To investigate the value of combined detection of serum calcitonin (PCT), matrix metalloproteinase-9 (MMP-9) and soluble intercellular adhesion molecule 1 (sICAM-1) in the diagnosis of chorioamnionitis.

From March 2019 to December 2021, a total of 83 women with premature rupture of membranes (PROM) in single pregnancy in Hebei Youfu Hospital were selected, retrospectively. According to the placental pathology and clinical manifestations of chorioamnionitis, patients were divided into four groups; 19 patients with clinical and pathological findings consistent with chorioamnionitis were classified as clinical + pathological group, 17 patients without obvious clinical manifestations but with placental pathology diagnosed as chorioamnionitis were classified as pathological group, 20 patients with certain clinical manifestations but negative pathological diagnosis were classified as clinical group. The clinical manifestations and pathological diagnosis of the remaining 27 patients were negative, and they were enrolled in control group. The levels of serum PCT, MMP-9 and ICAM-1 among different groups of postpartum women were compared, and Spearman correlation analysis was used to analyze the correlations between serum PCT, MMP-9 and ICAM-1 among postpartum women with chorioamnionitis. The diagnostic value of chorioamnionitis of the three indicators alone and combination were analyzed by receiver operating characteristic curve (ROC).

There were significant differences in the levels of serum PCT, MMP-9 and sICAM-1 in each group of postpartum women (F = 35.907, 75.807, 44.363, all P < 0.001). The levels of PCT, MMP-9 and sICAM-1 in the clinical + pathological group were significantly higher than those of the other three groups (all P < 0.001). However, there was no significant difference in the levels of PCT, MMP-9 and sICAM-1 between pathological group and clinical group (t = 0.328, P = 0.671; t = 0.449, P = 0.551; t = 0.173, P = 0.826). Spearman correlation analysis showed that serum PCT of cases with chorioamnionitis was positively correlated with MMP-9 and sICAM-1 (r = 0.420, P = 0.001; r = 0.343, P = 0.010), while serum MMP-9 was positively correlated with sICAM-1 (r = 0.424, P = 0.001), both with significant differences. The diagnostic values of serum PCT, MMP-9 and sICAM-1 levels for chorioamnionitis were analyzed by diagnosing placental pathology as the gold standard. When the PCT threshold was 61.020 pg/ml, its specificity and sensitivity were 87.2% and 83.3%, respectively, and the AUC was 0.917 (95%CI: 0.825-0.955); When the MMP-9 threshold was 111.412 ng/ml, the specificity and sensitivity were 72.3% and 97.2%, respectively, and the AUC was 0.927 (95%CI: 0.837-0.962); When the sICAM-1 threshold was 1 149.635 ng/ml, the specificity and sensitivity were 83.0% and 86.1%, respectively, and the AUC was 0.879 (95%CI: 0.798-0.902). The specificity and sensitivity of the combined detection of the above three indicators were 93.1% and 93.4%, respectively, with the AUC of 0.951 (95%CI: 0.874-0.969). The combined detection of AUC showed no significant difference compared with PCT and MMP-9 alone (Z = 0.500, P = 0.617; Z = 0.901, P = 0.368). The combined detection of AUC was significantly higher than that of sICAM-1 alone (Z = 3.158, P = 0.018).

Combined detection of serum PCT, MMP-9 and sICAM-1 has good sensitivity and specificity in assisting in diagnosis of chorioamnionitis.