A case of dermato-fasciitis: amyopathic dermatomyositis associated with fasciitis

Amyopathic dermatomyositis (ADM) is characterized by the typical cutaneous features of dermatomyositis and minor involvement of the skeletal muscles. A 50-year-old woman had fever, reddening and pain in the distal part of all four limbs, and cutaneous findings such as Gottron's papules and periorbital heliotrope. She showed no muscle weakness or atrophy, and her serum creatine kinase was within the normal range. Electromyography showed no myopathic pattern. Magnetic resonance imaging (MRI) recorded abnormal hyperintensity in the fascia and muscle of the tibialis anterior. A biopsy from the tibialis anterior muscle showed fasciitis and mild myopathic changes with focal perivascular infiltration. This patient also presented with interstitial pneumonitis, although evaluation for malignancy was negative. With steroid therapy, her symptoms and MRI abnormality disappeared within 2 months. This case is therefore considered to be a variant of ADM, presenting as dermato-fasciitis.