Fungal colonization of the paranasal sinuses

Area of Science:

• Otorhinolaryngology
• Mycology
• Immunology

Background:

• Fungal sinusitis presents in four types: acute invasive, chronic invasive, fungus ball, and allergic fungal sinusitis.
• Invasive fungal sinusitis can be fatal, particularly in immunosuppressed patients.
• This study focuses on non-invasive mould colonization in immunocompetent individuals with chronic sinusitis.

Purpose of the Study:

• To investigate the prevalence and nature of fungal presence in the paranasal sinuses of immunocompetent patients with chronic sinusitis.
• To differentiate between fungal colonization and invasive mycosis in this patient group.

Main Methods:

• Analysis of 132 paranasal sinus tissue samples from 117 immunocompetent patients undergoing endoscopic surgery (1994-1998).
• Mycological and histological examinations were performed on samples showing granulomatous material during endoscopy.
• Fungal species were identified, and invasive growth was assessed.

Main Results:

• Fungi were detected in 24.9% of patients and 25.7% of specimens.
• Aspergillus fumigatus was the most common isolate (17 times), followed by other Aspergillus species (6 times).
• Histological examination revealed no invasive mycelial growth, indicating commensal colonization rather than mycosis.

Conclusions:

• The findings suggest that moulds commonly colonize the paranasal sinuses in immunocompetent patients with chronic hyperthrophic sinusitis.
• This colonization is likely facilitated by impaired mucociliary clearance due to increased mucus production.
• While not a mycosis in this population, such colonization could pose an invasion risk for immunosuppressed patients.