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Published on: December 4, 2020
Previous antimicrobial exposure is associated with drug-resistant urinary tract infections in children
Amanda A Paschke1, Theoklis Zaoutis, Patrick H Conway
1Children's Hospital of Philadelphia, Division of Infectious Diseases, 3615 Civic Center Blvd, ARC 1202, Philadelphia, PA 19104, USA. paschke@email.chop.edu
Insights
Recent antimicrobial exposure increases the risk of antimicrobial-resistant urinary tract infections (UTIs) in children. This risk diminishes over time, highlighting the need for judicious antibiotic use.
Area of Science:
- Pediatric infectious diseases
- Antimicrobial resistance
- Epidemiology of childhood infections
Background:
- Urinary tract infections (UTIs) are common in children.
- Antimicrobial resistance is a growing global health concern.
- Understanding factors contributing to resistance is crucial for effective treatment.
Purpose of the Study:
- To assess the impact of prior antimicrobial exposure on the development of antimicrobial resistance in children experiencing their first UTI.
- To identify specific antimicrobial agents and exposure windows associated with increased resistance.
Main Methods:
- Retrospective cohort study of 533 children aged 6 months to 6 years with a first UTI diagnosis.
- Analysis of antimicrobial exposure within 120 days prior to UTI diagnosis.
- Multivariable logistic regression models to assess associations between exposure and resistance, adjusting for confounders.
Main Results:
- 21% of children had antimicrobial exposure within 120 days before their first UTI.
- Amoxicillin exposure within 30 or 31-60 days was linked to ampicillin resistance (OR 3.6 and 2.8, respectively).
- Amoxicillin exposure within 30 days was associated with amoxicillin-clavulanate resistance (OR 3.9).
Conclusions:
- Recent antimicrobial exposure, particularly amoxicillin, is associated with antimicrobial-resistant UTIs in pediatric outpatients.
- The association between exposure and resistance decreases as the time since exposure increases.
- Clinicians should consider recent antimicrobial history when prescribing empiric antibiotics for UTIs and minimize unnecessary antimicrobial use.
Objective:
The aim of this study was to evaluate the impact of previous antimicrobial exposure on the development of antimicrobial resistance in children with their first urinary tract infection (UTI).
Methods:
We conducted a retrospective cohort study of children aged 6 months to 6 years and received their first diagnosis of UTI in a network of 27 outpatient pediatric practices between July 1, 2001, and May 31, 2006. We examined the relationship between antimicrobial resistance in UTI isolates and exposure to specific antimicrobial agents (amoxicillin, amoxicillin-clavulanate, cefdinir, trimethoprim-sulfamethoxazole, and azithromycin) in the previous 120 days. We developed multivariable logistic regression models for resistance to ampicillin, amoxicillin-clavulanate, trimethoprim-sulfamethoxazole, and first-generation and third-generation cephalosporins, adjusting for potential confounders such as age, number of siblings, recent hospitalizations, and child care exposure.
Results:
Of the 533 children who had a first UTI, 8%, 14%, and 21% were exposed to antimicrobial agents within 30, 60, and 120 days before the UTI, respectively. Amoxicillin exposure within 30 days (odds ratio [OR]: 3.6 [95% confidence interval (CI): 1.6-8.2]) and 31 to 60 days (OR: 2.8 [95% CI: 1.0-7.5]) before UTI both were associated with ampicillin resistance. Exposure to amoxicillin >60 days before the UTI was not associated with ampicillin resistance. Amoxicillin exposure within 30 days of UTI was also associated with amoxicillin-clavulanate resistance (OR: 3.9 [95% CI: 1.8-8.7]). No association between exposure to other antimicrobial agents and resistance to any of the antimicrobial agents was seen.
Conclusions:
Recent antimicrobial exposure is associated with antimicrobial-resistant UTIs among pediatric outpatients, and the magnitude of this association decreases with time since exposure. Judicious antimicrobial prescribers should consider this association when selecting empiric antimicrobial agents for a new UTI and should use strategies to reduce unnecessary antimicrobial use to avoid development of resistant bacteria.
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