Preeclampsia is a leading cause of morbidity and mortality during pregnancy. The variability of clinical features suggests that preeclampsia is not a single disease. Atypical hemolytic uremic syndrome, resulting from defective regulation of the alternative complement pathway, is less well known and may be mistaken for preeclampsia.
We describe a woman with atypical hemolytic uremic syndrome who was given the diagnosis of gestational hypertension during her first pregnancy and preeclampsia and hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome followed by thrombotic thrombocytopenic purpura and hemolytic uremic syndrome during her second pregnancy, before the correct diagnosis of atypical hemolytic uremic syndrome was recognized in the postpartum period of her third pregnancy. The patient was treated with anticomplement therapy and had a rapid improvement.
This case illustrates the importance of distinguishing atypical hemolytic uremic syndrome from preeclampsia.