Phenotypic features of patients with post-infectious irritable bowel syndrome

Contribution of sex and gender roles to the incidence of post-infectious irritable bowel syndrome in a prospective study

Post-infectious irritable bowel syndrome (PI-IBS) occurs in about 10% of cases following gastroenteritis. The incidence of IBS is higher in females. However, it is not clear whether this is due to biological or psychosocial factors. We aimed to investigate the influence of gender roles on the incidence of PI-IBS, alongside traditional risk factors. Our study included 231 patients diagnosed with gastroenteritis who were hospitalized and treated with antibiotics between 2018 and 2021. The Korean Sex Role Inventory-Short Form (KSRI-SF), based on the Bem Sex Role Inventory (BSRI) was used to categorize patients (androgynous, masculine, feminine, and undifferentiated types). Six months after treatment, we conducted a telephone survey to confirm the presence of PI-IBS using the ROME IV criteria. Among the patients, 43.3% were female, and the mean age was 43.67 ± 16.09 years. After 6 months, 34 patients developed PI-IBS. Univariate analysis revealed that younger age, female sex, KSRI-SF undifferentiated type, and longer duration of antibiotic use independently influenced the occurrence of PI-IBS. Multivariate analysis showed that PI-IBS was associated with the KSRI-SF undifferentiated type and higher C-reactive protein (CRP) levels. Our study showed that the KSRI-SF undifferentiated type and high CRP levels at initial infection were associated with PI-IBS.

[Irritable bowel syndrome phenotypes: leading factors of genetics and epigenetics, mechanisms of formation]

AIM

To develop individualized approaches to the treatment of irritable bowel syndrome (IBS) based on the interaction of genetic and epigenetic factors, to characterize the phenotypes of the disease.

MATERIALS AND METHODS

According to the formulated concept of the authors, from the cohort of patients with IBS, subgroups were distinguished - "post-infectious IBS" (n=45), "IBS in overweight and obese people" (n=49), "comorbid IBS" (n=75) and "essential IBS" (n=51). In each subgroup the prevalence of candidate gene polymorphisms associated with IBS (COMT, SLC6A4, FTO), nutritional habits, levels of anxiety and depression, secretion of cortisol, serotonin, dopamine and zonulin levels in feces were studied.

RESULTS

Patients with "post-infectious IBS" are characterized by the carriage of the S allele of the SLC6A4 gene, the val/val genotype of the COMT gene, the prevalence of diarrhea, a high level of anxiety and frequent refusal of milk and dairy products. The phenotype "IBS in overweight and obese individuals" is characterized by L/L genotypes of the SLC6A4 gene, met/met of the COMT gene and A/A of the FTO gene, constipation, low plasma dopamine levels, signs of depression, frequent episodes of overeating, addiction to fatty and sweet foods, excessive consumption of sugar, lack of vegetables in the diet. The "comorbid IBS phenotype" is characterized by more frequent detection of the val/val genotype of the COMT gene and the carriage of the S allele of the SLC6A4 gene, clinically pronounced anxiety and depression, early onset of the disease, severe course, significant food restrictions and significant increase in epithelial permeability. With the "essential phenotype", there are no bright stigmas of the disease; it is not possible to identify distinctive genetic and epigenetic factors, as well as the leading pathogenetic mechanism.

CONCLUSION

The analysis of genetic and epigenetic factors, the leading mechanisms of the formation and course of IBS allows us to identify additional (except for "postinfectious") phenotypes of the disease: "IBS in overweight and obese people", "comorbid" and "essential".

Visceral sensitivity index of patients with irritable bowel syndrome after COVID-19 infection

Aim. To perform comparative analysis of visceral sensitivity index (VSI) of patients with previously diagnosed irritable bowel syndrome (IBS) and of patients with IBS symptoms after COVID-19 infection. Materials and methods. The study was carried out on the basis of University Clinical Hospital №1; 200 patients with COVID-19 infection were examined. Selection criteria were the recommendations of the Rome Consensus IV (2016). Fourteen patients met the criteria for IBS (Rome IV). Forty patients with a verified diagnosis of IBS before the COVID-19 pandemic (Group 2) were selected as a comparison group. The control group included 50 healthy respondents (group 3). Group 1 included 14 patients; Group 2 included 40 patients (54 patients in total): 37 women and 17 men. The control group included 50 patients: 23 men and 27 women. VSI was estimated in the studied groups. Results. No statistically significant difference of VSI index (p0.05) was revealed while comparing two studied groups (group 1 and group 2). In group 1 and group 2 the mean values of VSI were 24.575.47 and 33.982.55 respectively. Absence of significant differences allows to assume from the position of biopsychosocial model that the patients were initially predisposed to IBS development. Conclusion. A new coronavirus infection is one of the triggers for the development of IBS 6 months after COVID-19 infection.

Bifidobacterium bifidum and Bacteroides fragilis Induced Differential Immune Regulation of Enteric Glial Cells Subjected to Exogenous Inflammatory Stimulation

Enteric glial cells (EGCs) are involved in intestinal inflammation. In this study, we will investigate how Bifidobacterium bifidum (B.b.) and Bacteroides fragilis (B.f.) influence EGC regulation. After pretreatment with lipopolysaccharide (LPS) and interferon-γ (IFN-γ), the expressions of major histocompatibility complex class II (MHC-II), CD80, CD86, glial cell line-derived neurotrophic factor (GDNF), toll-like receptor 2 (TLR-2), and tumor necrosis factor-α (TNF-α) in EGCs were detected using polymerase chain reaction and western blot after co-culture with the supernatants of B.b. or B.f. (multiplicity of infection, 40:1 or 80:1). Finally, EGCs were co-cultured with naive CD₄⁺ T cells, and the expressions of interleukin (IL)-2, IL-4, IL-10, and IL-17 in supernatant were measured using enzyme-linked immunosorbent assay (ELISA). The mRNA expressions of MHC-II and CD86 in EGCs were increased after combined stimulation with LPS and IFN-γ. The expressions of MHC-II, GDNF, TLR-2, and TNF-α were all significantly upregulated in stimulated EGCs. The B.b. supernatant downregulated the expressions of MHC-II, GDNF, TLR-2, and TNF-α in stimulated EGCs, whereas the B.f. supernatant upregulated TLR-2 expression and downregulated MHC-II expression. The expressions of IL-4, IL-2, and IL-17 after co-culture of naive CD₄⁺ T cells and stimulated EGCs were significantly increased. The supernatant of B.b. or B.f. downregulated the expressions of these cytokines. The low-concentration B.b. supernatant upregulated IL-10 expression. Conclusions B.b. and B.f. may influence intestinal inflammation by regulating MHC-II, GDNF, TLR-2, and TNF-α expression in EGCs and IL-4, IL-2, IL-17, and IL-10 secretion.