First10 EM - By Brian Lee and Denis Ren - February 13, 2023
The paper: Mahajan P, VanBuren JM, Tzimenatos L, et al; Pediatric Emergency Care Applied Research Network (PECARN). Serious Bacterial Infections in Young Febrile Infants With Positive Urinalysis Results. Pediatrics. 2022 Oct 1;150(4):e2021055633. doi: 10.1542/peds.2021-055633. PMID: 36097858
Outcomes: The primary outcome was the prevalence of bacteremia or bacterial meningitis in infants with a positive urinalysis (growth of a pathogen in the urine or CSF culture). There were no secondary outcomes.
Our thoughts: Not surprisingly, infants </= 60 days with a positive urinalysis demonstrated higher rates of bacteremia, supporting the current practice of obtaining a blood culture in this population. With respect to meningitis, the presence or absence of a positive urinalysis did not alter the risk of bacterial meningitis in the first month of life. In older infants (>28 days), the authors report no cases of bacterial meningitis in patients with a positive urinalysis. While certainly reassuring, the low prevalence of bacterial meningitis in this age group is blessing and a curse. A recent meta-analysis reported that infants with a positive urinalysis had similar rates of meningitis to those with negative urinalysis. Ultimately, these finding further supports the most recent American Academy of Pediatrics guideline suggesting that not all infants >28 days old require CSF analysis and that the decision to perform lumbar puncture in this age group should be made using shared decision making with the family.