BACKGROUND

Current guidelines and recent studies on pediatric pneumonia pertain to children older than 3 months of age. Little information exists regarding the diagnostic evaluation, management, and outcomes of infants less than 90 days with pneumonia.

METHODS

We compared infants <90 days of age diagnosed with pneumonia across 38 US children's hospitals from 2016 to 2021 to children 90 days to 5 years of age. We evaluated whether differences exist in patient characteristics, diagnostic testing, antibiotic treatment, and outcomes between young infants and older children. Additionally, we assessed seasonal variability and trends over time in pneumonia diagnoses by age group.

RESULTS

Among 109 796 children diagnosed with pneumonia, 3128 (2.8%) were <90 days of age. Compared with older children, infants <90 days had more laboratory testing performed (88.6% vs 48.8%, P < .001; median number of laboratory tests 4 [interquartile range: 2-5] vs 0 [interquartile range: 0-3] respectively), with wide variation in testing across hospitals. Chest radiograph utilization did not differ by age group. Infants <90 days were more likely to be hospitalized and require respiratory support than older children. Seasonal variation was observed for pneumonia encounters in both age groups.

CONCLUSIONS

Infants <90 days with pneumonia were more likely to undergo laboratory testing, be hospitalized, and require respiratory support than children 90 days to 5 years of age. This may reflect inherent differences in the pathophysiology of pneumonia by age, the manner in which pneumonia is diagnosed, or possible overuse of testing in infants.