Currently, it takes between 24 and 48 hours to obtain the results of the test that identifies the bacteria responsible for a urinary tract infection.
In the meantime, to avoid leaving the victims of these infections to their suffering – we're talking about intense burning sensations and abdominal and pelvic heaviness accompanied by a constant urge to urinate – doctors prescribe, blindly, a broad-spectrum antibiotic, hoping for the best outcome.
The bacterium E. coli is one of the main causes of urinary tract infections in humans. In the image, E. coli bacteria (in pink) attached to a mouse's bladder (in blue) are being attacked by white blood cells (in yellow).
Valerie O'Brien, Matthew Joens, Scott J. Hultgren, James A.J. Fitzpatrick, Washington University, St. Louis
"Not only is this approach unlikely to be effective against the pathogen, but it is also known to promote the emergence of antibiotic-resistant bacterial strains," argues
Arnaud Droit, professor at the Faculty of Medicine at Laval University and researcher at the CHU de Québec - Laval University Research Center.
For the past several years, Professor Droit and his team have been working on developing a test that would allow the bacteria responsible for a urinary tract infection to be identified more quickly, and consequently prescribe the appropriate antibiotic without delay. Their approach, described in a paper recently published in the journal
Molecular & Cellular Proteomics, combines proteomics and artificial intelligence.
Their work focused on 15 species of bacteria that cause 84% of all urinary tract infections. Using a mass spectrometer, the team quantified the abundance of 82 peptides (protein fragments) for each species, effectively defining a specific signature for each. By comparing these signatures with those of bacteria present in a patient's urine sample, it is possible to identify the bacterium responsible for their urinary tract infection. "With this approach, the time required to identify the bacteria in question is less than four hours," states Professor Droit.
The research team tested the reliability of this rapid test on 70 individuals with urinary tract infections. The diagnoses produced using the rapid test were compared with those obtained through the method currently employed in Quebec. "The results match in 87% of cases. This performance would be high enough to consider using the rapid test in clinical settings," estimates Professor Droit. "Moreover, its effectiveness could be improved by adding more peptides to each bacterium's signature."
The next step is to transition this method from the research lab to clinical use. "We developed this test using research instruments that are not available in clinics and hospitals," emphasizes Professor Droit. "We are collaborating with a scientific instrumentation company to adapt the method to simplified versions of these instruments for clinical use."
The other authors of
the study published in Molecular & Cellular Proteomics are Clarisse Gotti, Florence Roux-Dalvai, Ève Bérubé, Antoine Lacombe-Rastoll, Mickaël Leclercq, Maurice Boissinot, and Michel G. Bergeron from Laval University, and Cristina C. Jacob, Claudia Martins, and Neloni R. Wijeratne from Thermo Fisher Scientific in San Jose, California.