A new understanding of UTIs

Urinary tract infection (UTI) is an overused diagnosis that can lead to the myriad harms of antibiotic overtreatment, says Thomas E. Finucane, MD, FACP.

For Thomas E. Finucane, MD, FACP, the concept of urinary tract infections (UTIs) is so mythical, ambiguous, and harmful that he uses quotation marks around the term.

At Johns Hopkins Bayview Medical Center in Baltimore, he even encourages housestaff and colleagues to make air quotes when they say it out loud. “A lot of people have a very resilient idea that if somebody has a ‘UTI,’ they must get antibiotics, and I want to try to undermine the whole construct,” said Dr. Finucane, emeritus professor of medicine in the division of geriatric medicine and gerontology.

Photo courtesy of Dr Finucane
Photo courtesy of Dr. Finucane.

In a special article published online in May by the Journal of the American Geriatrics Society, he describes UTI as an “ambiguous, expansive, overused diagnosis” that can lead to the myriad harms of antibiotic overtreatment. Dr. Finucane has also explored the relationship between UTIs and the microbiome (2017) and bacteriuria and delirium (2014) in articles published by the American Journal of Medicine.

He recently spoke with ACP Hospitalist about medicine's evolving understanding of UTIs, specifically in nonpregnant patients without catheters and with anatomically and functionally normal urinary tracts.

Q: What got you thinking about UTIs in this way?

A: For years, it's been obvious that antibiotic overtreatment of bacteriuria is a very serious problem in geriatrics, and the elderly are particularly subject to overtreatment and particularly at risk to be harmed by the overtreatment. In one study, of all the cultures sent to check for a UTI, change in the smell or appearance of the urine was the reason in about 10%, and there's no evidence, of course, that improving the appearance or the smell of urine by antibiotic treatment benefits the patient in any way. But people see a dirty look in urine or a smell in urine and they say, “Oh, I think there's a UTI. Let's give antibiotics.”

For a young woman with painful urination, it's standard of care to give antibiotics. But the true data show that the pain improves, and it improves a little bit faster than [with] placebo. The bacteria go away a little bit faster if you take the antibiotic, but nothing bad happens to you if you don't take it except that it hurts for a few more days. It's essentially a benign, self-limited condition except for the pain that it causes. And about half the time, there is no bacteriuria.

Q: But what about serious sequelae of UTIs, such as pyelonephritis?

A: There are several randomized controlled trials of young, healthy women who have painful urination, and they're randomized to antibiotic treatment or placebo. There's another couple where they're randomized to antibiotic treatment or ibuprofen. There is a low rate of pyelonephritis in the women who received placebo or ibuprofen, but it's the same rate in the women who receive antibiotics. “UTI” is associated with pyelonephritis; antibiotic treatment does not reduce the risk of pyelonephritis in any of those trials that have been done, or if you sum all of the evidence.

For patients who have asymptomatic bacteriuria, which is often defined as a UTI, there are randomized controlled trials in ambulatory elderly men and women, institutionalized elderly men and women, diabetic women, young women . . . where treating asymptomatic bacteriuria with antibiotics leads to no benefit and to some harm. There's an important trial of women who've had recurrent “UTIs” in the past, meaning acute uncomplicated cystitis (bacteriuria and painful urination), where they come in and they have asymptomatic bacteriuria, and they're randomized either to antibiotic treatment or no treatment at all. . . . It turns out, if you use antibiotics to get rid of the asymptomatic bacteriuria, they get more symptomatic infections in the next year than if you just leave it alone. And that is, by the way, highly understandable, in light of the microbiome.

Q: It seems like in the past few years, we've gotten a greater understanding of the microbiome. How long have we known, for example, that the old thinking that urine is sterile is false?

A: Scientists have demonstrated it several years ago using genetic techniques, where instead of using what we've been using for 135 years and seeing if something will grow on an agar plate, they examine what the genetic material is in the urine. [These] new diagnostic techniques have shown that everybody has bacteriuria all the time, and basically always, there are several different bacterial species living in the bladder and probably in the kidneys of completely asymptomatic people. Newer culture techniques have confirmed these findings. And a virome has been demonstrated, as well.

Q: Did you anticipate this discovery?

A: I don't think I did. To me, the microbiome is the most powerful, important, and astonishing thing that's come to medicine since I got an MD in 1978. It completely revolutionized the way you have to think about people and the world.

Q: What kind of feedback do you get from physicians regarding your way of thinking about UTIs?

A: People are usually vaguely amused and resolved to be more vigilant about it. But a lot of docs know that the rates of treatment of asymptomatic bacteriuria, where it can only be harmful, are pretty high. Many symptoms, including dysuria and delirium, but so many more, are attributed to “UTI” when bacteriuria is found. This way of thinking ignores the fact that bacteriuria is always present if you use modern diagnostic techniques. So if you say, for example, that delirium is caused by bacteriuria, you're saying it's caused by a bacterial species that happens to grow on agar. And that it is safe to ignore all the other species that are in the bladder but are more difficult to identify.

There was one study [of] millions and millions of ED admissions where the patients were discharged with a diagnosis of UTI. If you were over the age of 85, urinary symptoms were mentioned in only 17% of the people. So a guy comes in, he fell down, and he's got bacteriuria, they call him a UTI. He becomes delirious and he's got bacteriuria, they call him a UTI. He comes in and he's just generally not feeling well and his urine just doesn't look normal, they call him a UTI. Asymptomatic bacteriuria is frequently treated, even though the data have been unequivocal for over a decade.

Q: Are urine cultures still routinely ordered for all admitted patients?

A: Until recently, if you were admitted with a heart attack, part of the standard order set was to get a urine culture, and you would get treatment for asymptomatic bacteriuria just because you had a heart attack. There are plenty of stories like that, and there's a very amusing study [where] people were admitted to the hospital and did not have a Foley catheter, but a urine [sample] was sent to the lab for culture.

Normally speaking, you get a report back . . . but in this study, instead of sending back to the ordering physician a lab result, what showed up in the medical record was a statement, something like: “Most bacteriuria in noncatheterized hospital patients is innocent and does not need treatment. It's not a UTI. If you need to know what this result was, call the lab.” And a minority of physicians even called the lab to check up on the test that they had sent. It cut the antibiotic treatment by a substantial amount,and in follow-up after three days, none of those patients was sick in any way that was related to the urinary tract. So you send it by reflex, when it's positive, you say it's a UTI, then you give treatment—and even the most minor hassle factor is enough to divert you from that algorithm.

Q: Can you describe when treating UTIs with antibiotics would be indicated?

A: The biggest category is if a patient is medically unstable with signs of infection, especially signs of sepsis, you have to give antibiotics and you need to do it right away. And that's completely without regard to any findings in the urine. Then, No. 2, if you have bacteremia and it's also in the urine, then you've got to treat the blood infection, and it's reasonable to call that a UTI and assume that it arose in the bladder, although we don't know that to be the case. That has a bunch of names: bacteremic bacteriuria, urosepsis, and there are other names for it.

Let me give you two more: There's pretty good evidence that if you have asymptomatic bacteriuria and you're pregnant, probably you should take antibiotics. That is the recommendation from the Infectious Diseases Society of America (IDSA). And then, in people who are about to have invasive procedures on the urinary tract, if they have asymptomatic bacteriuria, the [IDSA] recommendation is to give them antibiotics just before the procedure.

Q: What's the connection between UTIs and delirium?

A: A common scenario is usually a woman in long-term care with cognitive impairment who is judged to be suddenly more confused than usual and has bacteriuria, and she comes to the ED and they say the UTI is causing the delirium, and she gets hammered with antibiotics. There is a series of position papers: One says delirium is not a feature of UTIs; a second says you shouldn't send urine specimens because of delirium, even if you suspect bacteriuria; and the third says don't treat a delirious patient for UTIs just because they're delirious.

If you go into a long-term care facility and take a bunch of women especially, who are completely well and doing fine and no different than they were a week ago, and you get a urine sample, maybe 40% or 50% of them have asymptomatic bacteriuria. . . . We're guaranteed that a good number of the cases are coincidental, and yet, in many places, everybody gets UTI workup and treatment if they're delirious, and that's harmful at several levels.

Q: Looking ahead, what do you anticipate happening in this area?

A: Glacial change. Everybody has seen a delirious patient have bacteriuria, get antibiotics, and get better. The antibiotic treatment of self-limited conditions is uniformly gratifying. It's very deeply embedded in the psyche of the docs, and the patients, and the patients' families. So all of those factors add up against any radical change.

Q: How would you like to see hospitalists change their approach to UTIs?

A: For me, on the inpatient side, assuming that the patient is not looking septic, doesn't look severely ill, and is in with delirium [or another condition] and incidentally discovered bacteriuria, the right thing is always to culture her up, follow her vigilantly, and hold the antibiotics if she's stable and getting better. If her blood cultures are positive, you've got to treat that, but most of the time, if the urine is positive and blood cultures are negative, she gets better in a few days and you've saved her from a lot of risk and some expense. I [recommend] a full informed-consent discussion instead of saying, “She's got a UTI. We're giving her antibiotics.”