Better Health While Aging

Practical information for aging health & family caregivers

UTIs and Urine Bacteria in Aging:
How to get the right diagnosis & avoid unneeded antibiotics

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Depositphotos_40397787_m-2015-urine-testing-compressorQ: An older friend, who is in her 90s, has been having bacteria in her urine, but no symptoms. Despite treatment with antibiotics, she was still having bacteria in the urine, so the doctor recommended chronic antibiotics and a referral to urology.

What can be done when an elderly woman has bacteria in her urine but no symptoms? Can a urology consultation help?

A: This is a great question. People often think that your friend is having a “recurring urinary tract infection (UTI)” or even a chronic UTI. But actually, you are describing something called asymptomatic bacteriuria, which means having urine bacteria without symptoms.

Every older person and family caregiver should know about asymptomatic bacteriuria. Here’s why:

  • It’s very common in older adults. This condition is found in an estimated 20% of women aged 80 or older, and also affects older men. The older the person, the more common it is. Asymptomatic bacteriuria is even more common in nursing homes, where it’s estimated to affect 30-50% of residents.
  • It’s often confused with a urinary tract infection (UTI).  This can lead to unnecessary — and potentially harmful — treatment with antibiotics.
  • It usually does NOT need to be treated with antibiotics. As I’ll explain below, research shows that people don’t live better or longer when asymptomatic bacteriuria is treated. In fact, such treatment can be harmful: one study found that treatment increased the risk of future (real) UTIs, and increased the risk of infection with antibiotic-resistant bacteria.

  • It’s common for older adults to inappropriately be given antibiotics to treat this condition. Part of why this happens is that distinguishing this condition from a real UTI cannot just be done with a urine test. Instead, health providers must take the time to talk to the patient — or family caregiver — and ask about whether symptoms are present. In a busy clinical environment, this step is all-too-often neglected.

In short, this is another one of those common aging health issues that can easily be mismanaged, unless older adults and family caregivers know to ask extra questions.

Because it’s so common for antibiotics to be inappropriately prescribed for this condition, “Don’t treat asymptomatic bacteriuria with antibiotics” is the number one “Choosing Wisely” recommendation from the Infectious Disease Society of America. The American Geriatrics Society also includes this recommendation on its Choosing Wisely list.

Now, let’s try to equip you to understand this common condition. This will help you — and your older loved ones — avoid unnecessary testing and antibiotic treatment. Specifically, in this article I’ll cover:

  • What is asymptomatic bacteriuria?
  • How common is asymptomatic bacteriuria?
  • How to tell the difference between asymptomatic bacteriuria and a UTI
  • Why asymptomatic bacteriuria usually doesn’t warrant antibiotics

I’ll close with some practical tips for older adults and family caregivers concerned about UTIs and/or bacteria in the urine.

What is asymptomatic bacteriuria?

Asymptomatic bacteriuria means having significant quantities of bacteria in the urine, but no clinical signs of inflammation or infection.

In other words, in asymptomatic bacteriuria, a urine culture will be positive. (This means that if your healthcare provider takes a sample of urine and a clinical laboratory incubates it, within 1-2 days, a sizeable quantity of bacteria will grow.)

When bacteria are present in the bladder but not provoking an inflammatory reaction, this can also be called bacterial “colonization” of the bladder.

How common is asymptomatic bacteriuria?

Asymptomatic bacteriuria is more common in older adults than many people — including practicing clinicians — may realize:

  • In women aged 80 or older, 20% or more may have this condition.
  • In healthy men aged 75 or older, 6-15% have been found to have bacteria with no UTI symptoms.
  • Studies of nursing home residents have found that up to 50% may have asymptomatic bacteriuria.

This condition also affects 2-7% of premenopausal women, and is more common in people with diabetes.

Asymptomatic bacteriuria becomes more common as people get older, in part because it is related to changes in the immune system, which tends to become less vigorous as people age or become frailer.

Studies have found that in older adults, asymptomatic bacteriuria does sometimes go away on its own, but it also often comes back or persists.

How to tell the difference between asymptomatic bacteriuria and a UTI

By definition, in asymptomatic bacteriuria, there should be no UTI symptoms present.

The following signs and symptoms can be caused by UTI:

  • Burning or pain with urination
  • Increased frequency or urgency of urination
  • Bloody urine
  • Pain in the low abdomen, flank, or even back
  • Fever

(What about “cloudy” or “foul-smelling” urine? In the absence of other symptoms, no study has shown that this is a good way to detect a possible UTI. See here: Cloudy, Foul-Smelling Urine Not a Criteria for Diagnosis of Urinary Tract Infection in Older Adults.”)

Whether or not an older person has a clinical UTI, the urine dipstick may be abnormal, in part because certain abnormal results suggestive of UTI may in fact only reflect bacterial colonization of the bladder. So one should not rely on urine dipsticks or related urine analysis tests (which measure the number of white blood cells in the urine, among other things) as the sole justification for diagnosing a UTI. Symptoms are necessary!

The thing is, some older adults may only show vague or non-specific symptoms when they get a UTI, such as confusion or weakness. (That “confusion” would be delirium.) This is especially true of aging adults who are frail, or are quite old, or have Alzheimer’s or another dementia.

For this reason, it can be difficult to determine whether a frail or cognitively impaired older person is having UTI symptoms that warrant treatment.

Experts have debated whether it’s justified to treat for possible UTI, for those cases in which an older person with asymptomatic bacteriuria shows signs of delirium, but no other UTI symptoms.

Why asymptomatic bacteriuria usually doesn’t warrant antibiotics

Clinical studies overwhelmingly find that in most people, treating asymptomatic bacteriuria with antibiotics does not improve health outcomes. Even when it comes to the nursing home population, which is frailer than the general population, a 2022 systematic review found that antibiotic treatment of asymptomatic bacteriuria didn’t improve outcomes.

(The exceptions: pregnant women and men about to undergo urological procedures do benefit from screening for and treatment of asymptomatic bacteriuria.)

A 2015 clinical research study found that treatment of asymptomatic bacteriuria in women was associated with a much higher chance of developing a UTI later on, and that these UTIs were more likely to involve antibiotic-resistant bacteria.

Even when it comes to the nursing home population, which is frailer than the general population, a 2022 systematic review found that antibiotic treatment of asymptomatic bacteriuria didn’t improve outcomes.

Despite the expert consensus that this condition doesn’t warrant antibiotics, inappropriate treatment remains very common. A 2014 review article on this topic noted overtreatment rates of up to 83% in nursing homes. To combat this issue, this 2023 BMJ article outlines an approach nursing homes can take: Reducing unnecessary urine culture testing in residents of long term care facilities.

Is there a role for cranberry to treat or manage urine bacteria?

The use of cranberry juice or extract to prevent UTIs has been promoted by certain advocates over the years, and many patients do prefer a “natural” approach when one is possible.

However, top quality clinical research has not been able to prove that cranberry is effective for this purpose. In a 2016 study of older women in nursing homes, half were given cranberry capsules daily. But this made no difference in the amount of bacteria or white blood cells in their urine.

In a related editorial titled “Cranberry for the Prevention of Urinary Tract Infection? Time to Move On,” which summarized many other studies of cranberry for the prevention of UTI, the author concluded:

The evidence is convincing that cranberry products should not be recommended as a medical intervention for the prevention of UTI. A person may, of course, choose to use cranberry juice or capsules for whatever reason she or he wishes. However, clinicians should not be promoting cranberry use by suggesting that there is proven, or even possible, benefit. Clinicians who encourage such use are doing their patients a disservice.”

A 2012 systematic review of high-quality research studies of cranberry for UTI prevention also concluded that cranberry products did not appear to be effective.

That said, many people really feel that cranberry supplements make a difference.

As cranberry is unlikely to cause harm to older adults, I don’t object when an older person or family caregiver wants to use them. But I don’t particularly encourage it either.

Practical tips on urine bacteria and possible UTIs in older adults

Given all this, what should you do if you are worried about bacteria in the urine, or a possible UTI?

Here are my tips for older adults and families:

  • Realize that asymptomatic bacteriuria is common in older adults.
    • If you keep having positive urine cultures despite feeling fine, you may have asymptomatic bacteriuria.
  • Know that treatment of asymptomatic bacteriuria is not going to help, and might lead to harm.
    • Unless you are having symptoms, it’s pointless to try to “eradicate” bacteria from the bladder. Studies show that this increases your risk of getting a real UTI later on, and that you’ll be more likely to be infected with bacteria that are resistant to antibiotics.
    • Antibiotic treatment also affects the “good bacteria” in your gut and elsewhere in the body. Research to help us understand the role of the body’s usual bacteria (the “microbiota”) is ongoing, but suggests there can be real downsides to disrupting the body’s bacteria. So you don’t want to use antibiotics unless there’s a good reason to do so.
  • Avoid getting a urine culture unless you’re experiencing symptoms of likely UTI, such as pain with urination or low belly pain.
    • Some healthcare providers will do a urine culture “just to check” for UTI. Or sometimes patients and family members request this. But this is a bad idea, since all you might do is uncover signs of asymptomatic bacteriuria (which then has a tendency to be inappropriately treated with antibiotics).
    • Experts strongly recommend that urine tests for possible UTI only be done if an older person is experiencing symptoms.
    • If a health provider suggests a urine test and you aren’t having UTI symptoms, inquire as to the purpose of the test.

If you’re caring for an older adult who has dementia or is otherwise prone to delirium:

  • Realize that it can be tricky to determine whether the person is experiencing UTI symptoms.
    • The doctors should still attempt to do so before checking a urine culture or treating any bacteria found in the urine. Specific symptoms to check for include dysuria (painful urination), fever, and lower belly pain.
  • Realize that some experts believe that increased confusion alone (meaning no fever or other signs of UTI) may not be a good reason to treat a nursing home resident for a presumed UTI.

In short: I’d summarize the benefits and burdens of treating asymptomatic bacteriuria in a 90-year-old woman as follows:

Benefits: No proven benefit to antibiotic treatment in someone who doesn’t have clinical signs of a UTI.

Burdens: Antibiotics cost money, and increase pill burden. There is a risk of side-effects, of interactions with other medications, of harming your body’s “good bacteria,” and of developing an infection resistant to antibiotics. Also, the overuse of antibiotics in society means we are developing more resistant bugs all around us.

So there you have it. If an older person has a positive urine culture but no symptoms, think long and hard before agreeing to treatment. And ask extra questions before spending time pursuing a urology consultation.

Remember, bacteria in the urine does NOT equal a UTI.

So, ask your clinicians if this could be asymptomatic bacteriuria. Tell them you’ve heard that the Infectious Disease Society of America, the American Geriatrics Society, and other experts say that this condition should not be treated in older adults. (Unless you’re about to undergo a urological procedure.)

You can even share these peer-reviewed articles:

This article was first published in 2015. It was reviewed and updated by Dr. Kernisan in February 2024. (The basics about asymptomatic bacteriuria and UTIs in aging adults don’t change much!)

 

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Comments

    • Yes, it seems plausible that urine pH would influence bacterial growth.

      Recurrent UTIs can be challenging to control, especially in people like your mother. Some studies have found that vaginal estrogen cream can help. Good luck!

  2. Thank you for passing this information on to your subscribers Dr. Kernisan. My 94 year old mother is prone to UTI’s and her doctor recently prescribed a course of antibiotics that really did nothing but give mom stomach pains. As her full time 24/7 caregiver I usually try to ply her daily with some cranberry juice. I’m fortunate if my mom takes in 12oz of liquid in a day.
    Question: Would an insufficient daily intake of liquids invite and/or exacerbate UTI’s and asymptomatic bacteriuria?

    • My understanding is that to potentially benefit from cranberry juice, one has to drink quite a lot of it…as in, an amount that isn’t feasible or palatable for most older adults. Hence many studies have tried cranberry extracts instead, but as I mention in the article, it’s not clear that these work well.

      Re your question about dehydration and UTI risk, I addressed this here: How to Prevent, Detect, & Treat Dehydration in Aging Adults.

      Basically, it’s plausible that mild dehydration might increase UTI risk or otherwise impair the body’s ability to repel bacteria. But it hasn’t been proven definitively.

      12 ounces of fluid per day is not very much, and probably not enough for most older adults. There are suggestions in the dehydration article on how to help an older person take in the fluids they need. Good luck!

      • Importance of hydration: About 2 yrs ago, husband was admitted to hospital ER, diagnosed with UTI, antibiotics started. (He wears a nephrostomy.) Next morning (admitted to hospital by then) a physician came into his room, gave 2 family members (myself & son) quite a lecture on the trend toward treating dehydration rather than antibiotics. Dr. took husband OFF the antibiotics, initiated heavy dehydration methods. He came through successfully. Presently, as his primary caregiver, am focused on ample hydration – water & other fluids. Keep a fresh jug of water in frig for him as a rough measure of fluid intake for the day. It’s just one of a group of procedures I’m using to track & hopefully prevent hospitalizations that may be diagnosed UTI. Has been extremely helpful. I looked over several of the linked studies briefly. Didn’t notice ANY mention of simple hydration as playing a role in prevention.

          • FYI, Husband not diagnosed with either heart failure or edema. However I monitor his receptiveness to fluids and don’t force them – just encourage, provide water & let him drink what he wants. Thank you for the reply.

  3. While you’re at it – why not tell us what generally CAUSES asymp. bac and UTI?

    • Most parts of the human body are frequently exposed to bacteria. Whether the bacteria settle in to “colonize” (i.e. establish a presence without causing significant inflammation and illness), or to “infect” (establish a presence that does cause inflammation or illness) depends on factors related to the specific bacteria in question, as well as on the state of the person and their immune system.

      In fact, scientists are increasingly realizing that whether new bacteria can gain a foothold is partly dependent on the presence and activity of other colonizing bacteria. This may be why using antibiotics can increase the risk of infections later on; antibiotics weaken your “good” or “usual” bacteria, which can make it easier for “new” or potentially “bad” bacteria to settle in.

      • I understand that antibiotics can kill good bacteria. What are you thoughts on pro-biotics for elders? Especially after a course of anti-biopics?

        • The gut microbiome is a very interesting frontier in medicine, however for the time being it’s unclear how to effectively use probiotics to support it. Research is ongoing but I’m not aware of any published research specific to older adults, and given that the immune system changes with aging, it’s quite possible that things will work differently in frail elders compared to healthy middle-aged people. Also, probiotics may end up being something that really needs to be tailored to the individual, regardless of their age.

          A recent study found that probiotics after antibiotics delayed reconstitution of the prior gut microbiome.

          Last but not least, the quality of probiotics in the US is presumably like that of any other supplement; highly variable and so it’s often hard to know just what you are getting.

  4. I mean, is there anything more specific than a general weakening on the immune system as a person ages that would cause this? Or maybe the question should be: How does one go about strengthening the immune system as a person ages? Would regular exercise help, certain changes in diet? Does wearing adult diapers contribute to causes of this problem?

    • The aging of the immune system is called “immunosenescence.” Researchers are currently working to piece together exactly how it happens, and how we might be able to influence this process.
      Causes, consequences, and reversal of immune system aging

      I don’t think anyone knows for sure how to counter or delay immunosenescence. Presumably exercise, enough sleep, a healthy diet, social relationships, and all the other things we know are good for older people can help maintain the immune system. But we don’t yet know of specific regimens proven to work.

      Regarding diapers: people with incontinence are at higher risk for developing UTIs. But this in part will reflect the fact that adults wearing diapers are often older or frailer, which in of itself puts one at risk for developing infections. Otherwise, some studies have suggested that nursing homes with better staffing and better care practices have fewer UTIs among their residents. Presumably keeping someone reasonably clean helps reduce the risk of UTIs.

  6. Mom has dementia and though consistently has bacteria in her urine and dark urine, she is becoming resistant to antibiotics. She frequently has the foul smell and becomes even more confused than she already is. The elderly home where she lives has a geriatric physician. Is there any advantage to taking her to an urologist?

    • Well, as I explain above, chronic bacteria in the urine is quite common in older adults. So the question is, is she showing other signs suggesting a clinically significant UTI. Foul smell probably doesn’t count, but if she definitely gets more confused, that could be a sign of a UTI. She should also at that time be evaluated for other causes of delirium and/or increased confusion. These include constipation, untreated pain, medication side-effects, electrolyte imbalances, other new illness, and much more.

      Regarding the question of a urologist: if you are feeling stuck, then sometimes getting a second opinion from a specialist can help. However, a urologist probably won’t evaluate your mom for other problems that might be causing increased confusion; that is really the job of a generalist or geriatrician.

      So you could try seeing a urologist, but I would also encourage you to ask more questions of the geriatrics physician at her living facility. Good luck!

  7. In your article, you stated that asymptomatic bacteriuria is common in older adults and in women aged 80 or older, 20% or more may have this condition. Last night my son and I were eating dinner at my mom’s house and she started saying that she was having a really hard time using the bathroom. I wonder what older people can do to prevent UTIs.

    • An older woman complaining of a “hard time using the bathroom” does not necessarily sound like a UTI symptom to me. I would encourage you to ask her to elaborate. Is she having pain with urination? Or is she referring to constipation?

      Unfortunately, almost nothing has been proven to prevent UTIs in older adults who are not hospitalized. There is some evidence that remaining mobile helps prevent UTIs.

    • It might be that her toilet is low and it is hard for her to get up. My mother has complained about the a toilet at my house. Maybe a taller toilet or handles near by.

      • Good thought, Ellen. There are also raised toilet seats that can fit onto regular toilets, or frames that go over the toilet so the person doesn’t have to get as low when using it. These can usually be rented before you invest in buying one.

        • Thank you, Dr. Didyk, and the commenter called Ellen. Your responses are the most recent to this article that I can find! Some questions or comments are 5 to 7 years old. I am concerned that the articles I am getting from Dr. Kernisan’s site are not up-to-date and therefore not accurate. I am impressed with her and with her articles in general, but only now am noticing the dates. Also–what is “older”? People are afraid to say “old” because it has become a term of derision for many, and just a negative assessment for those and many others. So we say “older” and “elderly.” Where’s the cutoff point for that? I am 84, my husband is 82. I have been diagnosed with mild cognitive impairment with no need to continue seeing a neurologist (so says my current neurologist). We are just plain old, obviously. So I wonder about the terms “older” and “elderly.”

          • Hi Virginia!

            Please be assured that Dr. Kernisan works very hard to make sure her articles have accurate and up to date information. I know that she reviews all the material regularly to make sure it’s current!

            “Old”, “elderly” and even “senior” have fallen out of favour recently in our effort to make language inclusive and accurate. We use the term “older adult” most of the time now. In Geriatrics, I see clients in their 40s and 50s, but usually they’re over 65. The issue can be when ageism makes health providers attribute a symtom to “just being old” rather than something that’s not a normal part of aging and needs more attention.

            I made a video about ageism that you might want to check out: https://youtu.be/l46zUEjr3po

  8. I use cranberry pills for my mother who suffers from lots of things including UTI’s. When she takes these, that problem is one less.

  9. As a chronic UTI sufferer, I was desperate for a solution. I’ve been using the Lady Soma cranberry pills for not too long, but can already feel the difference. They DO NOT aggravate the stomach, as some people have said about cranberries. I do feel a slight difference in regards to stomach, though, but I can’t say if it’s these supplements or something else. But please don’t let that deter you – the Lady Soma Cranberry pills are an absolute godsend. I recommend them full-heartedly. I will be taking these on a daily basis for a very very very long time.

      • i am 83 women with inconnise since 64 yrs been thru all this stuff i want a cafter to wear so i can get some good sleep with out having to get up ever two to three hrs to pee i wear pads but do not sit wet ones i spend more for pad than my electric bill will this be a negative for a cafter in my uretha thank you for all your information i learn more here than the doctors told me thanks again

        • I haven’t yet had time to write an article on the general evaluation and management of incontinence. I would recommend seeing a urogynecologist for persistent incontinence issues, as they do a more thorough evaluation than PCPs do. They should be able to help you manage these issues. Good luck!

        • If you are up frequently in the night to urinate, this can be a sign of sleep apnea. Please tell your family doctor.

          • It’s true that many people with sleep disorders such as sleep apnea experience nocturia (getting up to urinate at night). That said, nocturia is fairly common in general, among older adults, and can be caused by many things other than sleep apnea.

            I completely agree that it’s worth mentioning to one’s health provider, to get assistance and to get evaluation for other concerning symptoms.

    • Hello I went with my mum for check up as she is diabetes. My mum urine Was check by stick and nitrites were found in the urine sample as she has dementia I said i didnt notice any symptoms but she Was prescribe antibiotic 4 times daily. My worry is shoulld she have to take it if she has no symptoms…. and what if she get vaginal infection after this it will be for me imposible to detect.. ANY advice

      • As I explain in the article, the expert recommendation is generally to not treat for bacteria in the urine, unless an older person is also having actual symptoms indicative of a clinical urinary tract infection. Treatment of asymptomatic bacteriuria has been studied in women with diabetes, and the bacteria tend to come back after treatment. Treatment has not been proven to improve longer term outcomes. You may want to ask your mother’s health provider how do they know it’s not asymptomatic bacteriuria, and can they discuss why they think antibiotic treatment is indicated. Good luck!

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