Standard Testing Frequently Misses UTIs — But Now We Have a Better Way
Have you ever had a burning sensation when you urinate? Low fever, back pain, and maybe cloudy urine? Male or female, it could have been a urinary tract infection. If it lasted long enough, the chances are good you went to the doctor for help. For about 20% of women, standard testing for a UTI does not reveal the presence of infection-causing bacteria, even though bacteria may be causing their symptoms. Well, a new test may provide better answers.
Research published in Clinical Microbiology and Infection explored a more sensitive test for detecting by-products of bacteria, like Escherichia coli and Staphloccocus saprophyticus, that are often the culprits behind UTIs.
Bladder infections, also called cystitis, are a common form of UTI. If you do not frequently experience UTIs, your doctor will likely diagnose you based on the results of a urine test and evaluation of your symptoms. The urine sample offers healthcare practitioners a way to detect bacteria that are being shed into your urine from the UTI.
While different microorganisms like fungi and viruses can cause UTI infections, bacteria are the most frequent cause. When your immune system cannot take down the bacteria, you experience symptoms of an infection. When bacteria invade your kidneys, the infection is called pyelonephritis, or an infection of the urethra is called urethritis.
Now imagine you go to the doctor with symptoms like painful urination (called dysuria) and the standard testing shows no bacteria. The attending physician may suggest your symptoms are passing, or worse, that they are not real. You may also be diagnosed with "urethral syndrome," a catch-all, vague disorder for women suffering UTI symptoms who do not show clear results on traditional urine tests.
On average, UTI symptoms account for approximately 5% of doctor visits by women each year. In this study, researchers at the University of Ghent evaluated data from midstream urine samples provided by 308 Belgium women between 17 and 91 years of age. Of these patients, 220 had symptoms of a UTI, while the other 86 did not.
Researchers used two types of tests to evaluate the date. First, slides and samples were sent to a laboratory for incubation and microbiological analysis. Second, urine was also prepared for examination by using quantitative polymerase chain reaction (qPCR) testing, a more recent, more sensitive type of microbiological analysis that is used to detect and identify DNA sequences. In this study, both the standard and qPCR tests targeted for the presence of the two bacteria E. coli and S. saprophyticus.
The standard lab test identifies the presence of bacteria, while qPCR identifies very small quantities of DNA material from bacteria like E. coli to reveal the infection. The side-by-side comparison of samples using the different test methods was telling. Of the 220 symptomatic women, standard testing identified 80.9% as positive for a uropathogen. Correspondingly, using qPCR, 95.9% of the 220 women tested positive for bacteria. In practice, these could mean that the 20 to 30% of women being told they do not have UTIs are actually suffering an infection.
In this study, we used a more sensitive test to look for bacteria that commonly cause UTIs. We found E. coli in nearly all women complaining of symptoms, even if they had a negative traditional urine culture. This suggests that if a woman has these symptoms, she probably does have a UTI.
Based on these results, Heytens, a general practitioner and researcher, believes that it could be unnecessary to test women complaining of non-complicated UTIs, because it is overwhelmingly likely bacteria are present. "What we don't yet know is whether all women with these symptoms would benefit from a course of antibiotics," he added, which is the standard treatment for a UTI.
If you suffer symptoms of a UTI and are told it is all in your head — think again and consider a second opinion.