Assessment of oxidative stress parameters in neonatal indirect hyperbilirubinemia treated with phototherapy

Phototherapy is the most commonly used treatment for indirect (unconjugated) hyperbilirubinemia (IHB) in newborns. This study aims to determine the impact of IHB and phototherapy on oxidative stress balance by thiol-disulfide homeostasis and ischemia-modified albümin (IMA). This prospective study included 107 hospitalised newborns with IHB who received phototherapy and 55 controls. Neonates aged 0-28 days with a gestational age above 35 weeks were included in the patient group. Oxidative stress parameters were assessed in the control group as well as before and after phototherapy in the patient group. Sex, gestational age, and birth weight were similar between IHB group and control groups (p > 0.05). Native thiol and total thiol levels were significantly higher in the IHB group compared to controls (p < 0.05). After phototherapy, native thiol, total thiol, and Index 3 values were significantly reduced (p < 0.05), while disulfide levels, disulfide/native thiol ratio, disulfide/total thiol ratio, and IMA values significantly increased (p < 0.05). Oxidative stress via thiol-disulphide homeostasis is increasing in patients hospitalised due to IHB and receiving phototherapy. Our findings suggest that both IHB and phototherapy contribute to oxidative stress imbalance. Phototherapy should be used based on clinical indications and for the minimum needed duration.