Plasma glutathione S-transferase Pi 1-1 measurements in the study of hemolysis in hypertensive disorders of pregnancy

Objective: To investigate the value of plasma glutathione S-transferase Pi 1-1 (GSTP1-1) measurements in the assessment of hemolysis in hypertensive disorders of pregnancy. Methods: Plasma GSTP1-1 and haptoglobin levels and serum lactate dehydrogenase (LDH) activity were measured in 81 healthy nonpregnant female blood donors between 20 and 40 years of age, 41 women during uncomplicated normotensive pregnancy, 35 women with pregnancy-induced hyper tension, 67 women with preeclampsia, and 34 women with the HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome. Levels in hypertensive pregnancies were compared to levels in normotensive pregnancy, and levels in normotensive pregnancy were compared to levels in blood donors by the Mann-Whitney U-test. Results: Median GSTP1-1 and LDH levels were significantly increased (p < 0.01) and haptoglobin significantly decreased (p < 0.01) in preeclampsia and the HELLP syndrome as compared to normotensive pregnancy. Both GSTP1-1 and LDH levels were significantly higher in normotensive pregnant women as compared to nonpregnant women (p < 0.0001). The percentage of preeclamptic patients (26.9%) or patients with the HELLP syndrome (73.5%) with elevated GSTP1-1 levels was lower than those with elevated LDH (38.8% and 100%, respectively) or decreased haptoglobin levels (41.8% and 97%, respectively). Conclusions: We conclude that plasma GSTP1-1 levels may provide useful information on hemolysis in hypertensive disorders of pregnancy in addition to serum LDH activity and plasma haptoglobin levels and that the degree of hemolysis in hypertensive disorders of pregnancy, especially in the HELLP syndrome, is probably less prominent than generally assumed.