Juvenile dermatomyositis

A 16 year old girl is referred to the dermatology department because of complaints of progressive sunken skin lesions on arms and legs. Besides that, she also mentions chronic paronychia and erythematosquamous plaques on the face and upper back, which were formerly diagnosed and treated as psoriasis plaques. After interrupting the local corticosteroids, a clear heliotrope rash and shawl sign appeared. Capillaroscopy demonstrated a scleroderma pattern and besides the erythema and swelling of the nail folds she also displayed discrete gottron papules. A clinical suspicion of dermatomyositis rose. Because of complaints of muscle strain in the upper limbs, we performed an MRI. This did not show any muscle abnormalities, but confirmed the loss of subcutaneous fat tissue beneath the sunken skin lesions. A blood examination subsequently showed aberrant liver tests and MDA5 positivity. This confirmes the diagnose of dermatomyositis and in fact MDA5 positive dermatomyositis is known to have little muscle complaints and more prominent skin lesions. Five percent of cases also develop interstitial lung disease. Therefore our patient was referred to the pneumology department for further examination (lung function, HRCT). To exclude cardiac complications EKG and echocardiography was planned. In the meanwhile a treatment with methotrexate and hydroxychloroquine was started.

L. De Paepe (UZG)