Complement Inhibitor Eculizumab in Atypical Hemolytic Uremic Syndrome

BACKGROUND AND OBJECTIVES: Atypical hemolytic uremic syndrome (aHUS) is associated with a congenital or acquired dysregulation of the complement alternative pathway that leads to continuous complement activation on host cells causing inflammation and damage. Eculizumab, a humanized mAb against complement protein C5, inhibits activation of the terminal complement pathway. DESIGN, SETTING, PARTICIPANTS, however, after normalization of complement activity, aHUS recurred and ultimately led to anuric end-stage renal failure. CONCLUSIONS: In this patient, complement inhibition by eculizumab temporarily terminated the microangiopathic hemolytic activity. Nevertheless, renal damage as a result of preceding and subsequent aHUS activity resulted in end-stage renal failure; therefore, therapeutic success may depend on early administration of eculizumab. The optimal duration of treatment may be variable and remains to be determined.