Probiotics for Prophylaxis and Treatment of Urinary Tract Infections in Children

An exploratory in silico analysis of bacteriocin gene clusters in the urobiome

Background: The role of the urobiome in health and disease remains an understudied area compared to the rest of the human microbiome. Enhanced culturing techniques and next-generation sequencing technologies have identified the urobiome as an untapped source of potentially novel antimicrobials. The aim of this study was to screen the urobiome for genes encoding bacteriocin production. Methods: The genomes of 181 bacterial urobiome isolates were screened in silico for the presence of bacteriocin gene clusters using the bacteriocin mining tool BAGEL4 and secondary metabolite screening tool antiSMASH7. Results: From these isolates, an initial 263 areas of interest were identified, manually annotated, and evaluated for potential bacteriocin gene clusters. This resulted in 32 isolates containing 80 potential bacteriocin gene clusters, of which 72% were identified as class II, 13.75% as class III, 8.75% as class I, and 5% as unclassified bacteriocins. Conclusion: Overall, 53 novel variants were discovered, including nisin, gassericin, ubericin, and colicins.

Effect of Probiotics on Urinary Tract Infections in Children: A Systematic Review and Meta-Analysis

BACKGROUND

Urinary tract infections (UTIs) are the most prevalent bacterial infections that occur in children worldwide.

OBJECTIVE

This meta-analysis aims to investigate the utility of probiotics as preventive therapy in children with a UTI.

METHODS

The Web of Science, PubMed, and Scopus were searched for articles that investigated the relationship between probiotic consumption and the risk of UTIs. The quality of the articles was evaluated using the Jadad scale. The pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using a random-effects model. Subgroup analyses and sensitivity analyses were also conducted. The Cochran Q test and the statistic I2 were used to evaluate heterogeneity. To determine any potential publication bias, the Egger's and Begg's tests were used.

RESULTS

In total, eleven studies were selected for the systematic review and meta-analysis. Compared to children who did not receive probiotics, the OR of developing or having a recurring urinary tract infection in those who received probiotics was 0.94 (95% CI; 0.88-0.999; p-value=0.046). The Begg's and Egger's tests showed no evidence of publication bias between probiotics and the risk of developing new or recurring urinary tract infections.

CONCLUSION

Based on this systematic review and meta-analysis, probiotics could be an alternative therapy for children who are at risk of developing a UTI. They are non-pharmaceutical options and could be used as natural prophylaxis for UTIs. However, the currently published evidence does not irrefutably confirm that probiotics provide a protective effect against urinary bacterial infections. Therefore, there need to be large-scale randomized clinical trials undertaken to investigate the possible prophylaxis of probiotics.

Relationship between intestinal microbiota, diet and biological systems: an integrated view

The health-disease process can be influenced by the intestinal microbiota. As this plays a fundamental role in protecting the organism, the importance of studying the composition and diversity of this community becomes increasingly evident. Changes in the composition of the intestinal bacterial community may result in dysbiosis, and this process may contribute to triggering various diseases in all biological systems. This imbalance of intestinal microbiota homeostasis may alter commensal bacteria and the host metabolism, as well as immune function. Dysbiosis also causes an increase in intestinal permeability due to exposure to molecular patterns associated with the pathogen and lipopolysaccharides, leading to a chronic inflammatory process that can result in diseases for all biological systems. In this context, dietary intervention through the use of probiotics, prebiotics and antioxidant foods can be considered a contribution to the modulation of intestinal microbiota. Probiotics have been used to provide up to 10 billion colony forming units, and probiotic foods, Kefir and fermented natural yogurt are also used. Prebiotics, in turn, are found in supplemental formulations of processed foods and in functional foods that are also sources of phenolic compounds, such as flavonoids, antioxidant and anti-inflammatory substances, polyunsaturated fatty acids, vitamins, and minerals. In this review, we will discuss the relationship between an imbalance in the intestinal microbiota with the development of diseases, besides indicating the need for future studies that can establish bacterial parameters for the gastrointestinal tract by modulating the intestinal microbiota, associated with the adoption of healthy habits during all life cycles.

Lactic Acid Bacteria and Their Bacteriocins: Classification, Biosynthesis and Applications against Uropathogens: A Mini-Review

Several lactic acid bacteria (LAB) isolates from the Lactobacillus genera have been applied in food preservation, partly due to their antimicrobial properties. Their application in the control of human pathogens holds promise provided appropriate strains are scientifically chosen and a suitable mode of delivery is utilized. Urinary tract infection (UTI) is a global problem, affecting mainly diabetic patients and women. Many uropathogens are developing resistance to commonly used antibiotics. There is a need for more research on the ability of LAB to inhibit uropathogens, with a view to apply them in clinical settings, while adhering to strict selection guidelines in the choice of candidate LAB. While several studies have indicated the ability of LAB to elicit inhibitory activities against uropathogens in vitro, more in vivo and clinical trials are essential to validate the efficacy of LAB in the treatment and prevention of UTI. The emerging applications of LAB such as in adjuvant therapy, oral vaccine development, and as purveyors of bioprotective agents, are relevant in infection prevention and amelioration. Therefore, this review explores the potential of LAB isolates and their bacteriocins to control uropathogens, with a view to limit clinical use of antibiotics.