Routine blood cultures may not be necessary for most children hospitalized with community-acquired pneumonia (CAP), researchers conclude based on a large multicenter cross-sectional study.

The study found that the rate of bacteremia is “very low” among children hospitalized with CAP, first author Dr. Mark Neuman, from Boston Children’s Hospital and Harvard Medical School, told Reuters Health by email. And when bacteremia is present, “a majority of pathogens are susceptible to narrow-spectrum antibiotics, such as penicillin,” he said.

These findings suggest that among children without chronic conditions hospitalized with CAP, the routine performance of blood cultures has limited value “because the results would rarely require changes from guideline-recommended, empirical antibiotic therapy,” the study authors write.

As reported in Pediatrics online August 23, the study team evaluated the utility of blood cultures in more than 7,500 children hospitalized with CAP (without comorbid conditions) at six children’s hospitals over a five-year period (2007-2011). A blood culture was obtained in 2,568 children (34 percent) and 65 (2.5 percent) grew a pathogen. Streptococcus pneumoniae made up 78 percent of all detected pathogens.

Among the pathogens detected, 50 (82 percent) were susceptible to penicillin. Only 11 children demonstrated growth of an organism not susceptible to penicillin, representing 0.43 percent of children who had blood cultures and 0.15 percent of all children hospitalized with CAP.

Current guidelines from the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America call for blood cultures in children hospitalized for presumed bacterial CAP that is moderate to severe.

Dr. Neuman told Reuters Health he thinks it is time to revisit the guidelines on routine blood cultures in kids hospitalized with CAP, “particularly among children without medical complexity hospitalized in a non-ICU setting.”

In their article, the researchers say future studies “should seek to identify the clinical characteristics of children in whom obtaining blood cultures would lead to changes in clinical management, especially when identifying those patients at risk for CAP caused by organisms not susceptible to guideline-recommended, narrow-spectrum antibiotics.”