Overprescribing antibiotics for asymptomatic bacteriuria in older adults: a case series review of admissions in two UK hospitals

Abstract

Background Overdiagnosis and overtreatment of urinary tract infection (UTI) with antibiotics is a concern. In older adults, diagnosis of UTI using near-patient urine tests (reagent strip tests, dipsticks) is advised against because the age-related increase in asymptomatic bacteriuria can cause false-positive results. Instead, UTI diagnosis should be based on a full clinical assessment. Previous research lacks systematic information on urine dipstick use in hospitals. The aim of this study was to examine the use of urine dipstick tests and microbiology among older adult hospital admissions in relation to recommended UTI diagnostic criteria. A further aim was to assess factors associated with the use of dipsticks. Methods A case series review of patients aged ≥70 years admitted to two NHS Trust hospitals in England. Records from 312 patients admitted in 2015 meeting inclusion criteria were selected at random. Results Of 298 complete patient records, 54% had at least one urine dipstick test recorded. 13% (21/161) of patients who received a urine dipstick test were diagnosed as having a UTI, only 2 out of these 21 cases had two or more clinical signs and symptoms. 60 patients received a second dipstick test, leading to 13 additional cases of UTI diagnosis. Dipstick tests were more likely to be performed on patients with a history of falls (OR 1.93, 95% CI:1.21, 3.07, p < 0.01), and less likely on those with dementia (OR 0.44, 95% CI: 0.22, 0.87, p < 0.05). The most common reason for testing was routine admissions policy (49.1% of cases), but these cases were predominantly in one hospital. Conclusions Use of urine dipstick tests was high among older adults admitted to hospitals. Most cases were asymptomatic and therefore received inappropriate antibiotic therapy. This paper highlights the need to implement new Public Health England diagnostic guidelines to hospital admission and emergency departments.

Gaps in communication between different staff groups and older adult patients foster unnecessary antibiotic prescribing for urinary tract infections in hospitals: a qualitative translation approach

“…However, the dipstick results made available by the nurses guided doctors’ prescribing decisions. These findings indicate widespread inappropriate use of dipsticks to diagnose UTIs in older adults, which was also found in our parallel case series review [9] and that was not sufficiently addressed by hospital policies or education of clinicians, particularly nurses. However, the findings also suggest poor communication between nurses, doctors and patients on use and interpretation of urinary dipsticks, which fostered inappropriate diagnosis and antibiotic prescribing.…”

“…Clinicians typically focused on vague, observable signs of UTI, and based on patient accounts clinicians could overlook patients’ lack of symptoms of dysuria. Diagnosis of UTIs in older adult should primarily be based on symptoms [1], and research, including our parallel case series review, has consistently found that UTI diagnosis is often not based on appropriate symptoms [5–7, 9]. Our findings suggest that efforts to improve antibiotic prescribing for UTIs could be importantly enhanced by developing advice for clinicians on how to not only recognise but also communicate with older adult patients about symptoms.…”

“…The second gap in communication identified was between nurses, doctors and patients, who interpreted urinary dipsticks differently. Our parallel case series review found that 54% of older adult patients had a urinary dipstick recorded [9], and qualitative and quantitative research in care homes and hospitals have reported clinicians to overrely on positive urinalysis in diagnosing UTIs, fuelling antibiotic prescribing for asymptomatic bacteriuria [4–7, 9]. These findings underline the importance of raising clinicians’ awareness of the unreliability of dipsticks in diagnosing older adults.…”

“…However, healthcare staff was not aware of the downstream implications of problems in urine collection. Our case series review showed that 38% of urine cultures for older adults were mixed growth [9]. Our qualitative findings indicated that junior doctors were often uncertain of how to interpret mixed growth results and could interpret them as requiring broad spectrum antibiotics.…”

“…Interviews with junior doctors found that antibiotic overprescribing was driven by overreliance on laboratory results, fear of poor outcomes, perceived pressure from peers and patients, and difficulties in interpreting symptoms [7]. Qualitative study on hospital clinicians found that misdiagnosis of UTIs was driven by unreflective use of urinary dipsticks [8], and our parallel case series review of patient records also found that 54% of older adults had a dipstick recorded [9]. A survey of junior doctors reported that a third were unaware of antibiotics not being indicated for ASB, but 46% of doctors, who were aware of recommendations, reported still prescribing for ASB [6].…”