Maternal Serum Interleukin-6: A Non-Invasive Predictor of Histological Chorioamnionitis in Women with Preterm-Prelabor Rupture of Membranes

OBJECTIVE

To assess the added value of maternal serum levels of IL-6 in women with preterm-prelabor rupture of membranes (PPROM) as a non-invasive test for the prediction of histological chorioamnionitis (HCA).

METHODS

This was a prospective cohort study of pregnant women between 20 + 0 and 36 + 6 weeks of gestation with a confirmed diagnosis of PPROM. Logistic regression models were created for the prediction of HCA and compared by assessing the improvement in their Naegelkerke R2 as a measure of goodness of fit. Predictive performance of all models was assessed by receiver operating characteristics curve (ROC) analysis and compared by the DeLong method.

RESULTS

From 47 women with PPROM, 31 (66%) developed HCA. Maternal serum IL-6 ≥19.5 pg/dL was the best cut-off point for the prediction of HCA (OR = 15; 95% CI: 3.6-61; p < 0.01). A model comprising maternal characteristics and IL-6 ≥19.5 pg/dL showed an area under the curve of 0.85 (95% CI: 0.74-0.95), significantly improving the previous models of IL-6 ≥19.5 pg/dL (R2: 23.3 vs. 34.1%; p = 0.01) or maternal characteristics (R2: 8.4 vs. 34.1%; p < 0.01).

CONCLUSIONS

A model comprising maternal serum levels of IL-6 plus maternal characteristics proves to be a good non-invasive predictor of HCA.

Circulating Angiogenic Factors and Urinary Prolactin as Predictors of Adverse Outcomes in Women With Preeclampsia

Preeclampsia is characterized by an imbalance in angiogenic factors. Urinary prolactin (PRL) levels and its antiangiogenic PRL fragments have been associated with disease severity. In this study, we assessed whether these biomarkers are associated with an increased risk of adverse maternal and perinatal outcomes in preeclamptic women. We studied 501 women with preeclampsia attended at a tertiary care hospital. Serum concentrations of soluble fms-like tyrosine kinase-1 (sFlt-1), placental growth factor (PlGF), and soluble endoglin (sEng), as well as urinary PRL levels, were measured by enzymed-linked immunosorbent assay. Antiangiogenic PRL fragments were determined by immunoblotting. The risk for any adverse maternal outcome and for having a small-for-gestational-age infant was higher among women with sFlt-1/PlGF ratios, sEng, and urinary PRL level values in the highest quartile (odds ratios ≥2.7), compared with the lowest quartile. Both urinary PRL levels and the presence of antiangiogenic PRL fragments were more closely associated with the risk of specific adverse maternal outcomes (placental abruption, hepatic hematoma or rupture, acute renal failure, pulmonary edema, maternal death, and need for endotracheal intubation, positive inotropic drug support, and hemodialysis; odds ratios ≥5.7 and ≥4.7, respectively) than either sFlt-1/PlGF ratio or sEng alone. We concluded that in preeclamptic women at the time of initial evaluation, sFlt-1/PlGF ratio and sEng are associated with increased risk of combined adverse maternal outcomes. However, urinary PRL concentrations and its antiangiogenic fragments appear to be better predictors of an adverse maternal outcome and may be useful for risk stratification in preeclampsia.

Urinary prolactin as a reliable marker for preeclampsia, its severity, and the occurrence of adverse pregnancy outcomes

CONTEXT

It has been proposed that preeclampsia may result from of an imbalance in angiogenic factors. Although prolactin (PRL) is mainly related to lactation, it is also involved in other biological functions, including angiogenesis.

OBJECTIVE

Our objective was to determine the relationship among preeclampsia, serum and urinary PRL (uPRL) levels, and excretion of antiangiogenic PRL fragments in urine.

STUDY DESIGN

Using a cross-sectional design, uPRL and serum PRL levels, and the presence of PRL isoforms were determined in 546 pregnant women: 207 healthy pregnant, 124 with gestational hypertension, 48 with mild preeclampsia, and 167 with severe preeclampsia (sPE).

RESULTS

uPRL concentrations were significantly (P < 0.001) higher in preeclampsia (11.99 ng/mg creatinine) than in healthy pregnancy (0.20 ng/mg creatinine) and gestational hypertension (0.19 ng/mg creatinine), and were even higher in sPE compared with mild preeclampsia (21.20 vs. 2.77 ng/mg creatinine, respectively; P < 0.001). Antiangiogenic PRL fragments (14-16 kDa) were detected in 21.6% of urine samples from women with sPE but in none from other groups. Patients with hemolysis, elevated liver enzymes, low platelet count syndrome, and/or eclampsia, placental abruption, acute renal failure, and pulmonary edema exhibited highest uPRL concentrations (P < or = 0.028) and frequency of antiangiogenic PRL fragments in urine (P < or = 0.036). High-serum PRL levels were associated with sPE independently of gestational age, proteinuria, and prolactinuria (P = 0.032).

CONCLUSIONS

Preeclampsia is characterized by increased uPRL excretion. uPRL concentrations and their isoforms appear to be suitable markers to assess the severity of preeclampsia and occurrence of adverse outcomes. PRL and and/or its isoforms might be involved in the pathophysiology of preeclampsia.