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Published on: June 14, 2020
The Relationship between Colonization by Moraxella catarrhalis and Tonsillar Hypertrophy
Mirela C M Prates1, Edwin Tamashiro1, José L Proenca-Modena2,3,4
1Department of Ophthalmology, Otorhinolaryngology, Head and Neck Surgery, Ribeirao Preto Medical School, University of São Paulo, Ribeirao Preto, SP 14049-900, Brazil.
Insights
Potentially pathogenic bacteria like Haemophilus influenzae and Streptococcus pneumoniae are common in children with adenotonsillar hypertrophy. Moraxella catarrhalis detection in multiple sites correlates with severe hypertrophy, suggesting a role in its development.
Area of Science:
- Microbiology
- Pediatric Otolaryngology
- Infectious Diseases
Background:
- Chronic adenotonsillar hypertrophy is a common condition in children.
- The role of specific bacterial pathogens in the development and severity of adenotonsillar hypertrophy requires further investigation.
Purpose of the Study:
- To investigate the prevalence of potentially pathogenic bacteria in secretions and tonsillar tissues of children with chronic adenotonsillar hypertrophy compared to controls.
- To explore the association between bacterial detection and the severity of adenotonsillar hypertrophy.
Main Methods:
- Prospective case-control study involving children aged 2-12 years.
- Real-time PCR was used to detect Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, Pseudomonas aeruginosa, and Moraxella catarrhalis.
- Samples included palatine tonsils, adenoids, and nasopharyngeal washes from children with and without adenotonsillar hypertrophy.
Main Results:
- High frequencies (>50%) of Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, and Pseudomonas aeruginosa were detected in both groups.
- Adenoids and palatine tonsils of patients with severe hypertrophy showed higher rates of bacterial coinfection.
- Simultaneous detection of Moraxella catarrhalis in adenoids, palatine tonsils, and nasopharyngeal washes correlated with more severe tonsillar hypertrophy.
Conclusions:
- Common bacteria such as Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae, and Moraxella catarrhalis are frequently found in the upper respiratory tract of children.
- Moraxella catarrhalis may be associated with the development of more severe adenotonsillar hypertrophy, potentially due to inflammatory conditions favoring its colonization.
Abstract:
We sought to investigate the prevalence of potentially pathogenic bacteria in secretions and tonsillar tissues of children with chronic adenotonsillitis hypertrophy compared to controls. Prospective case-control study comparing patients between 2 and 12 years old who underwent adenotonsillectomy due to chronic adenotonsillar hypertrophy to children without disease. We compared detection of Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, Pseudomonas aeruginosa, and Moraxella catarrhalis by real-time PCR in palatine tonsils, adenoids, and nasopharyngeal washes obtained from 37 children with and 14 without adenotonsillar hypertrophy. We found high frequency (>50%) of Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, and Pseudomonas aeruginosa in both groups of patients. Although different sampling sites can be infected with more than one bacterium and some bacteria can be detected in different tissues in the same patient, adenoids, palatine tonsils, and nasopharyngeal washes were not uniformly infected by the same bacteria. Adenoids and palatine tonsils of patients with severe adenotonsillar hypertrophy had higher rates of bacterial coinfection. There was good correlation of detection of Moraxella catarrhalis in different sampling sites in patients with more severe tonsillar hypertrophy, suggesting that Moraxella catarrhalis may be associated with the development of more severe hypertrophy, that inflammatory conditions favor colonization by this agent. Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae, and Moraxella catarrhalis are frequently detected in palatine tonsils, adenoids, and nasopharyngeal washes in children. Simultaneous detection of Moraxella catarrhalis in adenoids, palatine tonsils, and nasopharyngeal washes was correlated with more severe tonsillar hypertrophy.
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