Dermatológia pre prax 1/2017

How can dermatologists improve the prognosis of children with juvenile dermatomyositis?

Juvenile dermatomyositis (JDM) is a rare systemic connective tissue disease of childhood. JDM has prognostically severe complications (lipoatrophy, dystrophic calcinosis). These are considered to be due to late diagnosis or insufficiently agressive treatment. The incidence of JDM is only 2-4 cases per 1 million children per year. In the years 2013-2016, we diagnosed JDM in 6 girls in our centre. This unusually high incidence was due to delayed diagnosis in some patients. Characteristic skin lesions (Gottron papules, heliotropic rash, malar rash) were present in all. Significant muscle weakness was found in 3, became apparent upon muscle testing in 2 and was completely absent in 1 patient. In 2 children, muscle enzymes were not elevated. Muscle MRI and nailfold capillaroscopy reliably identified patients with JDM, thus eliminating the need for invasive diagnostic procedures (EMG, muscle biopsy). The delayed diagnosis in some cases was due an incoplete clinical and laboratory picture and misdiagnosis as psoriasis, subacute lupus erythematosus and porphyria. JDM is a rare disease with severe prognosis that is dependent on early diagnosis and agressive treatment. Skin changes are characteristic and, unlike most other symptoms, present in all patients. Early recognition of JDM is essential and has prognostic implications.

Keywords: juvenile dermatomyositis, children, Gottron papules, capillaroscopy, dermatoscope