Acute gastrointestinal infections (AGIs) can lead to significant morbidity and mortality. In diagnosing AGI, culture-independent diagnostic tests offer advantages over traditional methods and increase the chance of detecting multiple pathogens (co-detection). A retrospective analysis of data from a tertiary pediatric hospital was conducted to characterize occurrence of AGI co-detections and compare outcomes with patients who had only one AGI pathogen detected. Medical records were obtained for patients with stool samples tested using BioFire FilmArray GI Panel between 1 January 2016 and 31 December 2020. Data were described using descriptive statistics, correlation analysis, and logistic regression to identify risk factors and estimate co-detection rates. During the study period, 12,753 patients had a total of 17,159 stool samples tested. Of these, 8,212(47.9%) tested positive, with 6,040(73.6%) being single detections and 2,172(26.4%) being co-detections. Patients with single detection experienced higher hospitalization rates than patients with co-detection. Patients 1–4 years old exhibited the highest co-detection rate relative to other age groups, while Hispanic/Latino individuals were 1.75 times more likely to have co-detection than other races. This study emphasizes the significance of understanding pathogen interactions concerning clinical characteristics and epidemiology of AGI, and the necessity for effective diagnostic strategies and optimal healthcare resource allocation.

Health and wellbeing are challenged constantly by pathogens. A number of defence mechanisms exist to protect the body from pathogen colonisation and invasion, with an important role to play for the natural intestinal bacterial flora (mainly by bifidobacteria and lactobacilli). The present paper reviews the evidence on the effects of inulin and oligofructose on colonisation and translocation of pathogens and the prevention of intestinal diseases. In vitro experiments have shown that lactic acid-producing bacteria have antagonistic (antibacterial) activity against pathogens partly because of the production of organic acids which are the endproducts of inulin and oligofructose fermentation. In addition, studies with epithelial layers have shown that inulin and oligofructose inhibit pathogen colonisation and that endproducts of their fermentation have the ability to support barrier function. Furthermore, studies in various animal models have shown that inulin and oligofructose accelerate the recovery of beneficial bacteria, slow down pathogen growth, decreasing pathogen colonisation and systemic translocation. Finally, data from human intervention trials either in patients with intestinal disorders or disease, or prone to critical illness, found that inulin and oligofructose restore the balance when the gut microbial community is altered, inhibit the progression of disease or prevent it from relapsing and/or developing. To conclude, the dietary use of inulin and oligofructose offers a promising approach to restore microbial communities and to support barrier function of the epithelia by their prebiotic action. This may offer the host protection against invasion and translocation of pathogens (endogenous and/or exogenous) and in the prevention of gastrointestinal diseases.

The adhesion of Lactobacillus rhamnosus GG to human enterocyte-like Caco-2 cells was not inhibited by eight carbohydrates tested, namely N-acetyl-glucosamine, galactose, glucose, fructose, fucose, mannose, methyl-α-D-mannopyranoside and sucrose. The degree of hydrophobicity predicted the adhesion of L. rhamnosus GG to Caco-2 cells. L. rhamnosus GG, however, was able to compete with Escherichia coli and Salmonella spp. of low hydrophobicity and high adhesin–receptor interaction for adhesion to Caco-2 cells. The interference of adhesion of these gastrointestinal (GI) bacteria by L. rhamnosus GG was probably through steric hindrance, and the degree of inhibition was related to the distribution of the adhesin receptors and hydrophobins on the Caco-2 surface. A Carbohydrate Index for Adhesion (CIA) was used to depict the binding property of adhesins on bacteria surfaces. CIA was defined as the sum of the fraction of adhesion in the presence of carbohydrates, with reference to the adhesion measured in the absence of any carbohydrate. The degree of competition for receptor sites between Lactobacillus casei Shirota and GI bacteria is a function of their CIA distance. There were at least two types of adhesins on the surface of L. casei Shirota. The study provides a scientific basis for the screening and selection of probiotics that compete with selective groups of pathogens for adhesion to intestinal surfaces. It also provides a model for the characterisation of adhesins and adhesin–receptor interactions.