Evaluation of liver enzymes in asymptomatic chronic hepatitis B virus infected pregnant women
Background The major risk factor for perinatal transmission of hepatitis B virus (HBV) infection and/or immunoprophylaxis failure is the level of maternal HBV-DNA. The aim of this study was to evaluate commonly used laboratory parameters in HBeAg-negative chronic HBVinfected pregnant women and to correlate the findings with the presence or absence of viremia.
Methods 166 consecutive chronic HBV-infected pregnant women were hematologically, serologically and virologically evaluated between the 28th and 32nd week of gestation. 101 women were finally evaluated (66 HBV-DNA positive and 35 HBV-DNA negative). Twenty-one women exhibited HBV-DNA levels above 2000 IU/mL.
Results Viremic women exhibit significantly higher ALT (25.43 IU/L vs. 15.50 IU/L, P=0.016) and GGT (17.47 IU/L vs. 10.22 IU/L, P=0.001) values as well as significantly lower white blood cell (10527 vs. 13793, P=0.008) and neutrophil count (7776 vs. 11088, P=0.001), compared to non-viremic women. The optimal cut-off points discriminating those women with a high probability to have detectable serum HBV-DNA were 7 IU/L for GGT (sensitivity = 81.6%, specificity = 69.6%, area under the ROC curve (AUC) = 75.3%) and 12 IU/L for ALT (sensitivity = 74.1%, specificity = 56.2%, AUC = 65.4%). The positive predictive value of detectable HBV-DNA in women with both serum parameters above the new limits proposed was 88.8% whereas the negative predictive value was 75%.
Conclusion Presence of HBV-DNA in maternal blood during the third trimester of pregnancy is significantly associated with maternal serum GGT levels. Women with GGT above 7 IU/L and ALT above 12 IU/L have a higher probability of HBV-DNA presence in maternal blood.
Keywords Hepatitis B, HBV-DNA, ALT, GGT, hemodilution, pregnancy