THE ROLE OF OXIDATIVE STRESS IN THE NECROTIZING ENTEROCOLITIS OF PRETERM

Introduction: Oxidative stress (OS) is strongly envolved in the pathogenesis of many preterm newborn diseases; this is due to the low efficiency of natural antioxidant systems unable to counteract the harmful effects of free radicals (FRs). Necrotizing Enterocolitis (NEC) is a multifactorial disease and it is part of the so called free radicals related diseases. Hypoxic-ischaemic events and inflammation, involved in NEC pathogenesis, are responsible of the overproduction of free radicals (FRs), generating OS. Aim: To test the hypotesis that OS marker levels in cord blood may predict the onset of NEC in high risk infants. Materials and methods: 91 preterm newborns of gestational age between 24 and 33 weeks and birth weight between 460 and 2540 grams were consecutively recruited in two italian neonatal intensive care units. Markers of potential oxidative stress risk, Non Protein Bound Iron (NPBI), and free radicals damage, Advanced Oxidation Protein Products (AOPP) and Total Hydroperoxide (TH), were measured in the cord blood. Associations between NEC and OS markers have been checked through inferential analysis (univariate logistic regression). Results: Out of 91 preterm babies, 8 developed NEC. Babies with NEC had a birth weight (BW) and a gestational age (GA) significantly lower than healthy babies (BW=1100,52 ± 444,30 vs 1320,53 ± 462,09; GA=29,02 ± 2,09 vs 30,14 ± 2,33, respec- tively. p<0.005). Cord blood levels of TH and NPBI were higher in babies with NEC than in babies without, but not significantly. AOPP cord blood levels were significantly higher in babies with NEC than the babies without (AOPP=29,15 ± 20,02 vs 16,72 ± 7,34; p<0.05). AOPP demonstrated a significant value for the identification of the risk of NEC (OR=1.13, CI 95%= 1.001-1.282). Conclusions: OS is strongly associated with NEC. The determination of biochemical OS markers in cord blood can be useful in identifying babies at high risk to develop NEC and in devising new strategies to bring consistent benefits to premature babies.