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Abstract: PO2277

Risk Factors for Urinary Tract Infection Caused by Extended-Spectrum Beta-Lactamase Gram-Negative Bacteria in Infants

Session Information

Category: Pediatric Nephrology

  • 1700 Pediatric Nephrology


  • Ahn, Yo Han, Seoul National University Children's Hospital, Seoul, Korea (the Republic of)
  • Kim, Ji hyun, Seoul National University Bundang Hospital, Seongnam, Korea (the Republic of)
  • Lee, Juyoung, Inha University Hospital, Incheon, Korea (the Republic of)
  • Lim, Seonhee, Seoul National University Children's Hospital, Seoul, Korea (the Republic of)
  • Kang, Hee Gyung, Seoul National University Children's Hospital, Seoul, Korea (the Republic of)

Community-acquired extended-spectrum beta-lactamase (ESBL) producing bacterial infections are an evolving public health problem. Urinary tract infections (UTIs) due to ESBL-producing bacteria are increasing even in infants rarely exposed to antibiotic. We aimed to identify risk factors for UTI caused by ESBL-positive bacteria in infants.


We retrospectively analyzed the medical records of hospitalized infants with the first episode of UTI from 2018 to 2019. Data includes demographic characteristics, birth history, previous use of antibiotics, febrile event, urinalysis results, and urine isolated organisms. Multivariate regression analysis was used to quantify independent risks associated with ESBL-positive UTI.


UTIs were diagnosed in 266 patients at a median age of 3.6 (interquartile range (IQR) 2.3-5.4) months. Sixty-two (30.4%) patients were diagnosed with UTI caused by ESBL-producing bacteria. When we divided patients according to ESBL status, there was no difference in gender, age, birth history, milk type, and use of postpartum care centers. Maternal use of antibiotics during pregnancy and previous antibiotic exposure to patients was higher in the ESBL-positive group than in the ESBL-negative group (32.3% vs. 10.3%, P <0.001, and 22.6% vs. 12.3%, P =0.044, respectively). Klebsiella species was more frequently identified in the ESBL-positive group than in the ESBL-negative group (19.4% vs. 4.9%, P =0.002). In multivariate analysis, maternal use of antibiotic during pregnancy (odds ratio (OR), 3.817; 95% confidence interval (CI) 1.812-8.040, P <0.001), previous antibiotic exposure to patients (OR 2.418; 95% CI 1.071-5.461, P =0.034), and Klebsiella species as a causative organism (OR 6.222; 95% CI 2.396-16.158, P <0.001) were associated with ESBL positivity. In a comparison of clinical courses of patients, the ESBL-positive group showed severe leukocytosis (WBC 16,795 /μL vs. WBC 14,620 /μL, P =0.04), and stayed longer in hospital than the ESBL-negative group (7.0 days vs. 4.5 days, P <0.001).


In this study, the high rate of ESBL positivity was detected in infantile UTI. Antibiotics exposure on both patients and mothers was associated with UTI caused by ESBL producing bacteria. Identification of underlying risk factors could improve treatment and preventive strategies.