UPAR, IL-33, and ST2 Values as a Predictor of Subclinical Chorioamnionitis in Preterm Premature Rupture of Membranes

Abstract

Preterm premature rupture of membranes (PPROM) is defined as rupture of membrane that happens before the onset of labor and 37 weeks. Subclinical intrauterine infection is major etiological factor in the pathogenesis that increases mortality and morbidity associated with PPROM. This study was performed to evaluate the levels of maternal serum urokinase plasminogen activator receptor (uPAR), ST2 and interleukin (IL)-33 in PPROM and its relation with maternofetal infectious and morbidity. A total of 74 pregnant women, of which 49 with PPROM between 24 and 34 weeks gestation, and 25 normal pregnant women without PPROM were included in the study. Study group was seperated into 2 subgroups as PPROM and PPROM-histological chorioamnionitis (PPROM-HC). The blood samples were taken before the any medication. The mean serum IL-33, ST2, and uPAR values in the PPROM-HC group were significantly higher than PPROM and control group. The cut-off values of IL-33, ST2, and uPAR were determined as 5.2, 2 and 6.4 ng/mL, respectively. A cut-off value of IL-33 of 5.2 ng/mL, the cut-off of ST2 of 2 ng/mL and the cut-off of uPAR of 6.4 ng/mL showed similar sensitivity, specificity to IL-6 and the better sensitivity and specificity as compared to C-reactive protein and total leucocyte count in predicting infection in PPROM. We evaluated the predictive value of uPAR, ST2 and IL-33 in PPROM and we concluded that all of them can be used as reliable biomarkers to determine infection without any clinical signs but it is necessary to be studied in different cohort groups and infectious diseases.