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Updated: Jun 22, 2026
Oral Biofilm Analysis of Palatal Expanders by Fluorescence In-Situ Hybridization and Confocal Laser Scanning Microscopy
Published on: October 20, 2011
Identification of adenoid biofilms with middle ear pathogens in otitis-prone children utilizing SEM and FISH
Michael Hoa1, Senja Tomovic, Laura Nistico
1Department of Otolaryngology-Head and Neck Surgery, Wayne State University School of Medicine, Detroit, MI, USA.
Objectives:
Biofilms have been implicated in the development of several chronic infections. We sought to demonstrate middle ear pathogens in adenoid biofilms using scanning electron microscopy (SEM) and fluorescent in situ hybridization (FISH) with confocal laser scanning microscopy (CLSM).
Methods:
Comparative micro-anatomic investigation of adenoid mucosa using SEM and FISH with confocal scanning laser microscopic (CLSM) imaging from patients with recurrent acute otitis media (RAOM).
Results:
All otitis-prone children demonstrated biofilm surface area presence greater than 85% by SEM. FISH accompanied by CLSM imaging also demonstrated patchy biofilms All biofilms contained middle ear pathogens and were frequent in polymicrobial distributions: 4 of 6, 4 of 6 and 3 of 6 samples contained Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis, respectively.
Conclusions:
Dense adenoid biofilms may act as a reservoir for reinfection of the tubotympanum. Aspiration of planktonic middle ear pathogens existing in resistant adenoid biofilms during a viral upper respiratory tract infection may be an important event in the development of RAOM.
Insights
Dense biofilms in adenoids harbor middle ear pathogens, contributing to recurrent acute otitis media (RAOM). These biofilms may serve as a reservoir for reinfection, particularly during viral infections.
Area of Science:
- Microbiology
- Otolaryngology
- Infectious Diseases
Background:
- Biofilms are linked to chronic infections.
- Adenoid biofilms may harbor pathogens causing middle ear infections.
Purpose of the Study:
- To detect middle ear pathogens within adenoid biofilms.
- Utilize scanning electron microscopy (SEM) and fluorescent in situ hybridization (FISH) with confocal laser scanning microscopy (CLSM).
Main Methods:
- Comparative micro-anatomic investigation of adenoid mucosa.
- SEM and FISH with CLSM imaging were performed on patients with recurrent acute otitis media (RAOM).
Main Results:
- Over 85% of otitis-prone children showed significant biofilm presence via SEM.
- FISH-CLSM confirmed patchy biofilms containing common middle ear pathogens like Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis.
Conclusions:
- Adenoid biofilms can act as a reservoir for tubotympanic reinfection.
- Pathogen aspiration from biofilms during viral infections may drive RAOM development.
