SUCCESSFUL EXPERIENCE WITH FAECALMICROBIOTA TRANSPLANTATIONIN A PATIENT WITH MYELODYSPLASTIC SYNDROMEAND GRAFT-VERSUS-HOST REACTION WITHINTESTINAL LESIONS COMBINEDWITH ENTEROCOLITIS CAUSEDBY CLOSTRIDIUM DIFFICILE INFECTION:A CLINICAL CASE

Relevance: Faecal microbiota transplantation (FMT) is the transfer of intestinal contents from a healthy donor to a patient to restore normal microflora. The material contains beneficial bacteria, fungi, antibodies, prebiotics, and other biologically active components. FMT is most effectively used for recurrent Clostridium difficile infection, showing better results compared to traditional treat-ment, such as vancomycin. Studies also suggest the potential of FMT in treating inflammatory bowel diseases, obesity, metabolic syndrome, and gastrointestinal tract functional disorders. In recent years, the method has gained widespread recognition and is now considered a potential first-line therapy for Clostridium difficile. The study aimed to present the first successful clinical experience of faecal microbiota transplanta-tion in a patient with myelodysplastic syndrome and graft-versus-host disease, characterized by in-testinal lesions. Methods: A clinical case of a 46-year-old patient who underwent allogeneic bone marrow trans-plantation for myelodysplastic syndrome is described. In the early post-transplantation period, the patient developed severe manifestations of Graft-versus-host disease (GvHD) with predominant in-volvement of the gastrointestinal tract: severe diarrhoea, abdominal pain, weight loss, signs of dysbiosis, and nutritional deficiency. After ineffective therapy with steroids and supportive care, a decision was made to perform FMT using carefully selected donor material. Results. The FMT procedure was clinically successful, with improvements in general condition, a decrease in the severity of diarrhea, stabilization of body weight, and restoration of appetite noted within several days. Endoscopic and histological examinations of the intestinal mucosa confirmed a reduction in inflammatory changes. No side effects, complications, or signs of systemic infection were recorded after FMT. Conclusions. The successful application of FMT in this case demonstrates the potential of the meth-od as an additional therapeutic tool in (GvHD) with intestinal involvement, particularly in steroid-resistant forms of the disease