Intensive phototherapy and oxidant-antioxidant status in infants with jaundice

Conventional phototherapy converts unconjugated bilirubin to its oxidation products and consequently causes oxidative stress with lipid peroxidation products. New devices that deliver intensive phototherapy are efficacious in treating severe hyperbilirubinemia and minimizing the need for exchange transfusions. However, the oxidative stress status when using these devices has not been explored. Therefore, we aimed to study the impact of using intensive phototherapy on the oxidant-antioxidant status in severely jaundiced neonates.

This prospective case-control study included term newborns admitted with severe hyperbilirubinemia managed with intensive phototherapy. Baseline oxidant-antioxidant concentrations were compared to healthy controls and re-measured after 8 h of intensive phototherapy exposure.

The study included 40 cases with severe jaundice and 40 non-jaundiced apparently normal controls. Total serum bilirubin at enrollment was 23.4 ± 4.2 mg/dl that significantly decreased after 8 h of therapy to 15.4 ± 3.4 mg/dl (p < 0.001). The decline of total serum bilirubin was 1 mg/dl/h. Bilirubin: albumin ratio decreased from 3.45 ± 0.28 to 2.7 ± 0.21 (p < 0.001). Total antioxidant capacity (TAC), superoxide dismutase (SOD), malondialdehyde (MDA), and total oxidative stress (TOS) concentrations were lower in cases (p < 0.001, p < 0.001, p = 0.049, and p < 0.001 respectively) compared to controls. Following 8 h of intensive phototherapy, further decline of TAC (p = 0.016) with increased concentrations of TOS (p = 0.005) were noted. SOD and MDA did not change.

Although efficacious, intensive phototherapy was associated with increased oxidative stress. The clinical correlates for harms related to such oxidative stress need further studying.