High frequency of calcinosis in juvenile dermatomyositis: a risk factor study.

OBJECTIVE To assess the frequency of calcinosis in patients with juvenile dermatomyositis, and the possible risk factors for that manifestation. METHODS Medical record review of 34 patients, with an emphasis on the following characteristics: demographic, clinical and laboratory data; type of treatment; adherence to treatment; disease course (monocyclic, chronic and polycyclic); and disease severity. Patients were divided into two groups as follows: those who developed calcinosis (up to the sixth month of follow-up and after six months of follow-up) and those who did not develop calcinosis. Twenty-seven patients underwent two nailfold capillaroscopies (NFC), which were considered altered when the scleroderma pattern was found. RESULTS The mean age of symptom onset of the 34 patients was 6.5 years, the time until diagnosis was 1.2 years, and 70% were females. Half of the patients had a monocyclic disease course, and only 14.7% had severe vasculitis. Almost 90% of the patients undergoing NFC showed a change on the first assessment, 74% showed a change on the second assessment, and the mean interval between both assessments was 1.6 year. Calcinosis was evidenced in 16 (47.1%) patients. No association was observed between the variables analyzed and the development of calcinosis. CONCLUSION No risk factors for calcinosis were identified in this study, although that complication was found in half of the patients with juvenile dermatomyositis studied.