When I was asked to write a short piece on urinary tract infections (UTIs) for BSAC, my first response was ‘no problem’. As a clinical microbiologist, I have had a specialist interest in urological infections since early in my training and have contributed to various local and national guidelines on the topic. But when I started to put pen-to-paper, it became clear to me that UTIs really are a contentious topic – for microbiologists, clinicians, policy-makers, and patients.

After decades of neglect, concern about antimicrobial resistance (AMR) has finally forced the spotlight onto this common infection, and the state of play is not pretty. Despite affecting ~50% of women, causing significant physical, psychological and economic burden, and being the leading source of bacterial bloodstream infections, UTI has a reputation for being an uninteresting and unimportant area of infectious diseases^1,

Current diagnostic tests have not significantly changed in the last five decades; when other areas of microbiology have undergone (or are now undergoing) some degree of molecular transformation, routine urinary diagnostics have changed little since my mum was a micro lab technician in the 70s. The myth that urine is sterile is still pervasive amongst both clinical and laboratory professionals at all levels, despite the strength of evidence for the presence and importance of the urinary microbiome^2,3,4. Discounting culture results due to the presence of ‘mixed growth’ or ‘epithelial cells’ are other practices that require critical review and challenge^5,6. The clinical entity of ‘chronic UTI’ is not widely understood or accepted, although there is some growing recognition in the scientific community of the uncertainty surrounding an underlying infective aetiology of chronic urinary symptoms⁷. And in the pipeline, the majority of new diagnostics currently in development are hampered by a requirement to validate new methodologies against a ‘gold-standard’ definition of significant bacteriuria^8,9.

The fact that 25-50% of women with infective urinary symptoms have negative urine cultures (when compared to the current accepted definition) exemplifies the size of the clinical need gap in urinary diagnostics^10,11. Misinterpretation of this fact, and of the flaws in current diagnostic tests, may lead clinicians to incorrectly infer that patients with negative cultures do not have infection and uninformed policy-makers may wrongly conclude that any antibiotic prescribing in this context is ‘inappropriate’^12,13. The fine balance of individual patient benefit vs. antimicrobial stewardship hinges on access to timely and clinically-validated diagnostics. In the absence of these, clinical guidelines can support, but not define, appropriate treatment. A wise colleague recently commented that “guidelines are helpful 80% of the time…the rest of the time you have to think”. Patients’ experiences of being prescribed repeated short courses of antibiotics for protracted or relapsing symptoms is an example of how the presence of a clinical guideline, against a backdrop of incentives for reduced antibiotic prescribing, can negatively impact the care of “the 20%” whose clinical picture doesn’t “fit” the guidelines. There has been commentary and debate on whether antimicrobial stewardship interventions may be contributing to the rise in patients with chronic urinary tract conditions seen in the NHS.¹⁴

At the other end of the spectrum, frequent inappropriate and reflexive urine cultures in older frail adults triggers much antibiotic prescribing bringing with it associated harms, again driven (at least in part) by the old adage that urine is sterile so every positive culture requires treatment^15,16. ‘UTI’ seems to be a condition where many patients who won’t benefit from antibiotics get them, and many patients who would benefit from antibiotics, don’t get them; in other words, a recipe for both antimicrobial resistance and patient suffering.

So how do we do better? I don’t have the answers, but I am willing to ask the question ‘is the current status quo with UTIs good enough?’ and I believe the answer is a resounding ‘no’. The importance of questioning embedded clinical practice that is handed down within specialties over the decades, evaluating new evidence as it becomes available, acknowledging the gaps in evidence and evidence-based guidelines, and importantly hearing patients’ experiences, can only be beneficial in moving patient care forward. Engaging with diagnostics developers is also crucial to ensure the technology in development will meet both the clinical needs of patients and the wider societal need to support appropriate antibiotic use. But firstly, changing the conversation from “it’s just a UTI” to “UTIs matter” would be a positive step forward.

Interested in exploring this topic further? Dr Annie Joseph is chairing our upcoming Infection Clinical Dilemmas webinar: Complex Urinary Tract Infections. Taking place, 22 September 2021, 1630-1800hrs BST, this free event will feature clinical case presentations and lively panel discussion – absolutely not to be missed! Book your place here.

References

1. An introduction to the epidemiology and burden of urinary tract infections (nih.gov)
2. Advances in Understanding the Human Urinary Microbiome and Its Potential Role in Urinary Tract Infection | mBio (asm.org)
3. The Urinary Tract Microbiome in Health and Disease
4. Urobiome updates: advances in urinary microbiome research | Nature Reviews Urology
5. A revalidation and critique of assumptions about urinary sample collection methods, specimen quality and contamination | SpringerLink
6. Increased human pathogenic potential of Escherichia coli from polymicrobial urinary tract infections in comparison to isolates from monomicrobial culture samples | Microbiology Society (microbiologyresearch.org)
7. http://cutic.co.uk/wp-content/uploads/2019/10/BAUS-Statement-on-UTIs-October-2019-1.pdf
8. https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwillZuhwuzyAhUPYcAKHYsZAhkQFnoECBYQAQ&url=https%3A%2F%2Furoweb.org%2Fwp-content%2Fuploads%2F19-Urological-infections_LR.pdf&usg=AOvVaw0rdvwOARPT_Ht9S-FeKvgH
9. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/770688/B_41i8.7.pdf
10. Causes of the Acute Urethral Syndrome in Women | NEJM
11. Women with symptoms of a urinary tract infection but a negative urine culture: PCR-based quantification of Escherichia coli suggests infection in most cases – PubMed (nih.gov)
12. Reducing overprescribing of antibiotics for suspected urinary tract infections in a health sciences campus student health service – PubMed (nih.gov)
13. Use of diagnostic tests and the appropriateness of the treatment decision in patients with suspected urinary tract infection in primary care in Denmark – observational study | BMC Family Practice | Full Text (biomedcentral.com)
14. Rise in persistent UTIs could be linked to antibiotics crackdown | Health | The Guardian
15. Why are antibiotics prescribed for asymptomatic bacteriuria in institutionalized elderly people?: A qualitative study of physicians’ and nurses’ perceptions | CMAJ
16. “Urinary Tract Infection”—Requiem for a Heavyweight – Finucane – 2017 – Journal of the American Geriatrics Society – Wiley Online Library