Dermatomyositis and Whipple's disease

A 11-year-old boy presented with a 3-year history of a skin rash typical of juvenile dermatomyositis, and a 2-month history of mild proximal weakness, myalgia, and weight loss. A quadriceps biopsy showed perifascicular fibre atrophy, focal necrosis and regeneration, immunohistochemical labelling for HLA-1 on the surface of the fibres, and focal C5-9 deposition in capillari es. Macrophages with diastase-resistant. PAS-positive cytoplasm were presen t. Ultrastructural studies showed electron dense and membranous debris, The patient's symptoms responded to intravenous immunoglobulin and oral predni solone. Four months after discontinuing prednisolone, the patient developed cardiac failure, ventricular tachycardia, and a recurrence of his rash. Th e 16S ribosomal RNA specific for Tropheryma whippelii was identified by pol ymerase chain reaction (PCR) analysis in skeletal and cardiac muscle. The m yalgia and shin rash responded to prednisolone and oral co-trimoxazole, and the tachycardia is controlled by oral verapamil. This patient appears to h ave a novel association of juvenile dermatomyositis and Whipple's disease. (C) 2000 Elsevier Science B.V. All rights reserved.