Juvenile Idiopathic Inflammatory Myopathy in a Patient With Dyskeratosis Congenita Due to C16orf57 Mutation.

Dyskeratosis congenita (DC) is a rare inherited disorder characterized by reticular skin pigmentation, oral cavity leukoplakia, and nail dystrophy. A variety of noncutaneous (dental, pulmonary, gastrointestinal, neurological, genitourinary, ophthalmic, and skeletal) abnormalities also have been reported. An 8-year-old boy with DC developed juvenile idiopathic inflammatory myopathy. C16orf57 mutation was identified as a genetic cause of DC. Treatment with methylprednisolone was initiated, followed with methotrexate, prednisolone, and high-dose intravenous immunoglobulin treatment. This is the first report on a patient with juvenile idiopathic inflammatory myopathy and DC.