Ischemia-modified albumin levels in cord blood: A case-control study in uncomplicated and complicated deliveries

Abstract

Background In the past few years ischemia modified albumin (IMA) has emerged as a new biomarker of ischemia in the area of monitoring acute coronary syndromes. We hypothesized that reduced blood flow, such as that resulting from vascular compression in complicated labors or placental ischemia, may increase IMA. IMA level in cord blood could then serve as an indicator of fetal hypoxia and fetal tissue ischemia and serve as a biomarker of the severity of these conditions. Methods We performed a case-control study with 26 newborns (12 normal term deliveries, Apgar 8–9; and 14 complicated labors or pre-term deliveries, Apgar 5–8). Complications were: prematurity (3), fetal distress (6), premature rupture of membranes (6), intrauterine growth retardation (3), pre-eclampsia (1). We also studied 30 healthy adults. IMA was measured in serum from cord blood (or venous blood for adults) by the decrease in cobalt 2+ binding. Results IMA levels in neonates from non-complicated deliveries are significantly higher (45%, p < 0.005) than those of an adult control population, suggesting that IMA may increase as a consequence of labor. This increased IMA in neonates could not be accounted for by the changes in albumin concentration. It is conceivable that a transient increase in IMA reflects, in part, transient localized tissue ischemia due to the external forces exerted on the fetus during the mechanism of labor. IMA levels in cord blood from neonates from complicated deliveries are 50% higher than in neonates from uneventful deliveries ( p < 0.05) while their albumin values are not significantly different (32 ± 3 vs. 33 ± 2 g/l). Moreover, IMA seems to be responsive to hypoxic fetal distress, showing values more than 300% higher in cases of severe fetal hypoxia (Apgar 5 n = 2: 2.19 ± 0.01 AU vs. 0.64 ± 0.24 for controls). IMA values did not correlate significantly with either lipoperoxides or CRP levels. Conclusions This is the initial reporting of IMA levels in cord blood from normal deliveries compared to healthy adult ranges and neonates from complicated deliveries. Cord blood IMA levels may be an indicator of fetal ischemia and/or hypoxia. This test could become an additional biomarker to be used in conjunction with other markers and/or clinical scores aimed at determining risk of neurological complications of fetal distress.