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UTI Treatment
UTI Treatment: Beyond the Guidelines

Released: February 18, 2026

Nicolás Cortés-Penfield
Nicolás Cortés-Penfield, MD, FACP, FIDSA
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Key Takeaways
  • A systematic approach to diagnosing complicated urinary tract infections (cUTI) and identifying sources of recurrence is key to appropriate treatment and treatment escalation.
  • For people with spinal cord injury and neurogenic bladder, urine studies should only be ordered when clinical signs and symptoms indicate infection, as this population is prone to cUTI misdiagnosis.
  • Ertapenem can be used in place of meropenem or imipenem for empiric treatment of cUTI, but I would hesitate to recommend fosfomycin as a first-line option for cUTI, owing to insufficient clinical trial data and real-world experience.

How do you approach recurrent complicated urinary tract infection (cUTI), and when do you consider antibiotic prophylaxis?
It's important to take a systematic approach to patients seeking care for recurrent urinary tract infection (UTI). First, we need to establish that the patient is actually having recurrent episodes of infection and not, for example, that UTI is being repeatedly misdiagnosed on the basis of abnormal urine studies or chronic symptoms due to another pathology, such as interstitial cystitis or chlamydial urethritis. A key point is that both pyuria and bacteriuria are ubiquitous in patients with indwelling or intermittent urinary catheterization. These are expected findings, often do not reflect pathology, and are unlikely to be persistently resolved with antibiotics. 

Once we are confident the patient is indeed experiencing recurrent UTI, the next step is to identify and address potential sources of recurrence. Patients who have not yet had abdominopelvic imaging to identify potentially infected nephrolithiasis or other sources should undergo this imaging. Patients with indwelling catheters, ureteral stents, nephrostomies, or other urologic hardware should be evaluated for device removal if feasible. Men with recurrent UTI should undergo evaluation for chronic prostatitis, which entails referral to urology or performance of a Meares-Stamey 2-glass or 4-glass test by another healthcare professional familiar with those procedures.

Postmenopausal women should be considered for topical vaginal estradiol therapy, which results in little systemic exposure and has a substantial body of evidence for reducing recurrent UTI, with modern data suggesting it is safe in patients with a history of estrogen-mediated cancers.

Other simple interventions like increasing fluid intake, teaching the patient double voiding techniques to improve bladder emptying, urinating after intercourse, and ceasing douching should also be suggested. Cranberry products, specifically, those containing a daily dose of at least 36 mg of proanthocyanidin, are widely available without a prescription, low-risk, and supported by multiple clinical trials as another simple intervention to reduce recurrent UTI.

In patients who continue to experience recurrent UTI despite the initial interventions described above, a good next step would be to offer methenamine, an old drug that is converted into the antiseptic formaldehyde in urine. A couple of clinical trials suggest it is about as effective as prophylactic antibiotics for preventing recurrent UTI. Starting with methenamine mitigates the risk of C. difficile colitis with antibiotic prophylaxis and helps preserve antibiotic susceptibilities if or when the patient presents with a systemic life-threatening infection. 

Finally, when a patient continues to have recurrent UTI despite attempting the more benign interventions above, we can consider antibiotic prophylaxis. Comparative data on the optimal approach to antibiotic prophylaxis and its long-term efficacy are scarce, but reasonable options include continuous prophylaxis (eg, trimethoprim-sulfa daily or 3 times weekly), postcoital prophylaxis, or a "pill in pocket" approach in which a patient is prescribed 1 or more courses of antibiotic therapy and advised to self-initiate at the onset of symptoms. However, healthcare professionals considering continuous prophylaxis should be cautious when selecting nitrofurantoin, as prolonged use of this drug is associated with pulmonary toxicity. Patients in whom antibiotic prophylaxis for recurrent UTI is being considered often benefit from evaluation by an infectious disease specialist.

How does the approach to cUTI diagnosis differ in patients with spinal cord injury and neurogenic bladder?
Diagnosing cUTI in patients with spinal cord injuries leading to neurogenic bladder poses a unique challenge for 2 reasons.

First, these patients are often insensate at the relevant levels and so may not experience typical urinary symptoms such as dysuria, urgency, suprapubic or flank pain, etc.

Second, the neurogenic bladder arising from said injury typical necessitates suprapubic or intermittent straight catheterization, which is both a genuine risk factor for cUTI and a source of persistent pyuria and bacteriuria, which in turn frequently leads to misdiagnosis of cUTI.

A key point here is that routine urinalysis and urine cultures should be avoided. This patient population is prone to cUTI misdiagnosis, leading to inappropriate therapy and iatrogenic harm. Instead, it is critical to only order urine studies in these patients when clinical signs and symptoms have already raised suspicion for infection.

Unfortunately, there are no high-quality studies validating the diagnostic utility of UTI symptoms in patients with spinal cord injury. Fever, rigors, and acute delirium may be the first clear-cut signs of UTI in these patients but unfortunately are late signs of progressive systemic infection. Earlier signs may include spasticity, autonomic dysfunction, diaphoresis, or atypical descriptions of abdominopelvic discomfort (eg, "bladder squeezing").

Treatment of acute episodes of UTI in patients with spinal cord injury and neurogenic bladder is similar to cUTI in the general population, and I would take the same general approach to recurrent UTI as described above. Again, when considering antibiotic prophylaxis for recurrent UTI in these patients, avoiding iatrogenic harm is paramount. Misdiagnosing and overtreating these patients can quickly lead to persistent colonization with extensively drug-resistant uropathogens with few or no oral treatment options. This in turn could lead to a worse prognosis for future episodes of true severe systemic infection, and major financial and quality of life burdens for even mild episodes of infection that become more difficult to treat outside the hospital setting due to limited treatment options.

Can ertapenem be used in place of meropenem or imipenem for empiric treatment of cUTI?
Absolutely! The most common uropathogen in nearly all forms of UTI is E. coli. Pseudomonas aeruginosa can cause UTI but is not one of its primary pathogens. Unless a patient has a specific risk factor for pseudomonal UTI, such as prior recent episodes of UTI with P. aeruginosa, empiric antipseudomonal therapy is generally not indicated.

Can fosfomycin be used to treat cUTI?
This is an interesting question. Fosfomycin was not included in the list of preferred or alternative empiric antibiotic options for cUTI in the recent IDSA guideline. Although some observational evidence suggests that fosfomycin may be adequate for step-down therapy to complete cUTI treatment, that body of evidence is much smaller than those for other oral antibiotic classes, with limited real-world experience for cUTI.

Also, although oral fosfomycin concentrates well in urine, the levels achieved in renal tissue and blood are substantially lower. Fosfomycin certainly has a role in the treatment of uncomplicated UTI, and an ID specialist might use it in specific cases of cUTI where oral alternative were unsuitable, but I would hesitate to recommend it as a first-line option for cUTI, particularly when pyelonephritis or bacteremia are present.

Your Thoughts
How do you approach diagnosis and treatment of cUTI? When do you think antibiotic prophylaxis is appropriate? Leave a comment to join the discussion!

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