Comparative and diagnostic evaluation of maternal serum prostasin in early-onset preeclampsia

We aimed to compare maternal serum prostasin levels between women with early-onset preeclampsia (PE) and healthy pregnant controls to establish pathophysiological differences. We also sought to evaluate the diagnostic performance of maternal serum prostasin as a potential biomarker for early-onset PE, including determination of optimal cutoff values for clinical application. This was a prospective case-control study including 43 pregnant women who were diagnosed with early-onset PE between 200/7 to 340/7 weeks of gestation from March to September 2022. Also, 45 healthy pregnant women were included in the control group. Demographic characteristics, complete blood count and biochemical parameters, and serum prostasin concentrations were documented. A receiver operating characteristic curve was generated to demonstrate the sensitivity and specificity of prostasin, and the optimal cutoff value was determined using the Youden index. The median maternal serum prostasin level was found to be significantly higher in the early-onset PE group (31.66 [27.12-51.00] ng/mL) compared to the control group (22.33 [16.03-25.89] ng/mL) with a P-value <.001. The area under the curve was found to be 0.820 ± 0.047 (95% CI: 0.729-0.912), indicating a statistically significant discriminative ability (P < .001). The optimal cutoff value for maternal serum prostasin level was determined using the Youden index, with a threshold of ≥26.44 ng/mL corresponding to a sensitivity of 0.837 and a specificity of 0.778 for the diagnosis of early-onset PE. Based on the multivariate model results, a maternal serum prostasin value of >26.44 ng/mL increases the risk of early-onset PE by approximately 20-fold. Maternal serum prostasin levels are significantly elevated in early-onset preeclamptic mothers compared to the healthy controls. These findings suggest that prostasin may play a role in early-onset PE pathophysiology and could serve as a biomarker for its diagnosis.