Otitis media with effusion is not a sterile inflammatory process: scanning electron microscope evidence

Area of Science:

• Otolaryngology
• Microbiology
• Pathology

Background:

• Chronic otitis media with effusion (OME) is a common pediatric condition.
• The underlying pathophysiology of OME, specifically whether it is sterile or biofilm-mediated, remains debated.

Purpose of the Study:

• To investigate the role of biofilms in chronic otitis media with effusion (COME).
• To differentiate between sterile and biofilm-related causes of COME using direct visualization and culture methods.

Main Methods:

• A case-control study involving 60 children with COME (cases) and normal middle ear mucosa (controls).
• Scanning electron microscopy (SEM) was used to visualize middle ear mucosa for biofilm formation.
• Middle ear effusion (MEE) cultures were performed, and adenoid size was correlated with biofilm presence.

Main Results:

• Biofilm formation was significantly higher in COME patients (84%) compared to controls (p < 0.001).
• Cultures were positive in only 24% of COME patients, with most biofilm-positive cases showing negative cultures.
• Streptococcus pneumoniae was the most frequent otopathogen; adenoid size negatively correlated with biofilm grade.

Conclusions:

• Direct visualization confirms the presence of middle ear biofilms in COME, indicating a biofilm-related etiology.
• Biofilms should be considered in pediatric OME, particularly in cases not requiring adenoid surgery.