A urinary tract infection is among the more common maladies that drive patients to primary care practices, yet despite screening and treatment guidelines, some experts still worry that overtreatment contributes to antibiotic resistance.
While these infections are quite common, with an epidemiological study published in the November 2000 Annals of Epidemiology finding that 11% of women reported at least one within the prior 12 months, emerging research into the urinary tract microbiome has revealed that most people harbor high levels of bacteria in their urine as determined through sophisticated genetic probe testing; the clinical implications of this are still unclear. Among women ages 60 years and younger, 3% to 5% will have asymptomatic bacteriuria based on available lab testing, and the likelihood is far higher in older women and men living in long-term care facilities, according to data cited in a 2015 Cochrane review looking at antibiotic use with asymptomatic bacteriuria.
That Cochrane review, which found no benefits and some harms from prescribing antibiotics in asymptomatic individuals, joins other analyses and guidelines highlighting how routine screening can create new dilemmas for physicians. In March, updated guidelines from the Infectious Diseases Society of America (IDSA) on the management of asymptomatic bacteriuria reiterated that routine screening and treatment, barring a few exceptions (such as for pregnant women or individuals prior to a urologic procedure), are not recommended.
Similar recommendations were made in the prior 2005 guidelines, but in some physician practices more frequent screening persists, said Kalpana Gupta, MD, a guideline coauthor and professor of medicine at Boston University School of Medicine. For instance, a urine test is sometimes added to a preoperative workup for a nonurological procedure such as a heart procedure or a hip replacement. The IDSA's guidelines recommend against this practice, said Dr. Gupta, who noted that a positive culture might even delay surgery.
Once that test is run, “then there is this pressure to treat a positive test—that's very strong and engrained in us,” she said. “One of the reasons this guideline got rewritten now is that there is greater awareness of the harms of antibiotics related to [Clostridioides difficile] infections, which are also increasing in community patients.”
In addition, unnecessary antibiotics pose other potential harms, such as side effects and allergic reactions, Dr. Gupta said. “We want to avoid antibiotic use whenever we can if there is not going to be some benefit,” she said.
Thomas Finucane, MD, MACP, takes an even more stringent view, saying that antibiotics could be avoided more frequently even in patients who report symptoms and have significant bacteriuria—if the physician takes the time to convey the potential antibiotic risks. Dr. Finucane published a special article in 2017 in the Journal of the American Geriatrics Society maintaining that a urinary tract infection is an “ambiguous” diagnosis with no precise definition and that several studies have shown that symptoms in uncomplicated cases can recede on their own.
In these cases, patients should be given the option to try a “wait and see” approach, with a prescription in hand to fill if the pain becomes unbearable, said Dr. Finucane, emeritus professor in the division of geriatric medicine and gerontology at Johns Hopkins University School of Medicine in Baltimore. Patients should be advised to always call the office if a fever, pain unrelated to urination, or another worrisome symptom develops, he said.
“You can talk to [the patients] and say, ‘Look, this is going to pass by itself almost certainly. You should call me if you get a fever. Call me if you get sick. Drink a lot of fluids, and let's just see if you can ride it out,’” Dr. Finucane said. “Because the effects of antibiotics are so tremendous and the microbiome is important and it will be completely disrupted by the antibiotics.”
When to screen
In the latest guidelines for asymptomatic bacteriuria, IDSA authors recommend against looking for and treating it in numerous populations, including individuals with diabetes and older patients with functional impairment or who live in long-term care facilities. (According to the data cited in the 2015 Cochrane review, as many as 50% of elderly women in long-term care facilities and as many as 40% of elderly men have asymptomatic bacteriuria.) The American Geriatrics Society, in its ABIM Foundation's Choosing Wisely guidance, cautions against prescribing antibiotics in any older individual without symptoms, outside of a few exceptions, such as those undergoing urinary tract-related procedures.
Some screening in older patients has persisted. One study, which was published in 2012 and looked at adults ages 65 to 84 years who were diagnosed with a urinary tract infection in the ED, found that only 23.9% had reported any urinary tract symptoms.
In years past, a physician might order a urine screen if a patient showed signs of worsening delirium or dementia absent other symptoms, said John Brusch, MD, FACP, a geriatrician and infectious disease specialist at Cambridge Health Alliance in Cambridge, Mass. But physicians have moved away from that approach over the past decade, as studies have shown that the relationship between significant bacteriuria and cognitive changes is more coincidental than causal, he said.
Dr. Brusch said he'll only order a urine test these days if the patient has developed symptoms, such as a fever or discomfort near the kidneys. But sometimes he'll need to educate family members accustomed to prior practice that delirium and dementia can naturally wax and wane and are not related to antibiotic prescribing.
“They are upset because they really expect that every time that Mom gets a little bit more demented, that the doctor gets the urine culture and starts treatment,” Dr. Brusch said. “They always will say, ‘Well, three days after Mom got amoxicillin, she just woke right up.’”
Dr. Finucane points to the IDSA guidelines, which state, “In older patients with functional and/or cognitive impairment with bacteriuria and delirium (acute mental status change, confusion) and without local genitourinary symptoms or other systemic signs of infection (e.g., fever or hemodynamic instability), we recommend assessment for other causes and careful observation rather than antimicrobial treatment (strong recommendation, very low-quality evidence).”
Because delirium sometimes can be the first harbinger of a more serious illness, patients should be closely monitored for other symptoms, Dr. Finucane said. If a patient with or without delirium shows any sign of a severe systemic infection, such as a fever, fast heart rate, or low blood pressure, an antibiotic should be started immediately before urine results come back, Dr. Finucane said. If that test proves to be negative, then the physician can stop the antibiotic targeting the urinary infection, he said.
Treatment decision making
Until the past decade or so, Iris Tong, MD, FACP, said that a woman who called in reporting UTI symptoms would be asked to come in for an office visit regardless of her age.
But now following the emergence of additional data, including a 2002 JAMA study looking at symptoms associated with a UTI, Dr. Tong's practice will often prescribe by phone if the woman is premenopausal, is otherwise healthy, and reports at least one common symptom, such as painful or frequent urination, an urgent need to urinate, traces of blood in the urine, or suprapubic pain.
According to the analysis, published in 2002 in JAMA, a woman who reports at least one of those symptoms has a roughly 50% chance of having a urinary tract infection. If two of those symptoms are paired together—specifically painful urination and frequent urination without vaginal discharge—that likelihood increases to more than 90%.
Dr. Tong said that her practice is typically “really stingy” about prescribing antibiotics, particularly for respiratory illnesses, the vast majority of which are viral in nature. “For UTI, I think that's my one caveat,” said Dr. Tong, an associate professor in the department of medicine at Warren Alpert Medical School of Brown University in Providence, R.I. “The symptoms are so specific, and urinary tract infections are bacterial.”
If a woman is postmenopausal, Dr. Tong typically gets a urine culture first. In such cases, the urinary symptoms could have a cause other than infection, such as irritation from vaginal atrophy. If the woman is otherwise healthy, Dr. Tong might ask her to wait the few days for the results to ensure that the appropriate antibiotic is prescribed. If the postmenopausal woman has other vulnerabilities, such as immune suppression, or is very elderly, Dr. Tong is more likely to start the antibiotic right away as a precaution and then stop it if the urine culture is negative.
But in his commentary in the Journal of the American Geriatrics Society, Dr. Finucane raises the question of whether antibiotic treatment is vital in cases where individuals develop uncomplicated cystitis, regardless of their age. He cited a meta-analysis of five studies that found no benefit of prescribing an antibiotic over a placebo beyond shorter duration of symptoms.
In his older patients with an uncomplicated case of cystitis, with symptoms and a positive culture, Dr. Finucane said that he would describe the risks of antibiotics and ask if they were amenable to holding off on filling the prescription to see if the discomfort faded on its own.
“Antibiotics have lots of adverse effects,” Dr. Finucane said. “But the one that I hate the most is the C. diff diarrhea, which can take a person who is doing well and make them miserable for a long time and kill a few of them.”
Dr. Brusch doesn't support a wait-and-see approach for a confirmed UTI, saying that it risks other complications, such as missing an undiagnosed kidney infection or the emergence of a more systemic infection. If the patient had previously developed C. diff, he said, he would also prescribe metronidazole as a prophylactic measure.
Complex or recurrent cases
Some individuals are more vulnerable to urinary tract infections, such as women who are sexually active, said Megan Schimpf, MD, an associate professor and urogynecologist at the University of Michigan in Ann Arbor. Postmenopausal women are also at higher risk, possibly because estrogen loss alters the bacterial mix in some way, she said.
In cases in which the patient reports seeming UTI-related symptoms but the culture is negative, other possibilities will need to be investigated, such as a sexually transmitted disease, Dr. Gupta said. For postmenopausal women, the loss of estrogen can lead to dryness, irritation, and other changes in the vaginal and urinary tract that can simulate UTI-related symptoms, Dr. Schimpf said. These changes, which are part of a condition now referred to as the genitourinary syndrome of menopause, are sometimes better treated with estrogen.
Other less common possibilities include a condition called painful bladder syndrome (previously known as interstitial cystitis), which can occur in either men or women, Dr. Schimpf said. If blood is in the urine, and particularly if the patient smokes, bladder cancer should be ruled out, she said.
If a patient has recurrent infections, several steps can be recommended, such as prescribing vaginal estrogen for postmenopausal women, Dr. Tong said. Sexually active women can be advised to decrease their use of spermicide and to go to the bathroom after intercourse, she said. Patients also can be reminded about sanitary habits, such as wiping from front to back.
Advising women to boost their water consumption significantly also might make a difference, said Dr. Tong, citing a 2018 study in JAMA Internal Medicine in which premenopausal women who previously reported low fluid intake, and increased their water consumption by an average of 1.5 liters daily, found that they averaged 1.7 cystitis episodes over the 12 months studied versus 3.2 episodes in the low-fluid control group. Dr. Schimpf noted that this recommendation should consider any coexisting overactive bladder symptoms that may worsen substantially with increased fluid intake.
If recurring episodes become too troubling, another option is to prescribe a medication to sterilize the urine or even a low-dose antibiotic regimen. Long-term antibiotics are not an obvious first choice, Dr. Schimpf said. Along with concerns about resistance, an antibiotic can weaken the birth control pill's effectiveness, can have side effects such as C. diff infection, and can lead to yeast infections, she said. Supplements such as cranberry, D-mannose, and probiotics are also low-risk options that have shown promising results in some studies. While not uniformly successful, they have few side effects, she said.
“I don't want to discount how miserable you can be with a bladder infection—it's real,” Dr. Schimpf said. But she tries to avoid prophylactic antibiotics, preferring vaginal estrogen and other approaches first. “Antibiotics are not completely benign,” she said.