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IPAC News: Featured News


Asymptomatic Bacteriuria: An Overview

What is asymptomatic bacteriuria?

Asymptomatic bacteriuria is the presence of bacteria in the urine without the signs and symptoms of a urinary tract infection (UTI). This occurs in 15 to 30 per cent of male and 25 to 50 per cent of female long-term care residents, 65 years of age or older. In these residents, bacteria have become part of the resident’s normal flora and do not indicate an infection.

Why is asymptomatic bacteriuria a problem?

Confirmed UTIs are the most common infection in long-term care settings, and are the most frequent cause for the use of antibiotics (Partners for Appropriate Anti-infective Community Therapy, 2013). However, nonspecific signs such as behaviour change or cloudy, smelly urine are often mistaken for symptoms of a UTI. Clinical assessment of the elderly for specific signs and symptoms of a UTI can be challenging, and cognitive or functional impairment can add to the difficulties. These factors, along with an incomplete understanding of asymptomatic bacteriuria and difficulty interpreting and understanding urine culture results, result in the overuse of antibiotics to treat UTIs in long-term care.

According to the most frequently referenced study,  Loeb et al (2005), one third of prescriptions for presumed UTIs in long-term care residents are for asymptomatic bacteriuria. Unnecessary use of antibiotics in these populations can lead to serious consequences, including allergic reactions, drug interactions, and the development of antibiotic resistance. Routine screening for UTIs in asymptomatic residents is not necessary and  treatment not required.

What should be done for asymptomatic bacteriuria?

Nothing. Understand that bacteria have become part of the resident’s normal flora, and are not indicative of an infection. Do not send a urine specimen for culture and sensitivity, and do not treat asymptomatic residents.

The Loeb et al (2005) study, conducted in 24 long-term care homes in Ontario and Idaho by Dr. Mark Loeb and a prestigious group of researchers, including Dr. Allison McGeer and Dr. Dick Zoutman, concluded that “in the absence of a minimum set of symptoms or signs of urinary tract infection, urine should not be cultured and antimicrobials should not be prescribed.” The Infectious Disease Society of America guidelines published by Dr. Lindsay Nicolle et al indicated that asymptomatic bacteriuria has not been shown to be harmful in most adult populations, and treatment in the absence of defined signs and symptoms should be discouraged.

Other IPAC news articles:

What are the signs and symptoms of a urinary tract infection?

Management of UTIs in Long-Term Care



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Page last updated: 2014-06-02 1:59 PM
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