The risk of serious bacterial infections among young ex-premature infants with fever

Background and ObjectivesTo determine the rate of serious-bacterial-infections (SBI) in young ex-premature infants with fever, and to develop a risk-stratification algorithm for these patients. MethodsA retrospective cohort study including all infants who presented to the pediatric emergency department (ED) of a tertiary-care university-hospital between 2010 and 2020 with fever (>= 38 degrees C), were born prematurely (<37-weeks), had post-conception age of <52-weeks, and had available blood, urine, or CSF cultures. The rates of SBI by age-of-birth and age-at-visit were calculated and compared to a cohort of matched full-term controls. ResultsThe study included a total of 290 ex-premature cases and 290 full-term controls. There were 11 cases (3.8%) with an invasive bacterial infection (IBI) of either bacteremia, meningitis or both and only six controls (2.1%) with IBI (p = 0.32). Over 28-days chronologic-age, there were 10 (3.6%) IBIs among cases and no IBIs among the controls (p = 0.02). There were eight (3%) cases and three (1%) controls with IBI who were well-appearing on physical examination (p = 0.19). All eight well-appearing ex-premature infants were under 60-days adjusted-age, seven of whom (88%) were also under 28-days adjusted-age. There were 28 (10.6%) cases and 34 (12%) controls with urinary tract infection (UTI) (p = 0.5). Among cases under 60-days adjusted-age, urinalysis was not reliable to exclude UTI (50% negative). ConclusionsWell-appearing ex-preterm infants have a significant risk for IBI until the adjusted age of 28-days and for UTI until the adjusted age of 60-days. Further studies are needed to evaluate the approach to fever in this unique population.

Automated summary

This study aimed to determine the rate of serious bacterial infections (SBI) in young ex-premature infants with fever and develop a risk-stratification algorithm. The study found that well-appearing ex-preterm infants had a significant risk for invasive bacterial infection (IBI) until the adjusted age of 28 days and for urinary tract infection (UTI) until the adjusted age of 60 days. Further studies are needed to evaluate the approach to fever in this unique population.