Treating UTIs in aged care residents

Australia has high levels of antibiotic usage compared to similar high income countries and antimicrobial resistance is now a significant issue for healthcare workers and their patients(1). Urinary tract infections (UTI) are the most common indication for antibiotics in nursing homes and whilst they are mainly used to treat cystitis, they are often used for asymptomatic bacteriuria (ASB) and pyelonephritis(2).

The 2017 Aged Care National Antimicrobial Prescribing Survey (acNAPS) found continuing high rates of inappropriate antimicrobial use in aged care homes(2), presenting an opportunity for all health care professionals to use antimicrobial stewardship practices to optimise antimicrobial usage in nursing homes(1). Furthermore, addressing antimicrobial usage in nursing homes will contribute to an overall reduction of antimicrobials within Australia and reduce the risk of antibiotic resistance.

An Australian study in 2012 showed that nursing home patients >65 years were more likely to be resistant to commonly used antibiotics for UTI compared to community patients, for example, resistance to trimethoprim was 29.6% versus 16.2%, amoxycillin/clavulanate was 27.1% versus 19.8% and multi-drug resistant Enterobacteriaceae was 12.4% versus 6.1% in nursing home patients compared to in community patients respectively(3).

Incorrect diagnosis of UTI in aged care facilities is also a common finding, with a 2018 report from Australia showing only 7 of 119 diagnosed UTI met appropriate definitions(4). The McGeer et al definition for UTI in aged care facilities was updated in 2012 and requires patients to have both bacteria present in their urine as well as signs or symptoms of UTI such as fever or acute dysuria(5).

Although ASB is highly prevalent in nursing home residents with or without specific or non-specific symptoms(6), it is not recommended to screen for or treat ASB in these patients(7). Even in the presence of ASB, patients with functional or cognitive impairment who experience falls or increased delirium without signs of infections should be investigated for causes other than infection(7). Whilst giving antibiotics for ASB does lead to a bacteriological cure, it does not reduce symptomatic UTI, complications or death(8).

Typical bacteria in nursing home patients include Enterobacteriaceae (such as Escherichia Coli, Proteus or Klebsiella), Pseudomonas and Enterococcus species. Compared with community patients, nursing home residents are more likely to be colonised with Proteus or Pseudomonas(3).

Empirical treatment for cystitis includes trimethoprim 300mg daily, cephalexin 500mg every 12 hours, amoxycillin/clavulanate 500/125mg every 12 hours, nitrofurantoin 100mg every 12 hours(9). Nitrofurantoin should be used with caution in elderly patients as renal impairment may reduce its effectiveness and increase risks of toxicity(9).

If bacteria is likely to be resistant to these antibiotics, use norfloxacin 400mg every 12 hours(9). Guidelines recommend treating women with 3-5 day courses and men with 7-day courses of antibiotics for cystitis(9). Treatment of acute pyelonephritis requires amoxycillin/clavulanate 875/125mg every 12 hours, cephalexin 500mg every six hours or trimethoprim 300mg for 10-14 days(9). If bacteria is likely to be resistant to the above drugs, it is recommended to use norfloxacin 400mg or ciprofloxacin 500mg every 12 hours for 7 days(9). Choice of antibiotics may be driven by the patient’s history, patient’s allergies or local susceptibility patterns.

To further optimise antimicrobial therapy in nursing home patients, it is recommended that all antibiotics for infections are documented with the indication and a review or stop date for the antibiotics(2).

Other strategies include educating staff, residents and their families about appropriate antimicrobial usage and following infection control guidelines. Pharmacies delivering services to RACF can provide their RACF with a National Prescribing Service (NPS) Medicinewise Report if they use the Webstercare® program. This process involves the pharmacy completing an audit of antibiotic usage for UTI in the RACF. The Medicinewise Report provides feedback to the RACF about their antibiotic usage for UTI and how it compares to other RACF.

References