Serum autotaxin levels correlate with the severity of pruritus in intrahepatic cholestasis of pregnancy

Abstract

Purpose This study aimed to examine autotaxin (ATX) concentrations in the serum of pregnant women complicated with intrahepatic cholestasis of pregnancy (ICP) and compare them with individuals with uncomplicated healthy pregnancies. Methods This prospective case–control study took place with 83 pregnant women. The study group included 43 pregnant women presenting with a singleton pregnancy diagnosed with ICP in their third trimester of pregnancy. The diagnostic power of the ATX variable was examined by receiver operating characteristic analysis, and the cut‐off value calculated according to the Youden index was summarized with the related sensitivity and specificity points. Results The mean serum concentration of maternal ATX was significantly higher in the ICP cases (8.91 ± 2.69 pg/mL) compared to the pregnant women in the control group (3.59 ± 1.39 ng/mL, p < 0.001). According to the Youden index, a 5.80 ng/mL cut‐off value of serum ATX concentrations can be used to diagnose ICP with 97.7% sensitivity and 97.5% specificity. A significant highly positive correlation was found between maternal serum ATX levels and maternal serum total bile acid levels (r = 0.633 and p < 0.001) and itch intensity, which was objectified by the visual analog scale score (r = 0.951 and p < 0.001). Conclusion Maternal serum ATX levels were significantly increased in ICP patients as compared with healthy pregnant women. Also, serum ATX activity was highly correlated with the itch intensity. We consider that ATX might represent a robust, accurate, and reliable circulating biomarker to diagnose ICP.