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In vitro analysis of the bactericidal activity of Escherichia coli Nissle 1917 against pediatric uropathogens
Douglas W Storm1, Stephen A Koff, Dennis J Horvath
1Department of Urology, Naval Medical Center, San Diego, California 92134-5000, USA. douglas.storm@med.navy.mil
Purpose:
The usefulness of prophylactic antibiotics to prevent recurrent urinary tract infections in children was recently questioned. Some groups have attempted to use probiotics, most commonly lactobacillus, to prevent recurrent infections by altering the intestinal bacterial reservoir with variable results. Mutaflor® is a possible alternative probiotic in which the active agent is Nissle 1917. Nissle 1917 is a commensal Escherichia coli strain that eradicates pathogenic bacteria from the gastrointestinal tract. Due to its ability to alter the intestinal biome we hypothesized that Mutaflor may have the potential to prevent recurrent urinary tract infections. Thus, we used an in vitro assay to analyze the effectiveness of Nissle 1917 for eradicating pediatric uropathogens.
Materials And Methods:
We established a collection of 43 bacterial pediatric uropathogens. With each isolate a microcin-type assay was performed to determine the effectiveness of Nissle 1917 on bacterial growth inhibition and competitive overgrowth.
Results:
Nissle 1917 adversely affected the growth of 34 of the 43 isolates (79%) isolates. It inhibited the growth of 21 isolates and overgrew 13. The percent of species adversely affected by Nissle 1917 was 40% for Pseudomonas, 50% for E. coli, Enterococcus and Staphylococcus, 100% for Klebsiella and Enterobacter, and 0% for Citrobacter and Serratia.
Conclusions:
Nissle 1917, the active agent in Mutaflor, inhibited or out competed most bacterial isolates. These mechanisms could be used in vivo to eradicate uropathogens from the gastrointestinal tract. Further study is needed to determine whether Mutaflor can prevent recurrent urinary tract infections in children.
Insights
The probiotic Nissle 1917 (Mutaflor) inhibited or outcompeted 79% of pediatric uropathogens in vitro. This suggests potential for preventing recurrent urinary tract infections by targeting the gut microbiome.
Area of Science:
- Microbiology
- Pediatric Infectious Diseases
- Gastroenterology
Background:
- Recurrent urinary tract infections (UTIs) in children are a concern, with prophylactic antibiotics being questioned.
- Probiotics, like Lactobacillus, have shown variable results in preventing UTIs by altering the gut microbiome.
- Mutaflor, containing the probiotic strain Nissle 1917, is explored for its potential to prevent pediatric UTIs.
Purpose of the Study:
- To investigate the in vitro effectiveness of Nissle 1917 against pediatric uropathogens.
- To determine if Nissle 1917 can inhibit growth or outcompete common UTI-causing bacteria.
Main Methods:
- A collection of 43 pediatric uropathogen isolates was established.
- A microcin-type assay was employed to assess Nissle 1917's impact on bacterial growth inhibition and competitive overgrowth.
Main Results:
- Nissle 1917 adversely affected the growth of 79% (34/43) of the tested pediatric uropathogens.
- Inhibition of growth was observed for 21 isolates, while 13 were outcompeted.
- Effectiveness varied by species, with Klebsiella and Enterobacter (100%) and Pseudomonas (40%) showing susceptibility.
Conclusions:
- Nissle 1917 demonstrates significant in vitro antimicrobial activity against a majority of pediatric uropathogens.
- These findings suggest a potential mechanism for eradicating uropathogens from the gastrointestinal tract in vivo.
- Further clinical studies are warranted to confirm Mutaflor's efficacy in preventing recurrent UTIs in children.
