Clinical symptoms of escherichiosis as well as duration depend on present background infection. In the majority of children (109-87.9 %), high body temperature was registered at the hospital, but in patients with EBVI, the indices were significantly higher compared to mono-infection. In patients with EBVI greater number of episodes of the hyperemia of the oropharynx, signs of coriza, the increase of regional cervical and submandibular lymph nodes, enlargement of the liver were recorded. It was revealed a longer preservation of fever, disturbed general condition, intestinal dysfunction, signs of hepatomegaly, longer hospitalization period in patients with mixed infection compared to mono-infection. In patients with mono-infection determined higher figures for the content of peripheral blood leukocytes; segmental neutrophils; ESR. In patients with mixed infection, the indices of hemoglobin were lower, which differed significantly not only from the control group, but also from the mono-infection group. In patients with mixed infection the increased echogenicity of liver parenchyma was more frequent, as compared to patients with mono-infection, as well as mesadenitis and lymphadenitis in the liver The maximum increase in the phagocytic activity of neutrophils in the acute period of escherichiosis occurs in patients with mono-infection and with active EBVI (p < 0.01) and is characterized by a high functional reserve of bactericidal neutrophils. In children with latent EBVI, escherichiosis is accompanied by a less significant (p < 0.05) increase in phagocytic activity of neutrophils and a decrease in the functional reserve of the oxygen dependent mechanism of bactericidality of neutrophils (p ˂ 0.05). By the recovery period, full normalization of phagocytic activity of neutrophils occurs only in patients with monoinfection, p ≥ 0.05. In the acute period of escherichiosis mixed infection (regardless of the activity of EBVI) is accompanied by more pronounced cytokine reactivity of patients (p < 0.05) compared with mono-infection (p > 0.05). We did not find a significant difference in the levels of anti-inflammatory IL-4 in different stages of escherichiosis in children with latent EBVI (p > 0.05), whereas in patients with mono-infection and esherichiosis with active EBVI, elevation of IL-4 to the period of convalescence was probable (p ˂ 0.001). In the acute period of escherichiosis, in all patients signs of inhibition of the cellular immune response with decreased number of CD3+, CD4+ and CD8+ lymphocytes with a maximum deviation of CD3+ and CD4+ parameters in patients with mixed infection (p ˂ 0.01) were detected. The maximum increase in CD19+ was registered in mono-infection as compared with the control group (p ˂ 0.001), and with mixed infection, (p ˂ 0.05). The probable increase in the CD21+ content in patients with escherichiosis was detected only with the presence of a concomitant EBVI with the maximum in patients with active form of EBVI (p ˂ 0.01). In the period of convalescence of escherichiosis in patients with mixed infection, the state of immunosuppression (p < 0.01) was maintained, which was most expressive in latent form of EBVI (p < 0.001). Escherichiosis in young children was accompanied by an increase in the serum IgM, IgA and IgG levels in the dynamics of the disease, with the most significant increase of IgG levels in latent EBVI (p < 0.10). Comprehensive evaluation of the degree of deviation of levels of blood immunoglobulins in the period of convalescence revealed the maximum expressive oscillations in mixed infection (p < 0.001) as compared to mono-infection (p ˂ 0.01). Mathematical analysis was performed to determine the pathogenetic role of the indicators and their hierarchical significance. The criteria of the unfavorable course of escherichiosis in young children were determined. The diagnostic algorithm for the presence of EBVI in young children with escherichiosis, and prediction of the course of intestinal infection were developed. Abridged diagnostic algorithm was proposed without taking into account immune parameters, which, by accuracy (87.10 %), did not yield to the extended full algorithm.
The results of the study allowed to theoretical substation of the ways of improving the treatment of children with escherichiosis and different EBVI activity.
