Chronic middle ear effusions. Immunochemical and bacteriological investigations

Area of Science:

• Otolaryngology
• Immunology
• Microbiology

Background:

• Serous otitis media is common in children.
• Understanding the immune environment of middle ear effusions is crucial.

Purpose of the Study:

• To investigate local immune responses in middle ear effusions.
• To determine the relationship between immune factors, effusion type, and bacterial presence in otitis media.

Main Methods:

• Analysis of middle ear effusions and sera from 100 pediatric patients.
• Quantification of IgA, IgG, and lysozyme levels.
• Bacteriological examination (smear and culture) of effusions.

Main Results:

• Elevated IgA, IgG, and lysozyme in effusions compared to sera suggest local production.
• Mucoid effusions had higher immunoglobulin and lysozyme levels than serous effusions.
• Bacteria identified in 77% of effusions; 52% showed positive culture, with higher rates in younger children (<6 years).
• Bacterial recovery inversely correlated with increasing age-related immune factor levels.

Conclusions:

• Otitis media involves a local immune response within the middle ear.
• Immune factors like IgA, IgG, and lysozyme play a role in combating bacterial infection.
• Bacterial load in middle ear effusions decreases with age, potentially due to maturation of the local immune system.