Objectives: To investigate safety and efficacy of MMF in patients with severe or MTX-refractory juvenile localized scleroderma. Methods: Consecutive juvenile localized scleroderma patients undergoing systemic treatment were included in a retrospective longitudinal study. Patients treated with MMF because they were refractory or intolerant to MTX (MMF-group) were compared with responders to MTX (MTX-group). Disease activity was assessed by Localized Scleroderma Cutaneous Assessment Tool and thermography. Disease course was established on the number of relapses and treatment changes. Relapse-free survival was examined by Kaplan-Meier analysis. Results: MMF and MTX groups included 22 and 47 patients, respectively. No significant difference in demographics, follow-up duration and treatment before diagnosis was observed between groups. The most represented clinical subtypes in the MMF-group were pansclerotic morphea and mixed subtype (P = 0.008 and P = 0.029, respectively), and linear scleroderma of the face in the MTX-group (P = 0.048). MMF was started because of MTX resistance (18 patients), relapse during MTX tapering/withdrawal (3 patients) and anaphylaxis to MTX (1 patient). After mean 9.4 years of follow-up, 90.9% of patients on MMF and 100% of those on MTX had inactive disease. No significant difference in relapse-free survival between the groups was found (P = 0.066, log-rank test), although MMF likely induced more persistent remission. MMF was well tolerated and combination of MMF and MTX did not increase its efficacy. Conclusion: The present study adds strong evidence on the efficacy and tolerance of MMF in severe and/or MTX-refractory juvenile localized scleroderma. Further controlled studies are needed to prove its efficacy as first line treatment.
