Aim. The study reviews current evidence on digestive system lesions provoked by the new COVID-19 coronavirus infection.

Key points. Alongside the destructive impact on respiratory system, COVID-19 manifests itself in gastrointestinal symptoms (nausea, vomiting, diarrhoea) that may precede respiratory signs and prevail in the clinical picture of infection. Patients with chronic inflammatory bowel diseases receiving immunosuppressive therapy are at elevated risk of severe COVID-19 progression. The new coronavirus infection may induce liver damage with increased transaminase activity.

Conclusion. Association of digestive system lesions with COVID-19 remains understudied and requires further research.

Aim. Description of risk factors, pathogenesis and treatment strategies of gastrointestinal bleeding (GIB) in the course of antithrombotic therapy in patients with coronary heart disease (CHD).

Key points. Risk factors of GIB during antithrombotic therapy in CHD patients include: GIB, gastric and/or duodenal ulcer in the history, reflux esophagitis, presence of H. pylori, inflammatory bowel disease, diverticula, haemorrhoids, angiodysplasia, gastrointestinal neoplasia, age above 65 years, concomitant treatment with non-steroidal anti-inflammatory drugs (NSAIDs), glomerular filtration rate <50 mL/min, high doses of direct oral anticoagulants (DOACs) ≥3 in HAS-BLED score. Pathogenesis of GIB in the course of antithrombotic therapy is associated with systemic hypocoagulation and local damaging effects of these drugs. Strategies of GIB treatment during DOAC therapy in patients with CHD are determined by severity of bleeding and threat to life. Aside to standard conservative measures, endoscopic or surgical haemostasis requires usage of antidotes to suppress effects of DOACs and other specific drugs in severe cases.

Conclusion. GIB associated with antithrombotic therapy in CHD patients poses a serious medical problem of growing importance with wider application of anticoagulant drugs. Antithrombotic therapy requires accurate decision making, risk assessment, careful monitoring of the patient’s condition and timely diagnosis of gastrointestinal disorders following good rationale in GIB prevention.

Aim of review. The review highlights modern concepts of the role of microbiome in sustaining the human body, the place of probiotics in treatment and prevention of pathologies related to disorders in healthy microbiota.

Key points. Microbiome is a unique panorganismal system normally maintaining self-equilibrium and possessing a vast and diverse functionality. Imbalance in normal microbiota can be assisted by probiotics, i.e. living microorganisms that sustain health of the host when being supplied in adequate amounts. Alike normal microflora, probiotic strains incorporate into general metabolism by mediating a spectrum of functions, e.g. maintaining colonisation resistance, nutrient metabolism, supplying the host with vital metabolites, regulation of local and adaptive immune responses, enhancing the intestinal barrier. Probiotics are applied in various diseases associated with general imbalances of the organism. Modern probiotic preparations are characterised by acid- and antibiotic-resistivity and safety, thus being suitable for treating gut microbiome-associated disorders in various age groups.

Conclusion. Probiotic strains, as well as medications designed on their basis, are widely applied and show good promise. Further research into their properties will advance the prospects of probiotic treatment.

Aim. Assessment of the quality of life and physical activity level in students with and without symptoms of functional dyspepsia (FD) and irritable bowel syndrome (IBS) according to questionnaire “7×7” (7 symptoms per 7 days).

Materials and methods. Symptoms of FD and IBS were surveyed using the “7×7” questionnaire. Level of physical activity was evaluated according to the short IPAQ, and quality of life — to WAM questionnaires.

Results. The study surveyed 92 students aged 20.7 ± 0.2 years (56 men and 36 women). We report borderline manifestations of functional disorders of the gastrointestinal tract (GIT) in 51.1 %, and FD and/or IBS symptoms of mild to moderate severity in 23.9 % of respondents. Symptoms of FD and/or IBS were equally common in men and women. Severity of FD and/or IBS symptoms was rated 4 [[3; 7] in men and 4 [[4; 11] in women (p = 0.25). Physical activity of 57.6 % in students corresponded to a moderate level. Healthy students were more likely to exhibit higher physical activity than individuals with FD and/or IBS symptoms, 56.5 and 31.9 %, respectively (p = 0.04). The level of wellbeing and severity of FD and/or IBS symptoms correlated negatively (r = –0.28, p = 0.01). Wellbeing and mood correlated directly with physical activity, r = 0.33, p = 0.001 and r = 0.27, respectively (p = 0.01).

Conclusions. 1. Symptoms of FD and/or IBS occur widely among students and equally in men and women. Functional disorders of the gastrointestinal tract of mild to moderate severity occur in 23.9 % of students, with borderline symptoms registered with every second individual. 2. Healthy students significantly more often exhibited higher physical activity compared to individuals with FD and/or IBS symptoms of varying severity in the ratios of 56.5 and 31.9 % (p = 0.04). 3. Severity of FD and/or IBS in students negatively correlates with the wellbeing component of quality of life (r = –0.28, p = 0.01).

Background. Preoperative biopsy is recommended for morphological verification of colorectal epithelial neoplasms prior to their endoscopic resection. However, histological reports for endoscopic biopsy and resected lesions are not reliably consistent.

Aim. Assessment of sensitivity, specificity and accuracy of endoscopic biopsy in differential diagnosis of colorectal serrated adenomas and risk factors for variance between biopsy results and morphological examination of completely resected lesions.

Materials and methods. The assay used data on 56 morphologically verified serrated adenomas diagnosed and resected in 50 patients (14 men, 36 women; average age 66.9 ± 10.5 years). Biopsy was taken from all tumours before endoscopic resection. Results of morphological examination of biopsy samples and resected tumours were analysed and compared. Sensitivity, specificity and accuracy of biopsy was assessed, with the tumour size and type and biopsy forceps system taken as criteria.

Results. The identified cases included 22 (39.3%) right-colon, 21 (37.5%) left-colon and 13 (23.2%) rectal lesions of 28.5 ± 2.6 mm average size. Polypoid were 17 (30.3%), non-polypoid — 6 (10.7%) and spreading — 33 (59%) of the tumours. Full consistency of morphological examination was observed for 12 cases (21.4%). In 9 cases (16%), dysplasia was established as mild-graded with biopsy, whilst the eradicated tumours contained severe dysplastic foci. Foci of adenocarcinoma were detected in 10 tumours (including 2 with submucosal invasion), but only 2 cases were correctly diagnosed for malignant adenoma with biopsy. Tumour morphology was misidentified in 32 cases (57.1%).

Conclusions. Preoperative forceps biopsy is shown to possess low sensitivity in differential diagnosis of serrated colorectal lesions and very low sensitivity to predict malignant serrated adenomas.

Aim. Evaluation of sarcopenia’s effect on hepatotoxicity in patients with locally advanced and metastatic pancreatic cancer (PC).

Materials and methods. A retro-prospective study included 66 patients (30 men and 36 women) with locally advanced and metastatic PC receiving chemotherapy treatment in the form of gemcitabine monotherapy and in combination with platinum, taxanes, fluoropyrimidines in standard chemotherapy protocols. Sarcopenia was observed using computer tomography with intravenous bolus contrast and nonionic contrast medium with iodine concentration 350 mg/ml. Muscle tissue area (cm²) was estimated with two consecutive axial slices at the level of L3 lumbar vertebra. Sarcopenia was determined with the L3 skeletal muscle index (L3SMI) calculated as a ratio of skeletal muscle area at the L3 vertebra to patient’s height squared. Condition was marked as sarcopenia at L3SMI values of 52.4 cm²/m² in men and 38.5 cm²/m² in women.

Results. Hepatotoxicity was revealed in 57.5% (n = 38) of PC patients receiving chemotherapy, with 60.87% (n = 28) of them having sarcopenia. In patients with sarcopenia and no toxic effects, the total survival median was 41 months, whilst hepatotoxicity combined with sarcopenia was associated with almost a 3 times lower median survival (14.1 months). A better survival trend was observed in a polychemotherapy cohort without sarcopenia, with the total survival median of 17.0 months compared to 15.2 months in such patients with sarcopenia (p = 0.781). A positive trend towards survival was observed in a hepatotoxicity-negative cohort, with the total survival median of 18.7 months compared to 16.9 months in PC patients with toxic side effects (p = 0.174).

Conclusions. Sarcopenia may be used as a prognostic factor of lower survival rate and higher hepatotoxic effect of chemotherapy in patients with locally advanced and metastatic pancreatic cancer.

Aim of review. Interpretation of published evidence on the relationship between the excessive belching syndrome and functional dyspepsia (FD) and their management in patient care.

Key points. According to the Rome IV criteria of functional gastrointestinal disorders (FGID), excessive belching in the absence of other dyspeptic symptoms is to be considered a manifestation of the excessive belching syndrome, which can be of gastric or supragastric nature. Combination of high-resolution manometry and impedancemetry allows an accurate diagnosis of belching and selection of optimal treatment strategy. Belching complicated by other symptoms of dyspepsia is to be considered yet another FD symptom according to the Rome IV criteria of FGID. Prokinetics are recommended to relieve belching in such cases.

Conclusion. Understanding the relationship between the excessive belching syndrome and FD requires further research.

Aim. Current recommendations of the Russian Gastroenterological Association on clinical use of high-resolution manometry in diagnosis of esophageal disorders are intended to assist in clinical decision making, terminology standardisation and interpretation of clinical data.

Key points. In 2018, a joint meeting of the Russian Gastroenterological Association and Russian Neurogastroenterology and Motility Group approved unified terminology and classification of esophageal motor function disorders for high-resolution manometry diagnosis.

Gastrointestinal patient complaints typically concern esophageal disorders such as dysphagia, regurgitation, heart-burn, chest pain or belching. To exclude erosive and ulcerative lesions, eosinophilic esophagitis and organic changes, esophagogastroduodenoscopy and biopsy are recommended in pre-treatment. Upon excluding mucosal lesions and esophageal lumen obstruction as causal for symptoms, use of high-resolution manometry is recommended. This method of esophageal examination has become the “gold standard” in diagnosis of motor disorders.

High-resolution manometry enables detailed investigation of integral quantitative and qualitative characteristics of esophagus motor function and specific related disorders, analysis of esophageal contractile propagation and strictly coordinated synchronous peristalsis of upper esophageal sphincter, esophagus and lower esophageal sphincter, which malfunction may provoke development of achalasia, esophagospasm, hiatal hernia, ineffective eso pha geal motility and other motor disorders.

Conclusion. High-resolution manometry is a relatively new method for study of esophagus motor function gaining increasingly wide application in clinical practice. It enables a medical professional to obtain evidence that may critically affect the choice of optimal patient care strategy and effective treatment. Current recommendations are based on an extensive review of up-to-date information and will be updated with new corpus of clinical data and assessment emerging in evidential medicine to provide gastroenterologists country-wide with latest scientific and practical guidelines.