The aims of this study were to identify the clinical characteristics and determine the changes in the expression of cytokines and apoptosis-related genes in children with infectious mononucleosis.

Serological examinations of 15 pediatric patients diagnosed with infectious mononucleosis were performed prospectively. Peripheral blood from the patients was used to compare the composition of T cell subsets, cytokines, Epstein-Barr virus (EBV) DNA, and the expression of apoptosis-related genes with those in 10 healthy children.

Mean age of the patient group was 5.7±3.4 (range, 3-9) years, and the male-to-female ratio was 1.5:1. Fever, sore throat, pharyngitis/tonsillitis, and cervical lymph node enlargement were the most common symptoms and signs. The proportions of CD3+ T cells, CD8+ suppressor cells, and CD56+ natural killer (NK) cells were higher in the patient group than in the control group ( P <0.01). The IL-2, IL-6, and interferon (IFN)-γ levels were higher in the early symptomatic period ( P <0.01). Mean amount of EBV DNA in the patients was 10^2.38 copies/µg, and the amount was the highest at the beginning of the symptomatic period and normalized during the convalescent phase. Bcl-2 expression increased during the initial phase, while Bax expression increased during the convalescent phase. Further, FasL expression increased 1 week after symptom presentation and decreased during the convalescent phase. There was no significant change in Fas expression.

We analyzed the clinical characteristics and changes in the expression ofcytokines and apoptosis-related genes in the patients with infectious mononucleosis.