Pediatric atypical hemolytic–uremic syndrome due to auto-antibodies against factor H: is there an interest to combine eculizumab and mycophenolate mofetil?

Abstract

Atypical hemolytic and uremic syndrome (aHUS), a thrombotic micro-angiopathy (TMA) caused by deregulation in the complement pathway, is sometimes due to the presence of anti-complement factor H (CFH) auto-antibodies. The "standard" treatment for such aHUS combines plasma exchange therapy and immunosuppressive drugs. Eculizumab, a monoclonal antibody that blocks the terminal pathway of the complement cascade, could be an interesting alternative in association with an immunosuppressive treatment for maintenance regimen. We report on two children, diagnosed with mildly severe aHUS due to anti-CFH antibodies, who were treated with the association eculizumab-mycophenolate mofetil (MMF). Neither side effects nor relapses were observed during the 3 years of follow-up; MMF was even progressively tapered and withdrawn successfully in one patient. The association of eculizumab and MMF appears to be an effective and safe option in pediatric cases of aHUS due to anti-CFH antibodies of mild severity.