Effect of phototherapy on B and T lymphocytes in Egyptian infants suffering from neonatal jaundice

Background: Neonatal jaundice is one of the most common problems that affect newborn infants, and phototherapy is usually used for treatment. Objectives: Evaluation of the effect of phototherapy on neonatal immune system through measuring the percentage of B and T lymphocytes and determining the frequency of development of infections and need for hospitalisation during the first six months of life. Methods: A prospective cohort study was conducted on 50 full term new-borns; 25 with indirect hyperbilirubinaemia and treated with conventional phototherapy and 25 healthy matched neonates as untreated controls. The percentages of CD19+, CD4+ and CD8+ lymphocytes were measured by flow cytometry before phototherapy and 72 h after exposure. Follow-up of the study group for the occurrence of infections for a period of six months after phototherapy. Results: The study showed a significant difference in CD19+ lymphocytes percentage between patients before phototherapy and controls (P value < 0.01), also a significant correlation between serum levels of total bilirubin in patients and CD19+ lymphocytes percentage (P value < 0.05). There was no significant difference between the percentages of CD19+, CD4+ and CD8+ lymphocytes in patients before or after 72 h of exposure to phototherapy (P value > 0.05). Also, there was no correlation between the percentages of CD19+, CD4+ and CD8+ lymphocytes after 72 h of exposure to phototherapy and the occurrence of infections (Gastrointestinal tract and Respiratory tract infection) after six months of follow-up (P value > 0.05). More studies are needed with larger number of patients to determine the effect of phototherapy on immune system. (C) 2016 SEICAP. Published by Elsevier Espana, S.L.U. All rights reserved.