Factors Associated With Bacteremia in Young Infants With Urinary Tract Infection

Diana Averbuch, MD; Ran Nir-Paz, MD; Ariel Tenenbaum, MD; Polina Stepensky, MD; Rebecca Brooks, MD; Benjamin Z. Koplewitz, MD; Ari M. Simckes, MD; Dan Engelhard, MD


Pediatr Infect Dis J. 2014;33(6):571-575. 

In This Article

Abstract and Introduction


Background: Urinary tract infection (UTI) is the most frequent severe bacterial infection in infants. Up to 31% of infants with UTI have bacteremia.

Methods: We retrospectively identified all infants aged 0–2 months who were managed in our hospital with UTI during a 1-year period. Those with bacteremia were compared with those without bacteremia, according to the following variables: ethnicity, age, gender, white blood cell and polymorphonuclear counts, C-reactive protein, urinalysis and blood creatinine values as related to age-appropriate norms, imaging and outcome.

Results: We identified 81 infants with 82 episodes of UTI. Most occurred in males (72.8%) and 35 (42.7%) were in infants of non-Jewish origin. In 14/81 (17.3%) of episodes, Escherichia coli was cultured from blood. In multivariate analysis, increased blood creatinine levels (P = 0.004) and non-Jewish origin (P = 0.006) were associated with bacteremia. Time to defervescence was significantly longer in bacteremic versus nonbacteremic children (P = 0.018). Duration of hospitalization was longer in bacteremic infants—10 (7–17) days in bacteremic versus 7 (1–14) days in nonbacteremic children (P < 0.001).

Conclusions: In infants aged 0–2 months with UTI, increased blood creatinine value at admission was associated with bacteremia. This value provides an additional clue on admission, independent of personal judgment, to help identify infants at higher risk for bacteremia, prolonged hospitalization and possible complications.


Urinary tract infection (UTI) is one of the most common causes of serious bacterial infections in infants <90 days of age. UTI occurs in 0.1–1% of term neonates[1–4] and is a cause of fever in 5–13.6% of febrile infants <8 weeks of age.[5–9] One study found that 85% of serious bacterial infections in infants <90 days of age resulted from UTI.[10] In children with UTI, the rate of concurrent bacteremia has been reported as 0–31%.[5,11–16]

Identification at presentation of infants who will subsequently be diagnosed with bacteremia may enable identification of those prone to complications.[15] The purpose of this study was to identify risk factors at presentation associated with bacteremia in febrile infants aged 0–60 days.