When I first started my medical education, I was told to always test for UTI in older adults with falls, delirium or any other vague complaints. I ended up treating a lot of positive urinanalysis. Then, the phenomenon of antibiotic resistance emerged and the rationalisation of antibiotic use was becoming the new standard of practice. We are told now that unless there are symptoms or UTI, a positive urinanalysis in elderly is called asymptomatic bacteruria and does not need antibiotic treatment. Is that really a hard fact?
I started to search the literature on the subject, I asked a few emerg doctors, and finally a geriatrician was consulted. Here is a summary of my findings.
First, let’s list some facts together.
Elderly are at increased risk for urinary tract infections. The age-associated immunity change, post-menopausal, incontinence, urinary retention, diabetes and long term care/hospital stays are all risk factor (1).
The prevalence of asymptomatic bacteriuria (ASB) increases with age. In elderly men in the community, it can reach 5-6% and in women, 15% to 20%. In institutionalized elderly, the prevalence of ASB in men is 15-35% and 30-50% in women (2). This small review on the subject was done and it showed that empirically testing and treating for UTI in ASB population increase resistance and has no effect on mortality and morbidity (2).
Symptoms of UTI like we all know are burning sensation, increased frequency, sensation of incomplete voiding, supra-pubic tenderness, hematuria. In elderly, you might want to add a few more: increased incontinence, vague abdominal pain, and lower back pain, even change in mental status (3).
I found this interesting systematic review about UTI and neuropsychiatric disorder in elderly (4). It stated that about 88% of studies found on the subject revealed a positive association with the presence of UTI and neuropsychiatric exacerbation (Dementia, delirium, affective disorder).
Another controversy about UTI in elderly is the diagnosis. Dipstick detection does not seem to be accurate and shows false positive in about 30% in long term care (LTC) patient (5). Our gold standard in pediatric and adult population is the culture. But guess what? In LTC elderly 15% of positive culture might not be a UTI in the absence of specific symptoms (6).
Is it clearer? NO, it is more confusing!
- UTI is the most frequent infection in elderly.
- Long-term care patient are at increased risk of UTI.
- Healthy non-demented elderly from the community can be evaluated almost the same as an adult.
- Also, be aware that your patient in delirium or demented patient, they may not express specifics GU symptoms. But if they are in the emergency department, it is because there is something different/wrong with them. What is it? Fever? Confusion? Vague abdominal pain? Increased incontinence? Constipation? A very detailed history with the patient and proxies will help you decide if you should test or no for UTI.
The antibiotic of choice? It depends on your local resistance. But this is the easiest part of UTI and fortunately, E. coli is the most frequent pathogen isolated (followed by Proteus, Klebsiella, Enterococcus).
The only thing that I will add about antibiotics is that the Beers criteria that we talked about earlier in the summer advised us to be careful with Nitrofurantoin use in elderly.
I hope this will help you!
- Detweiler K, Mayers D, Fletcher SG. Bacteruria and Urinary Tract Infections in the Elderly. The Urologic clinics of North America. 2015 Nov;42(4):561-8. PubMed PMID: 26475952.
- Ariathianto Y. Asymptomatic bacteriuria – prevalence in the elderly population. Australian family physician. 2011 Oct;40(10):805-9. PubMed PMID: 22003486.
- Rowe TA, Juthani-Mehta M. Diagnosis and management of urinary tract infection in older adults. Infectious disease clinics of North America. 2014 Mar;28(1):75-89. PubMed PMID: 24484576. Pubmed Central PMCID: 4079031.
- Chae JH, Miller BJ. Beyond Urinary Tract Infections (UTIs) and Delirium: A Systematic Review of UTIs and Neuropsychiatric Disorders. Journal of psychiatric practice. 2015 Nov;21(6):402-11. PubMed PMID: 26554322.
- Arinzon Z, Peisakh A, Shuval I, Shabat S, Berner YN. Detection of urinary tract infection (UTI) in long-term care setting: Is the multireagent strip an adequate diagnostic tool? Archives of gerontology and geriatrics. 2009 Mar-Apr;48(2):227-31. PubMed PMID: 18314207.
- Ducharme J, Neilson S, Ginn JL. Can urine cultures and reagent test strips be used to diagnose urinary tract infection in elderly emergency department patients without focal urinary symptoms? Cjem. 2007 Mar;9(2):87-92. PubMed PMID: 17391578.