Plasma CD59 concentrations are increased in preeclampsia with severe features and correlate with laboratory measures of end-organ injury

•Plasma CD59 concentration was increased in preeclampsia with severe features.•Urine CD59 concentration was decreased in preeclampsia with severe features.•Plasma CD59 levels correlated with increased blood pressure and end-organ injury.•Soluble CD59 levels may help characterize complement dysregulation in preeclampsia. Dysregulation of CD59 may lead to increased complement-mediated end-organ injury in preeclampsia. We sought to determine if soluble CD59 concentrations are altered in preeclampsia with severe features. Observational case-control study, which enrolled subjects prospectively from six centers in Colombia from 2015 to 2016. Cases had preeclampsia with severe features and controls were either healthy or had chronic hypertension, gestational hypertension, or preeclampsia without severe features. Trained coordinators collected clinical data, blood and urine. Analyses were by test of medians and Spearman’s correlation. Soluble CD59 concentration in plasma and urine, using enzyme linked immunosorbent assays. In total, 352 subjects were enrolled (104 cases; 248 controls). Compared to healthy women or those with other hypertensive disorders of pregnancy, women with preeclampsia with severe features had increased concentration of CD59 in plasma (P