When an elderly person experiences new symptoms of confusion, loss of appetite, or smelly urine, patients and families often ask whether they can be due to a urinary tract infection or UTI. After all, UTIs are a common problem among the elderly and it’s easy for doctors to get a urine sample to make the diagnosis.
Unfortunately, misperceptions about UTIs among the elderly are pervasive across health care. A positive urine culture is often equated with the presence of a UTI but the truth is that a positive urine culture is an expected finding among the elderly and does not necessarily mean an infection.
If you were to randomly test all seniors, up to half would test positive for bacteria in the urine — regardless of whether they felt sick or had any symptoms.
More importantly, not all positive urine cultures are bad. New and emerging research suggests that bacteria in the urine can be protective against developing urinary infection by competing with other bacteria for nutrients (https://academic.oup.com/cid/article-abstract/65/10/1745/3978076?redirectedFrom=fulltext). Treating these good bacteria can even increase the chance of developing an actual UTI with all the usual painful and uncomfortable urinary symptoms (https://academic.oup.com/cid/article/55/6/771/345001).
But this new research has yet to reach all health-care providers. Antibiotics are often prescribed to treat the positive urine cultures of elderly patients even though they lack specific symptoms of a UTI. It’s an easy go-to diagnosis even when the problem may be more complex.
As a physician who cares for elderly patients, diagnosing seniors is anything but simple because of their multiple symptoms, health problems and medications. It’s even possible that last time they received an antibiotic for something similar, they got better. While these events can lead us to infer that the antibiotics were effective, more often than not, the illness would have run its course regardless.
Take the symptom of confusion among elderly patients. This is more likely to be related to dehydration, constipation, side effects of medications or other infections, rather than a UTI (https://www.publichealthontario.ca/en/BrowseByTopic/IPAC/Documents/UTI_Delirium_Mental_Status.pdf). A lot of health-care providers appreciate this, but once patients have a positive urine culture they find it hard to understand why they should not treat the bacteria found in the urine with antibiotics.
Many family members think the same way: what’s the downside of treating for possible UTI, just in case? Isn’t it better to be “safe” and give a course of antibiotics?
The reality is that antibiotics have their own set of complications. In my practice as an infectious disease physician, I see patients who develop severe allergic reactions or antibiotic-related diarrhea, both of which can be fatal in older adults. These outcomes are tragic, especially when the patients never needed the antibiotic to begin with.
Another harm: not only do antibiotics kill good bacteria that might protect against infection, they also select for the bad ones that are more difficult to treat. In my practice, when an infection arises in a patient who has already received frequent antibiotic courses, treatment options can be quite limited. Think of antibiotics like a game of cards where the goal is to keep some options in your hand for when you need to play them. This strategy is important for all of us to keep in mind when we decide whether or not antibiotics are the answer.
I encourage family members of elderly patients to ask these three important questions to their health-care provider to reduce unnecessary testing and treatment: