Plasma glutathione S-transferase alpha 1-1: a more sensitive marker for hepatocellular damage than serum alanine aminotransferase in hypertensive disorders of pregnancy.

OBJECTIVE

Our purpose was to investigate the value of plasma glutathione S-transferase Alpha 1-1 measurements in the assessment of hepatocellular damage in hypertensive disorders of pregnancy.

STUDY DESIGN

Patients were recruited at the Department of Obstetrics and Gynecology of the University Hospital, Nijmegen, The Netherlands. Five groups of patients were studied: normotensive pregnancy (n = 87), pregnancy-induced hypertension (n = 48), preeclampsia (n = 79), the syndrome of hemolysis, elevated liver enzymes, and low platelets (n = 39), and serially studied normotensive pregnancy (n = 21). Blood was collected for assessment of plasma glutathione S-transferase Alpha 1-1 levels and serum alanine aminotransferase activity. Levels in hypertensive pregnancies were compared with levels in normotensive pregnancy by the Mann-Whitney U test. Patients were categorized according as to whether their values are below (normal) or above (elevated) the upper normal reference level. The difference in relative magnitude of elevation between the two factors was determined by the Wilcoxon matched-pairs signed-rank test.

RESULTS

Plasma levels in the longitudinally studied normotensive pregnancy group did not differ between gestational ages and were not significantly different from those of the normotensive control group. Median levels of glutathione S-transferase Alpha 1-1 and alanine aminotransferase were significantly increased (p < 0.01, p < 0.0001, respectively) in all subgroups of hypertensive pregnancies compared with normotensive pregnancies. When both levels were elevated, the relative magnitude of the increase of glutathione S-transferase Alpha 1-1 levels was significantly higher than that of alanine aminotransferase activity in preeclampsia (p < 0.01) and the syndrome of hemolysis, elevated liver enzymes, and low platelets (p < 0.0001). Almost half the patients with preeclampsia showed elevated levels of alanine aminotransferase and/or glutathione S-transferase Alpha 1-1.

CONCLUSION

Plasma glutathione S-transferase Alpha 1-1 measurements may provide a more sensitive indicator of acute hepatic damage in preeclampsia and the syndrome of hemolysis, elevated liver enzymes, and low platelets compared with the assessment of aminotransferase activity and therefore may allow earlier recognition of these syndromes. The clinical benefits of plasma measurements of glutathione S-transferase Alpha 1-1 for monitoring the hepatic condition in the management of these patients need to be elucidated in further studies.