Molekulare Darmmikrobiomdiagnostik: Einblick in unser anderes Genom

Microscopic colitis: controversies in clinical symptoms and autoimmune comorbidities

BACKGROUND

Microscopic colitides are chronic immune-inflammatory bowel diseases. The typical presentation is chronic, watery diarrhoea. Inflammation mostly cannot be visualized via macroscopic inspection. The diagnosis thus requires histologic sampling. The clinical picture can vary. New investigations can prove valuable in setting up recommendations.

PATIENTS

A total of 103 patients with microscopic colitis (MC) [28 lymphocytic colitis (LC) 27.2%, 75 collagenous colitis (CC) 72.8%] in the Clinical Centre of the University of Debrecen (tertiary care centre) were included, diagnosed between 1993 and 2020. We aimed for a retrospective analysis characterizing Hungarian MC patients. We sought to compare two subgroups of patients (with either LC or CC). Our investigation focussed on dominant alteration of stool habits, autoimmune and allergic comorbidities. Autoimmune diseases were diagnosed in 39% (40) of the patients, allergic diseases in 26.2% (27) of patients and 22.2% of tested patients had alimentary hypersensitivity to certain foods (18 cases out of 81 tested).

RESULTS

Age of diagnosis was younger in LC (44.5 years, SD: 5.3 vs. 51.9 years, SD: 12.8, difference= 7.4 years p = .0151). Autoimmune diseases were equally frequent in the two groups (LC: 10 patients 36%, CC: 30 patients, 40%, difference: 4%, p = .7124). Food-linked hypersensitivities were more common in CC (LC: 1 patient, CC: 17 patients). Difference in allergic diseases (asthma, rhinitis, urticaria) did not differ between groups (LC: 6 patients, 21%; CC: 21 patients, 28%, difference: 7% p = .4739). One-third of the patients did not complain about chronic diarrhoea. These patients had chronic constipation as the main symptom (34 patients, 33%).

CONCLUSION

Pre-existing autoimmune and allergic diseases were common in patients with MC. Chronic watery diarrhoea is not experienced in many cases. The absence of certain symptoms should not be used to rule out the condition.

Vitamin D deficiency and risk of Helicobacter pylori infection in older adults: a cross-sectional study

BACKGROUND

Vitamin D deficiency is known to cause increased predisposition to various infectious diseases and the addition of vitamin D to antimicrobial treatment may improve treatment responses. However, the relationship between vitamin D and Helicobacter pylori (H. pylori) remains to be determined.

AIMS

To assess the association between vitamin D deficiency and H. pylori infection.

METHODS

This cross-sectional study included patients aged 65 and over, who underwent gastroscopy and had gastric biopsy performed between 2010 and 2017. Of the 441 patients, 254 had available 25-hydroxyvitamin D level results and were included in the analyses. Patients were categorized into H. pylori (+) and H. pylori (-) groups, according to histopathological examination results of gastric biopsies. Serum 25(OH) vitamin D levels less than 20 ng/mL were defined as vitamin D deficiency.

RESULTS

Of all patients, 43 were H. pylori (+) and 211 were H. pylori (-). More patients had vitamin D deficiency (< 20 ng/mL) in the H. pylori (+) group than the H. pylori (-) group (86% vs 67.3%, p = 0.014). The proportion of H. pylori (+) patients decreased across increasing quartiles of 25(OH) vitamin D levels (p for trend = 0.010). In multivariable logistic regression analysis, vitamin D deficiency was associated with increased odds of H. pylori infection after adjustment for age, gender, and Charlson Comorbidity Index (OR = 3.02, 95% CI 1.19-7.69, p = 0.020).

CONCLUSION

Vitamin D deficiency can be associated with increased risk of H. pylori infection. The potential protective effect of vitamin D against H. pylori infection and its possible role in the treatment of H. pylori should be evaluated in prospective trials.

Coeliac disease: beyond genetic susceptibility and gluten. A narrative review

Coeliac disease (CD) is an immune-mediated disorder triggered by the ingestion of gluten in genetically susceptible individuals. However, only a small proportion of subjects harbouring CD-related genetic risk develop the disease. Among the environmental factors that may influence CD risk, pre- and perinatal factors, delivery methods, parental lifestyle, infant feeding practices, seasonality, dietary factors, drug use, childhood infections and variability in gut microbiota are those most widely studied regarding the risk to develop CD. Although for many of these external factors the exact mechanism of action is unknown, most of them are thought to act by disrupting the intestinal barrier, facilitating contact between potential antigens and the immune system effector cells. Management of CD is relatively easy in patients with a definite diagnosis and requires a strict, lifelong, gluten-free diet. Better knowledge of environmental exposures apart from gluten can facilitate understanding of the pathogenesis of the disorder and the wide heterogeneity of its clinical spectrum. The purpose of this review is to discuss current knowledge on environmental CD risk factors, as well as possible interaction between them, on the grounds of the reliable scientific evidence available. Key messages The risk of developing CD is influenced not only by gluten ingestion but also by a number of environmental factors including childhood infections and variability in gut microbiota, pre- and perinatal factors, infant feeding practices, delivery methods, parental lifestyle, seasonality, dietary factors and drug use, acting mainly by disrupting intestinal permeability. Better knowledge of exposure to these factors can facilitate their identification, and subsequent elimination, in the individual patient.