Abstract: Objective To explore and analysis the efficacy of placental peptides in the treatment of secondary neutropenia in children with Epstein-Barr virus infection and their impact on immune function. Method From April 2022 to July 2023, 81 cases of EB virus infection combined with secondary neutropenia diagnosed and treated at Guizhou Provincial People's Hospital were selected as the research subjects. Accorded to the random number table method, 81 children were divided into the placental peptide group of 41 cases and the control group of 40 cases. The control group were received routine medication treatment, while the placental peptide group were received placental peptide treatment on the basis of the control group. Both groups were treated and observed for 14 days to determine the treatment effect and immune function changes of the children. Result The total effective rates of the placental peptide group after 14 days of treatment were 97.56%, while the control group were 82.50%. The placental peptide group showed a significant improvement compared to the control group (P<0.05). The disappearance time of clinical symptoms such as liver and spleen enlargement, fever, pharyngitis, and lymph node enlargement in the placental peptide group were significantly reduced compared to the control group (P<0.05). After 14 days of treatment, the relative proportion of CD4⁺T lymphocytes and CD8⁺T lymphocytes in both groups were significantly higher than before treatment, and the placental peptide group were also higher than those in the control group (P<0.05). The incidence of adverse reactions such as nausea, vomiting and diarrhea during the 14 day treatment period in the placental peptide group were lower(14.63% vs 17.50%), compared with the control group. There were no significant difference between the placental peptide group and the control group (P>0.05). Conclusion The treatment of Epstein-Barr virus infection in children with secondary neutropenia with placental peptides can improve the therapeutic effect, promote the relief of clinical symptoms, improve immune function, and do not increase the occurrence of adverse reactions.

Key words: placental peptides, pediatric EB virus, secondary neutropenia, immune function, adverse reactions