Juvenile dermatomyositis: a 20-year retrospective analysis of treatment and clinical outcomes

Background: Juvenile dermatomyositis is a rare childhood multisystem autoimmune disease involving primarily the skin and muscles, and it may lead to long-term disability. This study aimed to describe the clinical course of juvenile dermatomyositis and determine if any early clinical or laboratory features could predict outcome.

Methods: Medical charts of patients aged ≤18 years and diagnosed with juvenile dermatomyositis (according to the criteria of Bohan and Peter) at the Pediatric Department, National Taiwan University Hospital, between 1989 and 2009 were reviewed. The endpoints for disease assessment were complete clinical response and complete clinical remission. Cox's proportional hazards model was fitted to identify important predictors of complete clinical remission.

Results: A total of 39 patients with juvenile dermatomyositis were reviewed. Two-thirds were females, and the mean age at disease onset was 81.97 ± 46.63 months. The most common initial presentations were Gottron's papule (82.1%) and muscle weakness (82.1%). After excluding one patient with an incomplete record, the remaining 31 patients who had muscle weakness were analyzed; among them, 22 (70.97%) achieved complete clinical response, but only six (19.4%) achieved complete clinical remission. Multivariate analysis showed that female sex, negative Gowers' sign at disease onset, and positive photosensitivity at disease onset were favorable factors to achieve complete clinical remission. Moreover, covariate-adjusted survival curves were drawn for making predictions of complete clinical remission. Only 13 (33.33%) patients were symptom free at the end of follow up, whereas the other 26 suffered from different kinds of complications. None of them developed malignancy, but two (5.13%) patients died during the follow-up period.

Conclusion: Factors such as male sex and Gowers' sign were unlikely to favor the achievement of complete clinical remission in juvenile dermatomyositis. Certain complications cannot be avoided, and thus more effective treatments and monitoring strategies are needed for better control of juvenile dermatomyositis.