Critical Level of Alanine Transaminase to Predict Foetomaternal Outcome in Intrahepatic Cholestasis of Pregnancy: A Case-control Study

Abstract

Introduction: Intrahepatic Cholestasis of Pregnancy (IHCP) is a disorder of the second and third trimester causing pruritis without a rash in the women. To avoid the adversities, early delivery is indicated before serum bile acids levels of >40 μmol/L is reached. In the settingswhere bile acid testing is not available, serum transaminases can be used for diagnosis and management of IHCP. Aim: To find out value of Alanine Transaminase (ALT) for the prediction of adverse outcomes. Materials and Methods: This case-control study was carried out from October 2018 to March 2020, enrolled 75 singleton women with IHCP and 75 controls in their third trimester. The diagnosis was based on the presence of pruritis without an identifiable dermatological cause along with raised serum transaminases. Serum ALT levels and the foetomaternal outcomes were noted. Statistical analysis was done using Statistical Package for Social Sciences (SPSS) version 21.0. Mann-Whitney test, Chi-square test and Fisher’s exact test were used to compare all variables. The p-value of <0.05 was considered statistically significant. Results: The mean age of women in the IHCP and control groups was 24.81±4.2 and 25.95±5.13 years, respectively and the mean gestational age of women was 34±2.89 weeks. Women with IHCP had increased incidence of induction of labour (p=0.0003) and meconium staining of liquor (p=0.002) as compared to controls. Serum ALT levels showed a significant positive association with meconium staining of liquor (p=0.041), Intrauterine Death (p=0.01), and Neonatal Intensive Care Unit (NICU) admission (p=0.006) in women with IHCP. An ALT value of 133 U/L was found to be predictive of adverse foetal outcomes with sensitivity, specificity and likelihood ratio of 65.7%, 82.5% and 3.76, respectively. Conclusion: IHCP leads to adverse foetal outcomes. But pruritis is the only maternal distress. ALT >133 U/L is predictive of adverse foetal outcome, therefore, termination of pregnancy can be advocated above this level.