The paper focuses on questions of etiotropic, pa diarrhea in children. The recommendations are given with the basic principles of evidence-based medicine including summary data from randomized clinical trials and metaanalyses. The new lines of the treatment are discussed such
as the possibility of application of antiemetic, antidiarrheal, antisecretory, probiotic drugs in pediatric practice.

Changes of apoptosis in liver cells are observed in patients with lesions of various etiologies. The aim of this study was a comparative evaluation of the expression of the antiapoptotic factor bcl-2 in liver at CHC and autoimmune liver diseases (AiLD). Immunohistochemical assessment of bcl -2 expression in biliary epithelial cells and non-parenchymal cells were performed in liver biopsies from 33 patients with liver disease (7 – with autoimmune hepatitis (AIH), 10 – with primary biliary cirrhosis (PBC), 6 – overlap syndrome AIH / PBC and 10 – with chronic hepatitis (CHC)). In all groups, the greatest density of bcl-2+ non-parenchymal cells showed in the portal area, moreover, the expression of bcl-2 in non-parenchymal cells at CHC patients was significantly lower than in the other groups. The interrelation between necroinflammatory activity and bcl-2 expression in non-parenchymal liver cells was found (r = 0,35), the relationship with the stage of fibrosis was not found. We were obtained statistically significant differences in bcl-2 expression in biliary epithelial cells by semi-quantitative assessment: in the majority of patients with PBC bcl-2 was expressed over 2/3 of cholangiocytes, at AIH and AIH/PBC patients bcl-2+ reaction was observed in 1/3–2/3 biliary cells, and all CHC patients had bcl-2 expression less than in 1/3 cholangiocytes (p <0.05). Differences between AIH and AIH/PBC of bcl-2 expression in cholangiocytes were not observed. The intensity of bcl-2 expression in biliary epithelial cells can be used as a differential diagnostic marker when necessary to differentiate AIH and CHC in controversial situations and, most importantly, AIH / PBC and PBC.

The results of laboratory and imaging studies 128 patients with a diagnosis of early childhood rotavirus infection. Mono-rotavirus infection in 55,3% of cases proceeded with symptoms of gastroenteritis, severe dehydration accompanied by varying degrees of severity. Mixed-rotavirus infection in 53,5% of cases proceeded with a syndrome characterized by severe enteritis and toxic syndrome. In severe forms of rotavirus infection marked by dysfunction of the liver, pancreas, and the characteristic changes in biochemical and clinical parameters.

The article presents the results of the research of improvement one of possible methods of early diagnostics of viral hepatitis C at first-year old children, who born from mothers with chronic viral hepatitis C, in blood anti-HCV IgG are revealed, based on the study of maintenance of blood serum interleukins in dynamic observation of children. Proven that for children with maternal antibodies to virus of hepatitis C gradual decrease of titer of anti-HCV IgG is marked on background of physiological maintenance of interleukins or their level doesn’t exceed the normal in 1,5-2 time. For children with own antibodies of anti-HCV IgG a few months prior to viral RNA and synthesis of anti-HCV IgМ in blood is observed increase of level of interleukins, especially ІL-6. At children with their own anti-HCV IgG antibodies for few months before the synthesis of anti-HCV IgM are increased levels of interleukins, particularly IL-6. Thus, the serum interleukins response is an important criterion in determining the conditioning of antibodies to virus hepatitis C and earlier diagnosis of viral hepatitis C for first-year old children. Among all interleukins the most specific early marker of viral hepatitis C is IL-6. To clarify the belonging antibodies and more early diagnostics viral hepatitis С to all first-year old children, who born from mothers with chronic viral hepatitis С, and whose blood had educed antibodies of anti-HCV IgG, it is recommended the more careful monitoring of titer of antibodies of class IgМ, IgG, PCR and level of interleukins in serum (especially ІL- 6).

Research of prevalence of a polymorphic marker of a gene of the factor of a necrosis of tumors-α G-308A at 201 children is carried out at the uncomplicated and complicated current of influenza A H1N1pdm09. It is established, that frequency of prevalence of genotypes G/G and G/A at children with not serious forms of influenza A H1N1pdm09 and at a seasonal influenza corresponds population. In case of development of a pneumonia in children at influenza A H1N1pdm09, irrespective of gravity of its current, and also at a serious current of a bacterial pneumonia, distribution of genotypes G/G and G/A differed from healthy population of children. It is revealed, that an allele A polymorphism G-308A of a gene of the factor of a necrosis of tumors-α associations with development of the serious and complicated current of influenza A H1N1pdm09.

First in Russia prospective non-interventional hospital-based study on Streptococcus pneumoniae serotypes causing meningitis and acute otitis media (AOM) in children and community-acquired pneumonia (CAP) in children and adults, as well as serotype coverage by pneumococcal conjugate vaccines (PCV’s) of different composition has been conducted. Serotypes 19F, 14 and serogroup 6 are the leading in meningitis; serotype coverage is 70,6% for PCV7, and 76,5% – for PCV10 and PCV13. Among S. pneumoniae serotypes causing AOM 19F, 3, 23F and serogroup 6 have been the most prevalent in Saint Petersburg. PCV7 and PCV10 provide equal serotypes coverage in AOM – 63,2% among children 0–2 years old, and 32,5% among children 5–17 years old. PCV13 covers up to 79% of serotypes in infants. In CAP PCV7 and PCV10 provide 57,1% serotype coverage in children and 56,1% – in adults. Serotype coverage in CAP for PCV13 has been 14,3% and 34,5% higher for children and adults, correspondingly. Obtained data supports PCV inclusion in children immunization program in Saint Petersburg, whereas PCV13 provides the broadest serotype coverage. In the course PCV’s implementation continued pneumococcal infection surveillance is advisable.

The results are presented of the experimental study of survival rates of autologous bifidobacteria and lactobacilli strains (autostrains) in the intestines of conventional white mice and guinea pigs, as well as an assessment of the effectiveness of the use of isolated bifidobacteria and lactobacilli autostrains in the correction of microecological disorders in the intestines of animals with antibiotic-associated dysbacteriosis. Bifidobacteria and lactobacilli autostrains isolated from intestinal contents of conventional white mice and guinea pigs, as well as rifampicin-resistant derivatives of isolated bacterial autostrains were used in the experiments. It is found that rifampicin-resistant derivatives of bifidobacteria and lactobacilli autostrains retain species and genetically fixed sign of antibiotic resistance. Administered orally to experimental animals, autostrains of bifidobacteria and lactobacilli do not survive in the intestines of animals and are eliminated to 4 days after cessation of administration. Bifidobacteria and lactobacilli autostrains exert virtually no influence on the recovery of the intestinal microbiota in experimental animals with antibiotic-associated dysbacteriosis unlike lactobacilli metabolites and prebiotic Stimbifid, efficiently restoring intestinal microbiota in a short time

Acute intestinal infections remain a significant problem for the majority of economically developed countries. Acute intestinal infection disease incidence in the structure of infectious pathology steadily ranks the 2nd place after acute virus respiratory infections. The urgency of the acute intestinal infections problem is connected with the frequent occurrence of clusters of cases ( outbreaks ) .The last mass and the largest in the last 20 years outbreak of acute intestinal infection , was detected in St. Petersburg in 2013. The Russian Federation takes one of the first places in the world in the number of migrants. The usage of food , stored or cooked with violation of sanitary rules contributes to infection and a high prevalence of intestinal infections among migrants. In the process of medical care when analysing the outbreak among migrants a number of requirements and problems was revealed; solving these problems will make it possible to stop similar epidemic situations during the shortest period and at the lowest cost.

Comparative dynamic clinical and immunomorphological researches of children’s cerebrospinal fluid were made during bacterial purulent meningitis (caused by Neisseria meningitis, Streptococcus pneumoniae, Haemophilus influenza). Regularities connected with presence of CD3 lymphocytes were discovered. They depended on etiology and phase of disease. Children with meningococcal meningitis, pneumococcal meningitis or hemophilic meningitis had different levels of CD3 lymphocytes in cerebrospinal fluid while different phases of disease.

In the article presents the stages of development of epidemiology, given their brief characteristics . We discuss the key issues related to the definition of the object, the subject area and methods of epidemiology at every stage. The definition of the characteristics and epidemiological approaches to the study of human diseases is given. We consider the structure and content of modern epidemiology as a basic medical science related to the field of preventive medicine, and the subject area which includes all of the pathology of the individual – and the infectious and non-infectious. The paradigm of modern epidemiology examined from theoretical, practical and educational positions. Emphasizes the importance of clinical epidemiology and evidence-based medicine in addressing the problems of medicine at the organism and population levels