Hormone therapy affecting interferon defense in children with infectious mononucleosis

23 children diagnosed with acute infectious mononucleosis were hospitalized and examined after a short prednisolone treatment course. Related interferon status during infection was compared with that in 38 patients with acute infectious mononucleosis receiving no hormone therapy. Interferon status was investigated by Ershov method, allowing to estimate amount of interferon in the blood serum samples or patient blood cell culture by assessing interferon biological activity. Along with measuring IFNα or IFNγ biological activity, their level was quantified by using enzyme immunoassay. Immunological examination conducted on the next day after the end of hormone therapy revealed sharply decreased potential of patient blood cells to produce both IFNα and IFNγ. The multiplicity of IFNα and IFNγ titer reduction in various patients varied by 4–5 and 3–4-fold, respectively. The concentration of IFNα, determined by ELISA, decreased by 4–6-fold, whereas for IFNγ — by 1.5–2-fold. A follow-up examination 1 month after discharge from the clinic showed that mean IFNα titer in children aged 3–6 years and treated with prednisolone was significantly reduced compared to the baseline, whereas most patients receiving no hormone therapy had normal IFNα production. The change in the level of IFNα 1 month after hormone therapy in 7–14-year age group was similar. IFNγ production quickly recovered, and 1 month after discharge from the clinic, its concentration in culture supernatants from patients reached 10–15 ng/ml, exceeding normal values more than twice. The biological activity of IFNγ in these culture supernatants was significantly higher than those immediately after hormone therapy, whereas in 3–6-year-old group of patients it was also higher than baseline level. These results can serve as a laboratory justification for including recombinant IFNα-2b drugs in the therapy of such patients, presumably immediately after the end of hormone course. Overall, laboratory justified administration of interferon preparations seems to be necessary to determine optimal timepoint for applying such drugs to increase effectiveness for achieving a durable patient recovery