Prevention of nosocomial diarrhea using autostrains of lactobacilli isolated from wastewater and from the intestinal biotope of patients

Introduction. The work is devoted to evaluating the results of own studies on the possibility of using autostrains of lactobacilli isolated from wastewater and the intestinal biotope of patients, based on their antagonistic properties to prevent of nosocomial diarrhea associated with toxigenic Clostridioides difficile. There are presented results of studies on an animal model of antibiotic-associated diarrhea to determine the effectiveness of lactobacilli when eliminating toxigenic C. difficile.

Materials and methods. Studies were conducted on the antagonistic activity of clinical cultures of lactobacilli isolated from wastewater and intestinal biotope of patients against toxigenic strains of C. difficile isolated from patients with nosocomial diarrhea. Preclinical tests of the efficacy of the selected highly antagonistically active strain of Lactobacillus paracasei CTR079 in vivo were carried out in an animal model of C. difficile-associated infection in mice of the C57BL line.

Results. As a result of the studies, lactobacilli with high, medium, and without antagonistic activity were isolated. Antagonistically inactive strains were unable to inhibit the growth of C. difficile, unlike highly active strains. A strain of Lactobacillus paracasei CTR079 was selected to study the possibility of its use as a probiotic strain for the prevention and treatment of C. difficile associated infection in an in vivo experiment. Various changes in the intestinal epithelium as a result of the development of C. difficile-associated infection.

Limitations of the study. As part of the study, all isolated strains of lactobacilli were identified and stored for the study of biological, genetic properties, and production of bacteriocins.

Conclusion. As a result of the studies, the use of highly active strains of lactobacilli was established to be a promising direction for the prevention and treatment of nosocomial diarrhea, which will reduce the spread of C. difficile among patients and in the environment of medical institutions.

Compliance with ethical standards: conducting research on animals is approved by the local Ethical Committee on Bioethics of the Federal Scientific Center “All-Russian Research Institute of Experimental Veterinary named after K.I. Scriabin and Y.R. Kovalenko” of the Russian Academy of Sciences, the study was conducted in accordance with the European Convention for the Protection of Vertebrates Used for Experiments or Other Scientific Purposes (ETS N 123), Directive of the European Parliament and the Council of the European Union 2010/63/EC dated 22.09.2010 on the protection of animals used for scientific purposes (Protocol No. 2 of 16.07.2020).

Contribution of the authors:
Sukhina M.A. — research concept and design, data collection and processing, statistical processing, text writing, editing;
Yudin S.M. — editing;
Zagaynova A.V. — research concept and design, statistical processing.
All authors are responsible for the integrity of all parts of the manuscript and approval of its final version.

Acknowledgment. The study was carried out as part of the research work of the state task «Study of the prevalence, pathogenicity factors and mechanisms of antibacterial resistance of Clostridioides difficile» State Registration N АААА-А21-121012100073-8, «The effectiveness of the use of lactobacteria bacteriocins to combat multiresistant microorganisms associated with inflammatory diseases of the colon» State registration number АААА-А18-118122900073-2; state task No. 388-00099-23-02 within the framework of the implementation of applied research work on the topic: “Creation of a method for the treatment of antibiotic-associated diarrhea using autotransplantation of microaerophilic and obligate anaerobic bacteria of the large intestine” (code: “Autotransplantation”) and state contract «Development of unified methods, including sampling, for the determination of microbiological and parasitological pollution of wastewater» (code «Wastewater») N. 145.001.21.6 dated 12.11.2021.

Conflict of interest. The authors declare no conflict of interest.

Received: August 28, 2022
Accepted: January 19, 2023
Published: August 30, 2023