Fellow University Texas Southwestern Medical Center The University of Texas Southwestern Medical Center, Department of Pediatrics Dallas, Texas, United States
Background: Depending on age and demographic differences, approximately 5-31% of children <24 months with febrile urinary tract infection (UTI) have concomitant bacteremia. Early diagnosis and prompt antibiotic therapy in children with bacteremic UTI is critical to prevent short- and long-term complications. Serum inflammatory markers have variable predictive values in young children with bacteremic UTI.
Objective: The objective of our study is to identify urinary markers that can predict bacteremia in young children with febrile UTI.
Design/Methods: Retrospective review of medical records of febrile children <24 months of age with UTI, who had blood culture evaluation during their emergency department visit from January 2012 to December 2017. UTI was defined based on American Academy of Pediatrics clinical practice guideline thresholds. Pyuria was defined as ≥5 white blood cells per high-power-field, urine bacteria was considered positive if ≥1+ bacteria on microscopic urinalysis (UA), leukocyte esterase (LE) was positive if small or more on dipstick, and urine specific gravity (USG) was arbitrarily categorized into <1.015 and ≥1.015. We performed univariate and multivariable logistic regression analyses to evaluate UA predictors of bacteremia in children with febrile UTI at α=0.05 significance level, using SAS 9.4
Results: Of 1853 febrile children with UTI, 813 had blood culture evaluation. Of these 409 (50%) were males, 469 (58%) were <90 days of age, 497 (61%) were Hispanic, and 804 (99%) had in-and-out transurethral catheterization. In this population, 720 (89%) had positive LE, 704 (86%) had pyuria, 534 (66%) had urine bacteria, 308 (38%) had positive nitrite,713 (88%) patients had Escherichia coli (E. coli) UTI, and 82 (10%) had positive blood culture.
Univariate predictors of bacteremia based on prevalence odds ratio (pOR) estimates (Table 1) include, age<90 days, USG<1.015, LE, urine bacteria, and E. coli UTI. After adjusting for age, urine bacteria (pOR 1.8, 95%CI 1.1-3.2), USG<1.015 (pOR 3.3, 95%CI 1.4-9.6), LE (pOR 2.9, 95%CI 1.1-12.0), and E.coli UTI (pOR 6.0, 95%CI 1.8-36.9) remained as significant predictors of bacteremia in febrile infants with UTI. Pyuria and nitrite were not significant predictors of bacteremia. Conclusion(s): Urinalysis may be useful in predicting bacteremic UTI in febrile children < 24 months of age. Significant predictors after adjusting for patient’s age include urine specific gravity <1.015, positive leukocyte esterase, and urine bacteria. Further studies are needed to validate our findings.
Authors/Institutions: Matthias M. Manuel, The University of Texas Southwestern Medical Center Department of Pediatrics, Dallas, Texas, United States; Vatsal Patel, The University of Texas Southwestern Medical Center, Dallas, Texas, United States; Shahid Nadeem, The University of Texas Southwestern Medical Center Department of Pediatrics, Dallas, Texas, United States
