Infants younger than four weeks old who have a history of fever but who remain fever-free during an observation period in the emergency department for serious bacterial infection (SBI) are good candidates for early discharge, new research suggests.

About one-third of neonates who are evaluated in the ED for serious infection with reported fever are afebrile on initial presentation and these infants are thought to have the same risk of infections as those febrile at presentation, Dr. Sriram Ramgopal and colleagues from UPMC Children’s Hospital of Pittsburgh point out in a paper online in Pediatrics.

But their retrospective chart review of infants evaluated for SBI at their center does not support this notion. Of 931 infants (mean age, 18 days; 54.5 percent boys), 60.2 percent had fever on presentation, 29.9 percent were afebrile with no subsequent fever, and 10.0 percent were afebrile at presentation but developed a fever during their hospital stay.

Infants with history of fever but afebrile on presentation and throughout their hospital stay had a significantly lower likelihood of SBI compared with those with a fever at presentation (odds ratio, 0.42; 95 percent confidence interval 0.23 to 0.79), although differences in invasive bacterial infection were not statistically significant.

In infants who were fever-free at first but developed a fever during their hospital stay, the median time to fever was 5.6 hours. This group had significantly higher odds of SBI (OR, 1.93, 95 percent CI 1.07 to 3.50) than did those with fever at presentation.

“Findings from this study suggest that a subset of initially afebrile infants tested for SBI who remain afebrile may be candidates for earlier discharge after a shorter observation period,” the researchers conclude in their article.

In email to Reuters Health, Dr. Ramgopal said, “There is already a body of expert opinion and evidence to suggest that it might be appropriate to discharge well appearing infants worked up for SBI after 24 hours. However, this is still not commonly practiced. This study might provide data to support the decision to discharge infants earlier in that particular population of infants who are only historically febrile and who remain afebrile after 20-24 hours of observation.”

However, the researchers emphasize that the decision to discharge after a period of observation must take into account multiple factors, including “the clinical appearance of the child, the total time the infant remained afebrile, any preliminary positive culture results, the provision of empirical antibiotics before discharge, and the ability of the treating physician to reach the caregiver in the event of a positive result.”