Association Between Nasopharyngeal Colonization and Clinical Outcome in Children With Acute Otitis Media.

Background: Young children with acute otitis media (AOM) frequently exhibit nasopharyngeal colonization with either Streptococcus pneumoniae, Haemophilus influenzae or both pathogens. We aimed to determine if antibiotics could be spared or shortened in those without nasopharyngeal colonization with either pathogen.

Methods: In 2 separate randomized clinical trials in children aged 6-23 months with stringently-diagnosed AOM, we performed bacterial cultures on nasopharyngeal specimens collected at the time of diagnosis. In the first trial, we compared the efficacy of amoxicillin/clavulanate (amox/clav) administered for 10 days vs. that of placebo, and in the second trial, we compared the efficacy of amox/clav administered for 10 days vs. 5 days. In each trial, we classified children as being colonized with both S. pneumoniae and H. influenzae, S. pneumoniae alone, H. influenzae alone, or neither pathogen, and as experiencing either clinical success or clinical failure at the end-of-therapy visit, based on previously reported a priori criteria.

Results: We evaluated 796 children. Among children randomized to amox/clav, those colonized with either S. pneumoniae or H. influenzae or both were approximately twice as likely to experience clinical failure as children not colonized with either pathogen (odds ratio: 1.8; confidence intervals: 1.2-2.9). In contrast, among children randomized to placebo, clinical failure at the end-of-therapy visit was not associated with nasopharyngeal culture results at the time of diagnosis.

Conclusions: Children colonized with either S. pneumoniae or H. influenzae or both have a greater chance of treatment failure than children colonized with neither pathogen.