van Zoeren-Grobben D, Jacobs N J, Houdkamp E, Lindeman J H, Drejer D F, Berger H M
Department of Pediatrics, University Hospital Leiden, The Netherlands.
J Pediatr Gastroenterol Nutr. 1998 Jan;26(1):73-9. doi: 10.1097/00005176-199801000-00013.
Vitamin E is an essential component of the antioxidant defenses, but supplementation can have side effects in the preterm infant. Careful monitoring of vitamin E status is thus essential, however no consensus has been reached on the best clinical method.
In 47 healthy preterm infants, several methods for assessment of vitamin E status were evaluated: plasma and erythrocyte vitamin E levels were measured, vitamin E lipid ratios were calculated, and two variations of the hydrogen peroxide hemolysis test were conducted.
At birth, the plasma and erythrocyte vitamin E levels were low. After birth, the plasma levels rose gradually, whereas the erythrocyte levels remained low. In contrast, the vitamin E-total-lipid ratio was in the low normal range from birth onwards. Vitamin E-lipid ratios using two lipid components (cholesterol with triglycerides, or cholesterol with phospholipids) or one lipid component (cholesterol) correlated with the vitamin E-total-lipid ratio with a good sensitivity and specificity. The susceptibility of erythrocytes to hydrogen peroxide-induced damage (measured as potassium release or malondialdehyde production) was high at birth and declined after birth. However, this susceptibility did not correlate with plasma or erythrocyte vitamin E levels or vitamin E-total-lipid ratio, and the hydrogen peroxide hemolysis test is not a reliable indicator of vitamin E status in preterm infants.
Our study indicated that a gold standard for clinical assessment of vitamin E status in preterm infants is yet to be found.
维生素E是抗氧化防御系统的重要组成部分，但补充维生素E可能对早产儿产生副作用。因此，仔细监测维生素E状态至关重要，然而，对于最佳临床方法尚未达成共识。
对47名健康早产儿评估了几种维生素E状态评估方法：测量血浆和红细胞维生素E水平，计算维生素E与脂质的比率，并进行了两种过氧化氢溶血试验的变体。
出生时，血浆和红细胞维生素E水平较低。出生后，血浆水平逐渐上升，而红细胞水平仍较低。相比之下，维生素E与总脂质的比率从出生起就处于低正常范围。使用两种脂质成分（胆固醇与甘油三酯，或胆固醇与磷脂）或一种脂质成分（胆固醇）的维生素E与脂质的比率与维生素E与总脂质的比率具有良好的敏感性和特异性相关性。红细胞对过氧化氢诱导损伤的敏感性（以钾释放或丙二醛产生来衡量）在出生时较高，出生后下降。然而，这种敏感性与血浆或红细胞维生素E水平或维生素E与总脂质的比率无关，过氧化氢溶血试验不是早产儿维生素E状态的可靠指标。
我们的研究表明，尚未找到临床评估早产儿维生素E状态的金标准。
