Clinical and microbiological features of patients with irritable bowel syndrome after previous COVID‑19

Objective — to investigate clinical and microbiological features in patients with irritable bowel syndrome (IBS) after coronavirus disease 2019 (COVID‑19). Materials and methods. Examinations involved 68 patients aged 22 to 85 with IBS, including 37 (54.4%) women and 31 (43.6%) men. In 32 patients IBS occurred after COVID‑19 within a year before the study, and the other 36 patients had IBS without a history of COVID‑19. The control group included 30 practically healthy patients without gastrointestinal complaints. All patients were clinically diagnosed with IBS by the Rome criteria IV revision. Fecal samples were taken from each patient for further laboratory testing by a polymerase chain reaction to determine the representatives of obligate and opportunistic microflora. The statistical processing of the study data was performed using the Statistica software. Results. Diarrhea as the leading syndrome was recorded in 81.3% of cases in patients with post‑covid IBS, while patients with IBS without COVID‑19 more often had constipation — in 83.3% of cases. Changes were found in the number of obligate microorganisms during microbiome research: a decrease in the number of Bifidobacterium spp. in the group of patients with post­­COVID‑19 IBS compared to the other two groups, an increase in non‑pathogenic Escherichia coli was also recorded in this group compared to the other two groups, the lowest level of Bacteroides fragilis group was found in patients with non‑post‑COVID‑19 IBS, the highest level was observed in the group of healthy patients. No significant difference was found in the number of pathogenic microflora in all groups. Healthy patients had the greatest diversity of the studied microflora. Conclusions. Patients with irritable bowel syndrome that occurred after COVID‑19 had diarrhea as the most common symptom. The microbiome of such patients showed a decrease in the number of bacteria of the genus Bifidobacterium spp. and an increase in the level of non‑pathogenic Escherichia coli. The number of pathogenic microorganisms did not differ from that in other study groups.