It was determined earlier (G.P. Ivanova, 2012) that a chronic course of leukoencephalitis in teenagers caused by inadequate response of cytokine system to the combination of two herpesviruses (HV) — EBV and HHV-6, leads to the development of multiple sclerosis (MS) in 44% of cases. The research objective was to characterize the cytokine response in children with MS with simultaneous screening of the presence of active HV infections. 39 children with the diagnosis “MS” were under observation, 34 of them had relapsing-remitting (RR) MS, and 5 children had a progressing course of MS (PMS). Concentration of cytokines IL-1 β , IL-6, IL-8, IL-10, IFN α , IFN γ , and IL-4 was identified in blood serum and cerebrospinal liquid (CSF) by enzyme-linked immunosorbent assay, HV DNA was revealed by PCR. Cytokine status in children with MS had some differences depending on the phase of the disease, clinical severity of the relapse and the course of MS. The relapse phase of RRMS was associated with the accumulation of IL-8, IL-10, and IL-6 in the blood, and index IFN γ /IL-4 modulations in accordance with the clinical severity of the relapse. A severe aggravation of the disease in children with PMS was accompanied by the increase of IL-8 system response. HV DNA was revealed in 27 patients from 39 ones (69%) in blood and in 17 patients (44%) in CSF with the predominance of EBV (93%), frequently in combination with HHV-6. During an acute period the frequency of HV DNA identification increased 2–3 times to compare with the remission period. Unlike children with RRMS, a mixed-infection of 3–4 herpes viruses was revealed in all 5 patients with PMS. According to the results summary it is possible to make a conclusion that HV-infection has an important role in MS pathogenesis in teenagers, taking part in the aggravation and progression of the disease by its effect on the cytokine system response. EBV-infection dominates among HV, however the risk of MS development increases to a great extent in the case of EBV association with another lymphotropic virus — HHV-6.

There was conducted a survey among 65 children aged from 1 year to 17 with varicella encephalitis. There was determined predominance of cerebellar forms of the disease, in 93,9%, that is characterized by the development of the light pyramidal disorders on the contrast to the cerebral that is characterized by the development of convulsivecomatose syndrome. It was determined that the disease is distinguished by the rareness of the detected changes on the MRI, 12,3% only. It was detected that the changes of the evoked potentials could be seen among all the patients and are characterized by the predominance demyelinating changes of the brainstem structures when having a cerebellar form and neuronal disorders of the cerebral hemisphere when having a cerebral form. The outcome of the cerebellar form is recovery in 100% of cases, and in cerebral – the development of epilepsy was detected in 50% and death in 25%.