A recent study published in the journal Microorganisms by researchers from APC Microbiome Ireland, University College Cork, Atlantia Food Clinical Trials, Church & Dwight, and Verb Biotics has highlighted the potential benefits of the probiotic strain L. reuteri 3613-1 in managing urinary tract infections (UTIs).
The study confirms the strain’s ability to produce the bacteriocin reuterin through HPLC analysis, suggesting its potential effectiveness against microbes. “Our findings indicate a possible advantage in delaying the occurrence of recurrent suspected UTIs in women. Further research with larger sample sizes is needed,” the researchers noted.
Disruption of the Vaginal Microbiome
UTIs are a prevalent concern among women, representing up to 20% of infections seen in primary care settings across the U.S. It’s estimated that 50% of women will experience at least one UTI during their lifetime, costing the U.S. economy around $1.6 billion annually.
Various pathogens can cause these infections, including Gram-negative bacteria like Escherichia coli, Gram-positive bacteria such as Staphylococcus saprophyticus, Gram-variable bacteria like Gardnerella vaginalis, and yeasts such as Candida albicans. Notably, uropathogenic Escherichia coli (UPEC) is responsible for the majority of UTIs.
“UPEC primarily resides in the gastrointestinal tract, and studies show that bacteria from fecal matter can enter the urethra and bladder,” the researchers pointed out. “This underscores the importance of controlling UPEC proliferation, which may originate from both vaginal and fecal bacteria, thereby emphasizing the need for a comprehensive strategy in managing UTIs.”
The vaginal microbiome is predominantly made up of various Lactobacillus species that help maintain an acidic environment and produce antimicrobial substances, creating a defense against harmful pathogens.
“When the vaginal microbiome is disrupted, often due to a decrease in Lactobacillus species, the risk of UTIs escalates as it allows for a more favorable environment for pathogenic bacteria,” the researchers explained.
While oral and topical antibiotics are commonly prescribed to treat UTIs, they can disturb the balance of the vaginal microbiome, leading to an increased risk of subsequent infections and the potential for drug-resistant bacteria to emerge.
Probiotics have shown promise in promoting urinary and vaginal health, though clinical trials have yielded mixed results. Nevertheless, scientists have identified L. reuteri 3613-1 as a viable probiotic candidate for UTI prevention.
Study Details
The study involved a randomized, double-blind, placebo-controlled clinical trial with 130 women aged 18 to 65, who received daily oral supplementation of L. reuteri over a 24-week period. The researchers specifically examined the antimicrobial properties of Limosilactobacillus reuteri 3613-1 and its effect on UTI outcomes in women experiencing recurrent uncomplicated UTIs.
“In vitro tests showed that L. reuteri 3613-1 inhibited the growth of Escherichia coli isolates and demonstrated greater inhibitory effects against Gardnerella vaginalis and Candida albicans compared to another L. reuteri strain, with confirmed reuterin production and genomic profiling,” the researchers observed.
“While the occurrence, frequency, and severity of confirmed UTIs did not significantly differ between the study groups, L. reuteri 3613-1 did delay the onset of the first UTI, showing significance in participants with suspected but unconfirmed UTIs.”
The researchers concluded that L. reuteri 3613-1 holds promise as a probiotic option exhibiting antimicrobial properties, potentially delaying symptoms in women prone to recurrent UTIs. However, larger studies are warranted to confirm these findings.
The strain L. reuteri 3613-1 was identified from a collection of over 6,000 lactic acid bacteria in the Arm & Hammer research library due to its unique ability to produce antimicrobial metabolites. This strain generates reuterin, a powerful antimicrobial compound that can inhibit vaginal and urinary pathogens more effectively than other strains by up to 90%. It is versatile enough to be delivered via various formats, including powder mixes, cultured products, and capsules.
Source: Microorganisms. doi: 10.3390/microorganisms14030615. “Limosilactobacillus reuteri 3613-1 Delays Onset of Unconfirmed Urinary Tract Infections in Otherwise Healthy Women.” Authors: V. Turpin et al.
