Predictive value of procalcitonin, C-reactive protein, and white blood cells for chorioamnionitis among women with preterm premature rupture of membranes

Objective To determine the predictive value of procalcitonin, C-reactive protein (CRP), and white blood cells (WBC) for chorioamnionitis among women with preterm premature rupture of membranes (PPROM). Methods A prospective cross-sectional study of all women with singleton pregnancy and PPROM admitted to a referral hospital in Shiraz, Iran, from 2016 to 2018. All women were hospitalized until delivery. The incidence of chorioamnionitis was recorded. Maternal serum CRP, procalcitonin, and WBC were measured on the day of admission and the day before termination of pregnancy. The diagnostic accuracy of each test was evaluated by receiver operator characteristic (ROC) curve analysis. Results Overall, 75 women with PPROM were included in the study. After termination of pregnancy, 34 (45.3%) were diagnosed with clinical chorioamnionitis. Those with chorioamnionitis had significantly higher serum levels of CRP both on admission (P=0.004) and before termination of pregnancy (P<0.001). The area under the curve for last CRP was 0.78 (95% confidence interval, 0.57-0.84), indicating moderate accuracy. Procalcitonin and WBC had low accuracy to predict chorioamnionitis. Conclusion Among CRP, procalcitonin, and WBC, maternal serum CRP was found to be the most accurate predictor of chorioamnionitis among women with PPROM.