WASHINGTON – Beta-lactam monotherapy is likely to be just as effective as a combination of beta-lactam and macrolide therapy for the majority of children hospitalized with pneumonia, a study has shown.
A subanalysis of a large national study found no difference in the length of hospital stay for children with pneumonia, whether they had received ceftriaxone alone or in combination with azithromycin, Dr. Derek J. Williams said at the annual meeting of the Pediatric Academic Societies.
"This is an important finding, because we know that limiting antimicrobial use to the narrowest-spectrum agent for the shortest duration is imperative to slow the epidemic of antimicrobial resistance," said Dr. Williams, a pediatrician in the division of hospital medicine at Vanderbilt University, Nashville, Tenn.
His large retrospective study used data collected in the Etiology of Pneumonia in the Community (EPIC) study. Sponsored by the Centers for Disease Control and Prevention, EPIC now contains information on 1,496 children.
Dr. Mark Shen
Dr. Williams’ study involved 941 children who were admitted to hospitals with presumed community-acquired pneumonia. Most of these (678) were treated with ceftriaxone alone; 263 received combination therapy with ceftriaxone and azithromycin.
There were some important baseline differences between the groups, Dr. Williams noted. Children in the combination group were significantly older than those in the monotherapy* group (median, 64 months vs. 19 months). They were also significantly more likely to have asthma (44% vs. 35%) or other high-risk comorbidities including cardiopulmonary, oncologic, or immunosuppressive conditions; hepatic or renal problems; metabolic or genetic issues; and neurodevelopmental disorders.
The median length of hospital stay was 64 hours in both groups. Neither an unadjusted nor adjusted analysis found any significant relationship between therapy type and length of stay.
A propensity score matching looked at the outcome in 190 children in each exposure group. It too found no significant relationships.
The results are in line with a national pediatric pneumonia treatment guideline, published in 2011 in Clinical Infectious Diseases (53:617-30),Dr. Williams said.
During discussion, however, he noted that the conclusions may be somewhat marred by the nature of the EPIC cohort. "Although more than 80% of EPIC children received antibiotics, a bacterial pathogen was identified in only 15%."
This prompted some comment from pediatric hospitalist Mark W. Shen of the Dell Children’s Medical Center of Central Texas, Austin.
"The EPIC study is probably one of our most robust studies looking at the etiology of community-acquired pneumonia in hospitalized kids," he said. "But it seems now that you could argue that potentially more than 85% of these could have a viral etiology for their disease. So that would make it exceedingly difficult to find any inherent differences in antibiotic treatment. Is there any gold standard for figuring out how we can assess the comparative effectiveness, if most of these cases could be viral?
"This is the big issue that we struggle with," said Dr. Williams. "How do we define bacterial pneumonia? Our methods for detecting viruses are far superior to those we use to detect bacteria. I think this is coming with biomarkers, but we are not there yet. I think we’re underestimating bacterial disease and coinfections, but I also think that retrospective data are just not as good as prospective. Until we are able to really define this, that’s going to be a difficult question to answer."
Dr. Shen was also an author on a poster at the meeting. His study found that the hospitalist changed or stopped antibiotics in 93% of children with pneumonia who were started on one during the emergency department visit. "Sixty percent of the time, we found that there was no difference in their outcomes," he said.
The EPIC study is funded by the Centers for Disease Control and Prevention. Dr. Williams said he had no relevant financial disclosures. Dr. Shen was listed in the program as having no financial disclosures.
*Correction, 6/26/13: An earlier version of this story misstated the type of therapy group in the description of the study.