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Changes in nasopharyngeal flora during otitis media of childhood
H Faden1, J Stanievich, L Brodsky
1Division of Pediatric Infectious Diseases, State University of New York School of Medicine, Children's Hospital of Buffalo 14222.
Insights
During otitis media, common respiratory pathogens like nontypable Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis significantly increase in children's nasopharyngeal flora. Their absence in nasopharyngeal cultures suggests they are not in the middle ear.
Area of Science:
- Microbiology
- Pediatrics
- Infectious Diseases
Background:
- Otitis media is a common childhood infection.
- The nasopharyngeal flora plays a role in the pathogenesis of otitis media.
- Nontypable Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis are common causes of otitis media.
Purpose of the Study:
- To compare the nasopharyngeal flora of healthy children with that of children experiencing otitis media.
- To investigate the changes in carriage and quantity of specific bacteria during otitis media episodes.
- To determine the predictive value of nasopharyngeal cultures for identifying middle ear pathogens.
Main Methods:
- Prospective study comparing 40 healthy children with 70 children experiencing otitis media.
- Nasopharyngeal cultures were collected and analyzed for bacterial flora.
- Quantitative analysis of bacterial load was performed during healthy and infected periods.
Main Results:
- Carriage and quantity of nontypable H. influenzae, S. pneumoniae, and M. catarrhalis significantly increased during otitis media episodes.
- Resident nasopharyngeal flora, such as viridans streptococci, decreased during otitis media.
- Absence of a pathogen in nasopharyngeal culture had a high negative predictive value (>0.96) for middle ear infection.
Conclusions:
- Respiratory pathogens become more dominant in the nasopharynx during otitis media.
- Nasopharyngeal cultures can be a reliable indicator for the absence of middle ear pathogens.
- Understanding nasopharyngeal flora dynamics is crucial for managing otitis media.
Abstract:
The nasopharyngeal flora of healthy children were compared with flora in children with otitis media caused by nontypable Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis. Forty healthy children were followed prospectively and compared with 70 children with 43 episodes of nontypable H. influenzae, 21 episodes of S. pneumoniae and 28 episodes of M. catarrhalis otitis media. Carriage of nontypable H. influenzae (95% vs. 65%, P less than 0.001), S. pneumoniae (91% vs. 52%, P less than 0.005) and M. catarrhalis (86% vs. 52%, P less than 0.001) increased significantly during episodes of otitis media compared with healthy periods. The quantity of nontypable H. influenzae, S. pneumoniae and M. catarrhalis in nasopharyngeal secretions also increased during active infection compared with healthy periods: 3.0 vs. 2.0, P less than 0.005; 3.2 vs. 2.1, P less than 0.001; and 3.3 vs. 2.5, P less than 0.01, respectively. At the same time, nonpathogens of the resident flora, in particular viridans streptococci, declined in carriage: 65% vs. 22%, P less than 0.001. These data suggest that respiratory pathogens become relatively more important in the microenvironment of the nasopharynx during episodes of otitis media. Furthermore the absence of a middle ear pathogen in a nasopharyngeal culture strongly suggests that the pathogen is not present in the middle ear space (negative predictive value greater than 0.96).