Maternal Urinary Carbohydrate Antigen 19-9 as a Novel Biomarker for Evaluating Fetal Hydronephrosis: A Pilot Study

Abstract

To evaluate maternal urinary CA19-9 as a potential marker to diagnose severe antenatal hydronephrosis (ANH) during pregnancy and to compare the values with those in normal pregnancies as controls. A total of 20 women in their third pregnancy trimester were enrolled. An anteroposterior pelvic diameter (APD) of ≥15 was considered as severe ANH. Case group consisted of 10 women with a diagnosis of severe ANH. Ten women with similar age, gestational age, fetal sex, normal ultrasonography, and no history of any congenital anomalies were chosen as controls. Urine samples were collected and maternal urinary CA19-9 was measured. The levels in case and control groups were compared using Mann-Whitney U test. Each group consisted of nine mothers with male fetuses and one with female fetus. The APD in the ANH group ranged from 17 to 40 mm. Five of 10 children in the ANH group also had contralateral APD of ≥4 mm (bilateral ANH). The mean age and gestational age of pregnant women in the two groups were comparable. The mean maternal CA19-9 was significantly higher in the ANH group compared with the controls (mean: 134.5 U/mL vs 22.2 U/mL, P < .001). To our best knowledge, this is the first time that maternal urinary CA19-9 has been used as a marker for ANH. Based on these pilot data, CA19-9 levels are significantly higher in the urine of pregnant women carrying fetuses with severe ANH, and it may have the potential to serve as a noninvasive and useful biomarker to diagnose ANH.