Cirrhosis is the end result of liver fibrosis in chronic liver diseases. Studying the mechanisms of its development and developing measures to slow down and regress it based on this knowledge seem to be important tasks for medicine. Currently, disorders of the gut–liver axis have great importance in the pathogenesis of cirrhosis. However, gut dysbiosis, which manifests as increased proportions in the gut microbiota of Bacilli and Proteobacteria that are capable of bacterial translocation and a decreased proportion of Clostridia that strengthen the intestinal barrier, occurs even at the pre-cirrhotic stage of chronic liver disease. This leads to the development of bacterial translocation, a process by which those microbes enter the blood of the portal vein and then the liver tissue, where they activate Kupffer cells through Toll-like receptor 4. In response, the Kupffer cells produce profibrogenic cytokines, which activate hepatic stellate cells, stimulating their transformation into myofibroblasts that produce collagen and other elements of the extracellular matrix. Blocking bacterial translocation with antibiotics, probiotics, synbiotics, and other methods could slow down the progression of liver fibrosis. This was shown in a number of animal models but requires further verification in long-term randomized controlled trials with humans.

Aim:present clinical guidelines, aimed at general practitioners, gastroenterologists, cardiologists, endocrinologists, comprise up-to-date methods of diagnosis and treatment of non-alcoholic fatty liver disease.Key points.Nonalcoholic fatty liver disease, the most wide-spread chronic liver disease, is characterized by accumulation of fat by more than 5 % of hepatocytes and presented by two histological forms: steatosis and nonalcoholic steatohepatitis. Clinical guidelines provide current views on pathogenesis of nonalcoholic fatty liver disease as a multisystem disease, methods of invasive and noninvasive diagnosis of steatosis and liver fibrosis, principles of nondrug treatment and pharmacotherapy of nonalcoholic fatty liver disease and associated conditions. Complications of nonalcoholic fatty liver disease include aggravation of cardiometabolic risks, development of hepatocellular cancer, progression of liver fibrosis to cirrhotic stage.Conclusion.Progression of liver disease can be avoided, cardiometabolic risks can be reduced and patients' prognosis — improved by the timely recognition of diagnosis of nonalcoholic fatty liver disease and associated comorbidities and competent multidisciplinary management of these patients.

Влияние урсодезоксихолевой кислоты на воспаление, стеатоз и фиброз печени и факторы атерогенеза у больных неалкогольной жировой болезнью печени: результаты исследования УСПЕХ

Aim. The clinical guidelines are intended to provide information support for making decisions by gastroenterologists, general practitioners and internists that will improve the quality of medical care for patients with non-alcoholic fatty liver disease, taking into account the latest clinical data and principles of evidence-based medicine. Key points. Clinical guidelines contain information about current views on etiology, risk factors and pathogenesis of nonalcoholic fatty liver disease, peculiarities of its clinical course. Also given recommendations provide information on current methods of laboratory and instrumental diagnostics, invasive and non-invasive tools for nonalcoholic fatty liver disease and its clinical phenotypes assessment, approaches to its treatment, considering the presence of comorbidities, features of dispensary monitoring and prophylaxis. The information is illustrated with algorithms of differential diagnosis and physician's actions. In addition, there is information for the patient and criteria for assessing the quality of medical care. Conclusion. Awareness of specialists in the issues of diagnosis, treatment and follow-up of patients with nonalcoholic fatty liver disease contributes to the timely diagnosis and initiation of treatment, which in the long term will significantly affect their prognosis and quality of life.

Descriptive statistics provides tools to explore, summarize and illustrate the research data. In this tutorial we discuss two main types of data - qualitative and quantitative variables, and the most common approaches to characterize data distribution numerically and graphically. This article presents two important sets of parameters - measures of the central tendency (mean, median and mode) and variation (standard deviation, quantiles) and suggests the most suitable conditions for their application. We explain the difference between the general population and random samples, that are usually analyzed in studies. The parameters which characterize the sample (for example, measures of the central tendency) are point estimates, that can differ from the respective parameters of the general population. We introduce the concept of confidence interval - the range of values, which likely includes the true value of the parameter for the general population. All concepts and definitions are illustrated with examples, which simulate the research data.

Portal vein thrombosis (PVT) in patients with liver cirrhosis is a common complication associated with adverse outcomes. Aim. To build a predictive model for PVT in cirrhotic patients. Materials and methods. A single centre case-control study was carried out. From the database of 1512 cirrhotic patients 94 with newly diagnosed PVT based on contrast-enhanced computed tomography were referred to the Case group. Malignant PVT was an exclusion criterion. Patients without PVT were stratified and matched according to sex, age and etiology of cirrhosis; case-control ratio was 1 : 3–4. The prevalence of PVT in the database, clinical, laboratory, instrumental parameters of the groups were evaluated. Logistic regression model was used to estimate association between variables and PVT. Results and discussion. The overall prevalence of PVT was 6.2% with the highest rates among the patients with HBV infection – 16.7%, nonalcoholic steatohepatitis – 15.6%, alcohol abuse in combination with HCV infection – 11.7%. The best predictive model included variables: Child-Pugh classes B–C (coefficient of regression β=1.853, р=0.001), ascites (β=0.460, р=0.003), hepatocellular carcinoma without vascular invasion (β=2.126, р=0.0001), endoscopic band ligation (β=0.774, р=0.003), azygoportal disconnection (β=2.734, р=0.001), portal hypertensive gastropathy (β=0.793, р=0.017), portal vein diameter (β=0.203, р=0.004), and local factors – ulcerative colitis flare, Clostridium difficile enterocolitis, spontaneous bacterial peritonitis, colorectal cancer, splenectomy, cholecystectomy (β=2.075, р=0.017). The model had accuracy 85.8% (95% CI 81.7–89.4%), sensitivity – 55.1% (95% CI 43.4–66.4%), specificity – 95% (95% CI 91.6–97.3%), and AUC – 0.871 (95% CI 0.826–0.916). Conclusion. Child-Pugh classes B–C, severe portal hypertension, hepatocellular carcinoma without vascular invasion, and local factors were estimated as risk factors of PVT in cirrhotic patients. Keywords: portal vein thrombosis, liver cirrhosis, case-control study, Child-Pugh class, portal hypertension, hepatocellular carcinoma, local factors, logistic regression model