Laboratory markers to identify acute histological chorioamnionitis in febrile parturients undergoing epidural analgesia: a retrospective study

Background This study aimed to investigate the effect of the pathological staging of acute histological chorioamnionitis (HCA) on laboratory indicators and to conduct further studies to reassess the threshold values used by clinicians to identify acute HCA in febrile parturients undergoing epidural analgesia. Methods A retrospective study of febrile mothers receiving epidural analgesia at Nanjing Maternal and Child Health Care Hospital from January 1, 2018 to December 31, 2018. The participants were grouped by the progression of acute HCA, and the laboratory parameters were compared between groups. The ability of C-reactive protein (CRP), neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), and monocyte-leukocyte ratio (M%), alone or in combination, to identify acute HCA in febrile parturients undergoing epidural analgesia was assessed using logistic regression and ROC curves. Results The area under the curve (AUC) of the best logistic regression model predicting HCA climbed to 0.706 (CRP + MLR). Maternal CRP, NLR, and MLR significantly and progressively increased with the progression of acute HCA (p < 0.0001). Based on the ROC curves, the following thresholds were selected to define increased laboratory indicators for identifying acute HCA: CRP [greater than or equal to] 6.90 mg/L, NLR [greater than or equal to] 11.93, and MLR [greater than or equal to] 0.57. In addition, the AUC of the best logistic regression model predicting HCA [greater than or equal to] stage 2 was 0.710, so these inflammatory markers were more precise in predicting HCA [greater than or equal to] stage 2. Conclusion Increased CRP ([greater than or equal to] 6.90 mg/L), NLR ([greater than or equal to] 11.93), and MLR ([greater than or equal to] 0.57) may help clinicians to identify early potential acute HCA in febrile parturients receiving epidural analgesia and to monitor progression to optimize clinical treatment options. Trial registration The study was registered in the Chinese Clinical Trial Registry on November 24, 2021 ( Keywords: Biomarkers, C-reactive protein, Epidural hyperthermia, Histological chorioamnionitis, Monocyte-lymphocyte ratio, Neutrophil-lymphocyte ratio, Placental pathology, Pathological staging