Isolated Leukocytosis to Predict Chorioamnionitis in Preterm Prelabor Rupture of Membranes Between 24 and 33 Weeks [21K

Abstract

INTRODUCTION: During Prelabor Premature Rupture of Membranes (PPROM), Chorioamnionitis is an indication for delivery; hence prompt diagnosis is of major relevance for maternal and neonatal outcome. Chorioamnionitis can affect about 40-70% of preterm births with premature rupture of membranes. The objective of this study is to assess the relevance of isolated leukocytosis in predicting Chorioamnionitis during PPROM between 24 and 33 weeks. METHODS: In this retrospective study performed at our institution from 2014 to 2017, 161 pregnancies with PPROM where selected. The last white blood cell count (WBC) obtained before delivery was used as an indicator for Chorioamnionitis, which was diagnosed by placental histologic findings. Patients were classified as PPROM without Chorioamnionitis and with Chorioamnionitis with and without Leukocytosis (>15,000 cells/ml). Time of when Celestone was given in relation to the last WBC obtained, indication for delivery and presence of other signs of infection including fever were documented. RESULTS: 81 patients had PPROM without Chorioamnionitis; only 9 (11%) had leukocytosis. From the patients with Chorioamnionitis, 50 (62.2%) had leukocytosis (Average WBC 17,500) and 30 (37.8%) did not (Average WBC 9,900). 85% of the patients with leukocytosis had Chorioamnionitis. Only 2.5% of patients with Chorioamnionitis had fever and 20% of the patients with Chorioamnionitis were delivered due to suspected infection. Sensitivity for Leukocytosis was 62.5% with specificity of 88.8%. Receiver operating characteristic AUC was 0.723 (p value<0.001, 95% confidence interval 0.6396 to 0.8066). CONCLUSION: Isolated leukocytosis can become a strong predictor for Chorioamnionitis if repeated periodically during PPROM between 24 and 33 weeks.