When should I consider treating my hospitalized patients with asymptomatic bacteruria (ASB)?

The great majority of hospitalized patients with ASB do not need treatment with antibiotics.

In fact, there are only a couple of conditions for which treatment of ASB is indicated:  pregnant women (due to risk of pyelonephritis and low-birth infants/pre-term delivery) and before  GU instrumentation, such as transurethral resection of the prostate or other GU procedures for which mucosal bleeding is anticipated (1).  

So for the great majority of our hospitalized patients, including the elderly, diabetic women, institutionalized residents of long-term facilities, and spinal cord injury patients treatment of ASB is not indicated.  Even in the case of renal transplant patients, supportive evidence for the  use of prophylactic antibiotics in ASB is so far lacking (2).  

The estimated prevalence of ASB varies widely in the population,  with rates of 15-20% among community-dwelling women > 70 yrs of age, and 5-10% for men>65 yrs for community-dwelling men. In long-term care facility residents, 25-50% of women, 15-40% of men, and 100% of those with chronic indwelling catheters have ASB (3).  

So keep these rates in mind before attributing patient’s symptoms to ASB (ie, patient’s presentation may have nothing to do with urine findings).  It’s also worth emphasizing that pyuria accompanying ASB is not an indication for treatment.

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1. Nicolle LE, Bradley S, Colgan R, et al. Infectious Diseases Society of America guidelines for the diagnosis and treatment of asymptomatic bacteriuria in adults. Clin Infect Dis 2005;40:643-54.  https://academic.oup.com/cid/article/40/5/643/363229

2. Coussement J, Abramowicz D. Should we treat asymptomatic bacteriuria after renal transplantation? Nephrol Dial Transplant 2013;0:1-3. https://academic.oup.com/ndt/article/29/2/260/1913512

3. Nicolle LE. Asymptomatic bacteriuria in older adults. Geriatrics & Aging 2003;6:24-28. https://www.healthplexus.net/files/content/2003/October/0609bacteriuria.pdf

When should I consider treating my hospitalized patients with asymptomatic bacteruria (ASB)?

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