The Top UTI Myths
Schultz L et al. Top Ten Myths Regarding the Diagnosis and Treatment of Urinary Tract Infections. J Emerg Med 2016. PMID: 27066953
Data suggests that emergency department (ED) providers are over-diagnosing urinary tract infections (UTI), leading to improper use of antibiotics. UTIs are the most common type of infection in the United States and are often diagnosed in the ED. Data from the CDC suggests that antibiotics could have been avoided in about 39% of UTI cases. This article addresses some of the reasons behind this phenomenon and proposes that common “myths” about how to diagnose and treat UTIs are pervasive in emergency medicine, despite convincing literature debunking their validity.
This is a review article out of the University of Wisconsin – lead author is a pharmacist, secondary authors are MDs. They review the literature in the framework of 10 “myths” associated with the diagnosis and treatments and offer guidance in clinical scenarios.
Myth 1: The Urine is Cloudy and Smells Bad. My Patient has a UTI
Myth 2: The Urine has Bacteria Present. My Patient has a UTI.
Myth 3: My Patient’s Urine Sample has >5 Squamous Epithelial Cells per Low Power Field and the Culture is Positive. Because the Culture is Positive, I can Disregard the Epithelial Cell Count and Treat the UTI.
Myth 4: The Urine has Positive Leukocyte Esterase. My Patient Should Have a Urine Culture Performed, Has a UTI, and Needs Antibiotics.
Myth 5: My Patient Has Pyuria. They must have a UTI.
Myth 6: The Urine Has Nitrites Present. My Patient has a UTI.
Myth 7: All Findings of Bacteria in a Catheterized Urine Sample Should Be Diagnosed as a UTI.
Myth 8: Patients with Bacteriuria Will Progress to a UTI and Should Therefore Be Treated.
Myth 9: Falls and Acute Altered Mental Status Changes in the Elderly Patient Are Usually Caused by UTI.
Myth 10: The Presence of Yeast or Candida in the Urine, Especially in Patients with Indwelling Urinary Catheters, Indicates a Candida UTI and Needs to Be Treated.
The most important factor to consider when diagnosing a UTI is whether or not the patient has appropriate symptoms. UTI is not a diagnosis made in the lab (or by visually inspecting the urine). Asymptomatic bacteriuria is very common, increasingly so in older patients, and has not been associated with long-term negative outcomes. Pyuria is common in noninfectious conditions such as acute renal failure or dehydration. Thus, the presence of bacteria or pyuria in either a dip, urinalysis, OR culture in the absence of symptoms does not mean the patient has a UTI and does not warrant treatment, except in very specific scenarios. The most reliable indicator of UTI on urine dip is the presence of urine nitrates, but symptoms should be present before treatment is started.
Providers should keep in mind that every patient with an indwelling Foley catheter for more than 2 weeks will be colonized with bacteria. These patients should also only be treated if symptomatic – overuse of antibiotics in these patients, in particular, will ultimately select for resistant organisms.
Be cautious when diagnosing elderly patients with acute mental status changes found to have bacteriuria and/or pyuria with a UTI and stopping there – these patients may have several reasons for their mental status change and diagnosis of UTI should only be made after other causes are thoroughly investigated. In hemodynamically stable patients, it is appropriate to withhold antibiotics until a more in-depth work up has been performed.
The Bottom Line:
This is a well-done review article that creatively frames the literature in the context of common dogma surrounding UTI diagnosis and treatment. The literature is convincing and comprehensive; we over-diagnose UTIs and should be very cautious in the absence of symptoms. While the authors offer general points for guidance, it would have been helpful to see a more specific algorithm or clinical guideline (when to culture, etc) – however given the difference in practices between instructions this is no easy feat.