Post-infectious irritable bowel syndrome: renaissance time?

Postinfectious irritable bowel syndrome (PI–IBS) is a distinct phenotype of the disease. The occurrence of gastrointestinal symptoms in PI–IBS is in direct chronological connection with an episode of acute intestinal infection. Previously the problem was considered as the outcome of parasitic, protozoal or bacterial infection. The global spread of a novel coronavirus infection (COVID-19) and increase in the number of new cases of IBS in the population suggests a renaissance of PI–IBS and makes us look at this problem again. This article summarizes and presents modern information on the possible mechanisms of development of PI–IBS, including in persons who have undergone COVID-19.

Screening methods for assessing the nutritional status of young children with intestinal infection

Assessment of the nutritional status in children with infectious pathology is an important and necessary event in the routine practice of a pediatrician. The article describes the basic principles of assessing the nutritional status of children with intestinal infections. The main laboratory markers are shown, changes in which may indicate the risk of developing nutritional insufficiency and a more severe course of the disease. In the conditions of an infectious hospital, screening methods for assessing the nutritional status can be used. There are different scales and tools for screening, further research is needed to identify the most optimal method.

Routes of Spread of Anthrax in Natural Ecosystems

Anthrax is a particularly dangerous zooanthroponosis caused by the Gram-positive spore-forming bacterium Bacillus anthracis. This disease mainly affects hoofed herbivores, including those used in agriculture, but can occur in other animals and in humans. That is why the majority of studies of this infection are focused on anthrax in humans and farm animals, as the most important issues from a practical point of view. At the same time, the issues of anthrax epidemiology in natural ecosystems are described in the literature in insufficient detail and often very fragmentary. This paper provides a review of the literature describing the main pathways, patterns and risks of the spread of various clinical forms of anthrax infection in nature, primarily among wild animals. Among other things, we cover some non-notable aspects of intestinal infection with anthrax which, for instance, explain the difference in sensitivity to infection in herbivorous and carnivorous mammals and even different sex and age groups within the same species.

Clinical case of combined intestinal infection caused by enteroaggregative Escherichia coli and toxigenic strain Clostridium difficile in a child with cystic fibrosis

The goal is to study the peculiarities of the clinical picture and the distant outcome of intestinal infection due to enteroaggregative escherichiosis and the toxigenic strain of C. difficile in a child with cystic fibrosis.Material and methods. To verify the etiology of intestinal infection, the following studies were conducted. — fecal PCR “OKI-screen” tests to detect viral and bacterial pathogens, fecal bacteriopsy for pathogenic and opportunistic microbes; determination of C. difficile A and B toxins in feces by enzyme-linked fluorescence analysis.Results. The combined intestinal infection caused by en-teroaggregative escherichiosis and a toxigenic strain of C. difficile, in a child with pulmonary-intestinal form of cystic fibrosis was characterized by a wavy course, a pronounced intoxication syndrome, excicosis, hemorrhagic enterocolitis, signs of systemic and local inflammation, metabolic disorders. There were no recurrences of C. difficile-infection in catamnese.Conclusion. It is necessary to continue research on the course of intestinal infections caused by bacterial associations of pathogens.

Protective and Anti-Inflammatory Effects of Protegrin-1 on Citrobacter rodentium Intestinal Infection in Mice

Infectious intestinal colitis, manifesting as intestinal inflammation, diarrhea, and epithelial barrier disruption, affects millions of humans worldwide and, without effective treatment, can result in death. In addition to this, the significant rise in antibiotic-resistant bacteria poses an urgent need for alternative anti-infection therapies for the treatment of intestinal disorders. Antimicrobial peptides (AMPs) are potential therapies that have broad-spectrum antimicrobial activity due to their (1) unique mode of action, (2) broad-spectrum antimicrobial activity, and (3) protective role in GI tract maintenance. Protegrin-1 (PG-1) is an AMP of pig origin that was previously shown to reduce the pathological effects of chemically induced digestive tract inflammation (colitis) and to modulate immune responses and tissue repair. This study aimed to extend these findings by investigating the protective effects of PG-1 on pathogen-induced colitis in an infection study over a 10-day experimental period. The oral administration of PG-1 reduced Citrobacter rodentium intestinal infection in mice as evidenced by reduced histopathologic change in the colon, prevention of body weight loss, milder clinical signs of disease, and more effective clearance of bacterial infection relative to challenged phosphate-buffered saline (PBS)-treated mice. Additionally, PG-1 treatment altered the expression of various inflammatory mediators during infection, which may act to resolve inflammation and re-establish intestinal homeostasis. PG-1 administered in its mature form was more effective relative to the pro-form (ProPG-1). To our knowledge, this is the first study demonstrating the protective effects of PG-1 on infectious colitis.

The fliR gene contributes to the virulence of S. marcescens in a Drosophila intestinal infection model

Serratia marcescens is an opportunistic bacterium that infects a wide range of hosts including humans. It is a potent pathogen in a septic injury model of Drosophila melanogaster as five bacteria directly injected in the body cavity of the fly kill the host within a day. In contrast, flies do not succumb to ingested bacteria for days even though some bacteria traverse the intestinal barrier into the hemolymph within a couple of hours. The mechanisms by which S. marcescens attacks enterocytes and damages the intestinal epithelium remain uncharacterized. To better understand intestinal infections, we performed a genetic screen for loss of virulence of ingested S. marcescens in which we identified FliR, a structural component of the flagellum, as a virulence factor. Next, we compared the virulence of two flagellum mutants fliR and flhD using two Serratia strains. Both genes are required for S. marcescens to escape the gut lumen into the hemocoel indicating that the flagellum plays an important role for the passage of bacteria through the intestinal barrier. In contrast, fliR but not flhD is needed to severely damage the intestinal epithelium and ultimately kill the host. Our results therefore suggest a flagellum-independent role for fliR in bacterial virulence.

Tactics of a general practitioner in identifying a case of acute intestinal infection

Acute intestinal infection refers to a group of acute infectious diseases, mainly of bacterial origin, with an alimentary transmission mechanism, which is based on a combination of fever with intestinal syndrome with the possible development of dehydration and severe course in children and the elderly. Every day in the world, about 12 million people are affected by acute intestinal infections, while about 4 billion cases of these diseases are recorded annually. In the developing countries of Asia, Africa, and Latin America, acute intestinal infections are the main cause of death in young children. The main causative agents of intestinal infections are Shigella, Salmonella, Escherichia coli, and rotavirus infection. This type of intestinal diseases is characterized by an acute onset, a rapid development of a temperature reaction, the appearance of symptoms of intoxication and exicosis, vomiting, diarrhea, pain in the epigastric and umbilical region, pain on palpation of the abdomen (salmonella triangle), hepatosplenomegaly. In this case, the feces are liquid, watery, with undigested food residues, mucus, have the color of "swamp mud", sometimes with an admixture of blood. When a case of acute intestinal infection is detected, the physician's tactics should consist in the timely identification and isolation of patients; conducting final disinfection in the outbreak focus; organization of bacteriological examination of contact persons; conducting sanitary and educational work among the population; as well as dispensary observation of recovered patients.