Stewardship in the pediatrician’s office: Appropriate antibiotic use for UTIs
UTIs account for 1.1 million pediatric office visits annually and are a significant clinical syndrome in childhood. UTI is typically caused by a bacterial pathogen. The infection involves the lower urinary tract (ie, urethritis, cystitis) or the upper urinary tract (ie, pyelonephritis). Prompt treatment of pyelonephritis is important to prevent renal scarring and associated sequela such as hypertension and end-stage renal disease.
Early recognition of UTI at the initial office visit relies on identification of risk factors, clinical signs and symptoms in conjunction with urine testing. A rapid diagnostic test such as urine dipstick is convenient, inexpensive and may be the only test available in the office. Urinalysis, using either automated or enhanced microscopy, is available in the laboratory setting.
The presence of pyuria/leukocyte esterase alone or along with nitrite/bacteriuria in urine dipstick or urinalysis increases the probability of UTI. Although growth of a uropathogen on urine culture is the gold standard, the result might not return for 1 to 2 days. Hence, the decision to start empiric antibiotics is primarily based on clinical characteristics and results of either dipstick or urinalysis. In this column, we address the usefulness of point-of-care testing and choice of appropriate empiric antibiotics.
1. Confronting the conundrum of appropriate antibiotic prescription:
The clinical presentation of UTI in infants and young children includes fevers and nonspecific signs and symptoms, such as irritability and poor feeding. Parental reports of foul-smelling urine or GI symptoms, such as vomiting or diarrhea, are not helpful. The probability of UTI increases in the following scenarios:
- infants aged younger than 12 months;
- maximum reported temperature exceeding 39°C (102.2°F);
- uncircumcised boys;
- children who are not Black; and
- no other source of fever, such acute otitis media, viral syndrome or gastroenteritis, etc.
The University of Pittsburgh has a UTI calculator on its website to help with clinical decision-making. In older children and adolescents, presentation includes fevers along with signs and symptoms of UTI, such as dysuria, urinary urgency, urinary frequency, abdominal pain, etc.
Given nonspecific presentation in infants and young children, rapid urine testing significantly helps in the diagnosis of UTI. In older children and adolescents, it further affirms clinical suspicion. A urine culture should be sent in all suspected cases with clinical findings consistent with UTI and in situations in which the rapid test is indicative of UTI (presence of leukocyte esterase, nitrite in dipstick and detection of pyuria, leukocyte esterase alone or along with nitrite and bacteriuria in urinalysis).
In infants and young children who are not toilet trained, the urine sample preferably should be obtained through catheterization because the reliability of the culture result is diminished with a bag specimen. Another option is to obtain urine through the most convenient method of bag collection. In these cases, the decision to send urine culture should be based on the presence of inflammation markers like pyuria and leukocyte esterase, as well as the presence of bacteria markers, such as nitrite and bacteriuria, on the dipstick or urinalysis. In toilet-trained children, a clean-catch specimen will suffice for urine collection.
Growth of a uropathogen such as Escherichia coli greater than 50,000 colony-forming units/mL, along with evidence of inflammation on urinalysis — eg, pyuria with greater than 5 WBC/hpf in automated microscopy, or greater than 10 WBC/hpf in enhanced microscopy — is suggestive of a true UTI. The most common bacteria causing UTI in children are gram-negative Enterobacteriacea. Primarily it is E. coli, and then Klebsiella spp., Proteus spp., Pseudomonas spp. and Enterobacter spp. Gram-positive organisms such as enterococci are less common. Staphylococcus saprophyticus accounts for 15% of pediatric UTIs and is typically reported in adolescents.
Choice of antibiotic
Empiric antibiotic treatment should be considered in a child with high probability of UTI at the initial office visit. A compatible clinical presentation coupled with the presence of inflammatory markers (pyuria, leukocyte esterase) alone or along with markers suggestive of the presence of bacteria (nitrite, bacteriuria) back up treatment.
The empiric antibiotic choice should be based on the local outpatient pediatric UTI antibiogram. For example, the antibiogram for New York City is available through the New York City Department of Health and Mental Hygiene’s website. If a local community antibiogram is not available, you can certainly review pediatric antibiograms from local hospitals. They include children in the community diagnosed with UTI in the ED.
Children aged older than 1 year without any major genitourinary tract malformation can be treated with oral antibiotics. Organisms are highly resistant to commonly used antibiotics such as amoxicillin and sulfamethoxazole/trimethoprim in most U.S. communities. Therefore, either a third-generation oral cephalosporin (cefdinir, cefixime or cefpodoxime), or a first-generation oral cephalosporin (cephalexin or cefadroxil) should be used based on the local antibiogram. One should also take into account factors associated with the risk for antibiotic resistance:
- a recent antibiotic course over the past 30 days;
- recent hospitalization;
- presence of urinary catheter; or
- presence of anatomic genitourinary abnormalities.
Once the urine culture returns with the identification of the organism as well as the susceptibility pattern, the antibiotic should be tailored accordingly. Another aspect of antibiotic stewardship is the duration of treatment. Febrile UTI or pyelonephritis in infants and young children are treated for 7 to 14 days. In older children with cystitis, a duration of 3 to 7 days is adequate.
2. Practice guidelines for outpatient settings:
Clinical practice guidelines, including those for the management of febrile UTI in infants aged 2 months to 24 months, are available through the American Academy of Pediatrics. A reaffirmation of these AAP guidelines was published in 2016.
In a study of 910 patients, the implementation of a urine culture follow-up protocol increased the rate of the discontinuation of empiric antibiotics in cases with a negative urine culture from 4% to 84% in less than 3 years. In addition, a quality improvement intervention, including education and process improvement activities based on evidence-based clinical guidelines, resulted in a sustained use of narrow-spectrum antibiotics in a pediatric outpatient health care facility.
3. Operationalizing an antimicrobial stewardship program (ASP) in your office through quality improvement and EHRs:
Opportunities to improve UTI ASP efforts can start with a gap analysis to make sure that physicians are following best practice guidelines for diagnosis, treatment and follow up after urine culture results are available. An initial step could be creating and educating clinicians on practice guidelines based on AAP recommendations and the local antibiogram and resistance patterns. These guidelines — along with other key elements, such as comorbidities — can then be used to create a documentation template. Incorporating treatment guidelines with preferred narrow-spectrum antibiotic choices based on local resistance patterns and appropriate duration of treatment in the documentation template and/or creating an ordering pathway in the form of an order set can further nudge clinicians to make appropriate antibiotic choices for the management of UTI.
Finally, a systematic plan for patients who were started on antibiotics based on abnormal urinalysis but were noted to have negative urine cultures is another ASP opportunity to reduce unwarranted antibiotic use. Adding the prescribed antibiotic on the urine culture lab order (EHRs may vary in their report displays) may facilitate the process of recognizing and discontinuing antibiotics when cultures are negative (depending upon the reporting system, comments added during an order are visible in the results).