Success of Eculizumab in the Treatment of Atypical Hemolytic Uremic Syndrome

Background: Disorders of complement regulation are the most important etiology of atypical hemolytic uremic syndrome (aHUS). Recent studies demonstrate that eculizumab is beneficial in long-term aHUS treatment. We present a series of children with aHUS resistant to/dependent on plasma exchange (PE) who were treated with eculizumab.

Methods: This was a retrospective study in which data were retrieved from the medical files of children who had received PE as treatment for aHUS. The data retrieved included age, sex, presenting symptoms, presence of diarrhea/vomiting, hospitalization duration, laboratory data on admission and follow-up, need for transfusion or dialysis, response to PE, response to eculizumab and outcome.

Results: Of the 15 children diagnosed with aHUS in 2011 and 2012 in our departments, ten were resistant to, or dependent on, plasma therapy and treated with eculizumab; these children were enrolled in the study. Three patients had relapses, and seven had a new diagnosis. Nine children had oliguria or anuria, and eight required dialysis. Hypertension was observed in six patients. Neurologic involvement developed in six patients, with the symptoms including seizures, loss of balance, vision loss and severe confusion. Five and five patients were resistant to and dependent on plasma therapy, respectively. Following the start of eculizumab treatment, all patients achieved full recovery of renal function and hematologic parameters.

Conclusions: In our ten pediatric patients with aHUS who did not respond to PE, eculizumab was a lifesaving therapy and improved their quality of life. Early eculizumab use was a rescue therapy for renal function. Our results show that eculizumab is an effective treatment for aHUS. However, more studies are needed on the long-term efficacy and safety of eculizumab in children with aHUS and to determine the optimal duration of treatment.