methylprednisolone intravenously for 3 days, followed by 60-mg oral prednisolone daily, which led to significant improvements in his muscle strength and dysphagia symptoms. The creatine phosphokinase level normalized. Computed tomography and endoscopic examinations did not reveal any evidence of an underlying malignancy. The patient was discharged and underwent close monitoring at a rheumatology clinic. We subsequently added 50-mg oral azathioprine daily to the treatment regimen. At one month after emergency room presentation, multiple new dusky violaceous macules and plaques appeared on his chest, face, upper back, neck, and upper limbs. A biopsy of one of these lesions showed findings consistent with Kaposi's sarcoma. He was referred to an oncology center for chemotherapy, following which his skin lesions significantly regressed. Dermatomyositis may be considered a paraneoplastic syndrome of Kaposi's sarcoma.