Diagnostic efficacy of inflammatory markers in maternal and umbilical cord blood in histologic chorioamnionitis / 中华围产医学杂志

ABSTRACT

Objective To explore the clinical value of maternal and umbilical blood inflammatory markers,interleukin-6 (IL-6),neutrophil-to-lymphocyte ratio (NLR),C-reactive protein (CRP) and procalcitonin (PCT),in the diagnosis of histologic chorioamnionitis (HCA).Methods A total of 102 suspected chorioamnionitic cases were enrolled from January 2014 to July 2017.They were assigned into two groups based upon postpartum histopathological examination of placentaHCA group (48 cases) and control group (54 cases).Maternal and umbilical blood samples were collected for routine blood test and tested for IL-6,NLR,CRP and PCT levels.T,Mann-Whitney U or Chi-square (or Fisher's exact) test was used for data comparison.Meaningful indicators in maternal and umbilical cord blood were analyzed by logistic regression analysis and correlation analysis.At the same time,receiver operating characteristic (ROC) curve was drawn to evaluate their diagnostic values.Results (1) IL-6 level and NLR in maternal blood in HCA group were higher than those in control group [6.95 (2.40-13.50) vs 3.90 (2.30-9.20) pg/ml,Z=-5.147;5.03 (1.92-9.20) vs 3.94 (1.85-11.17),Z=-3.097;both P＜0.05],and the levels of white blood cells,neutrophile granulocytes,CRP and IL-6 as well as NLR in umbilical cord blood were also higher [(9.4± 2.0)× 109/L vs (8.6 ± 1.4)× 109/L,t=-2.522;(6.87t1.62)× 109/L vs (5.99± 1.26)× 109/L,t=-3.071;12.30 (0.50-89.04) vs 3.18 (0.50-88.93) mg/L,Z=-4.519;(8.78±2.56) vs (4.78±1.45) pg/ml,t=-7.025;(4.45±1.36) vs (3.78±1.22),t=-3.020;all P＜0.05].(2) Logistic regression analysis showed that elevated levels of IL-6 and NLR in maternal blood and CRP and IL-6 in umbilical cord blood were independent risk factors for HCA [OR (95％CI)1.65 (1.32-2.06),1.34 (1.02-1.77),1.05 (1.00-1.11) and 2.39 (1.72-3.32),all P＜0.05].Positive correlations were found between the levels of IL-6 in maternal and umbilical cord blood,and between NLR in maternal blood and CRP level in umbilical cord blood (correlation coefficient0.680 and 0.230,both P＜0.05).(3) IL-6 level in umbilical blood was of the greatest value in the diagnosis of HCA among all single markers,followed by IL 6 in maternal blood,CRP in umbilical blood and NLR in maternal blood [area under the ROC curve (AUC)0.904,0.796,0.760 and 0.678].When two indexes were combined,NLR in maternal blood+IL 6 in umbilical cord blood showed the highest diagnostic value,followed by,IL 6 in maternal blood+CRP in umbilical cord blood,IL-6+NLR in maternal blood and NLR in maternal blood+CRP in umbilical cord blood (AUC0.917,0.870,0.823 and 0.791).When three indexes was used in combination,the diagnostic value of IL-6 in maternal and umbilical cord blood+NLR in maternal blood was higher than that of IL-6 and NLR in maternal blood+CRP in umbilical cord blood (AUC0.919 and 0.836).(4) There were 13 cases (27.1％) with neonatal complications in HCA group and two (3.7％) in control group (P＜0.05).Conclusions Changes in NLR and IL-6 levels in maternal blood and NLR,IL-6 and CRP levels,and white blood cells and neutrophile granulocytes counts in umbilical cord blood are associated with HCA.The diagnostic efficacy of two indexes combined is superior to that of single index,while the combination of three indexes can significantly improve the diagnostic accuracy and authenticity.