Background: Mycophenolate mofetil (MMF) has been introduced as a novel immunosuppressive agent in systemic lupus erythematosus (SLE) and is effective in patients refractory to other agents. However, data on the use of MMF on the paediatric onset SLE are scarce.

Methods: We studied five girls with SLE – diagnosed at the age of 11.1-12.6 years – all of them with joint and skin, four with renal (1 WHO II, 3 WHO IV) and three with cerebral involvement. Four of the girls received initial methylprednisolone pulses, three of them had cyclophosphamide courses and one was additionally treated with immunoadsorption. Three patients had maintenance therapy over 29-46 months with azathioprine and oral corticosteroids and showed frequent relapses; two patients with severe renal and cerebral disease received initial MMF. The dose of MMF was 1.2+ 0.15 g/m² BSA/day (max. 2g), the median follow-up period was 15.8 (range 12-18) months.

Results: During MMF-therapy we observed a marked reduction in disease activity (SLEDAI) and less relapse episodes (0.30 versus 1.28 per year). The prednisolone dose per day could be tapered, the renal function stayed stable. Leukocyte counts and C3c-complement levels raised, proteinuria and anti-dsDNA antibody levels were reduced without change in ANA-levels.

In 79 months of treatment no severe side effects of MMF occurred, only mild viral infects (herpes labialis, warts) were noted. One patient required a dose reduction because of gastrointestinal discomfort.

Conclusion: MMF appears to be a safe and effective alternative immunosuppressant also for the paediatric population with renal and extra- renal SLE.