Mycophenolate mofetil in juvenile dermatomyositis: a case series

The objective of this study was to report the use of Mycophenolate Mofetil (MMF) in Juvenile Dermatomyositis (JDM). A retrospective chart review of children diagnosed with JDM having received MMF was performed. Response was evaluated 3 months after the onset of MMF by comparing muscle strength and steroid dosage before and after treatment. A good response was defined by global improvement concerning weakness and fatigability as evaluated subjectively by the physician along with a gain of at least 4 points on each of 2 muscle testings (Manual Muscle Testing, MMT and Childhood Myositis Assessment Score, CMAS) and/or a decrease of >15% of the corticosteroid dosage. Eight patients were identified. Except for one, all had received MMF secondary to an initial therapy of conventional immunosuppressants. Six patients showed good response by our predefined criteria. Changes of muscle testing scores ranged between +0 to +21 points (mean = +10.6) for the MMT and between +3 and +11 (mean = +7) for the CMAS. Corticosteroid tapering varied from 0 to 50%, with a mean of 18%. In most cases, follow-up was available for many months (up to 26); overall, we observed only one complication: a transient neutropenia in a patient concurrently receiving another immunosuppressant. This small series is the first published report on the use of MMF in JDM and suggests it is safe. Prospective larger studies are required to further elucidate the use of MMF in JDM.