Invasive Fungal Rhinosinusitis: The First Histopathological Study in Vietnam

Area of Science:

• Medical Mycology
• Pathology
• Infectious Diseases

Background:

• Invasive fungal rhinosinusitis (IFRS) is a rare, highly fatal condition.
• Key pathogens include Mucorales and Aspergillus, necessitating distinct therapeutic approaches and carrying different prognoses.

Purpose of the Study:

• To elucidate the histopathological characteristics of IFRS.
• To assess the reliability of histopathology in differentiating fungal pathogens in IFRS.

Main Methods:

• Retrospective analysis of 57 IFRS cases.
• Independent histopathological examination of H&E, PAS, and GMS-stained slides by two pathologists.
• Fungal identification using PCR, guided by histopathology.

Main Results:

• IFRS predominantly affects males (1.4:1 ratio) with a mean age of 58.9 years; diabetes was present in 100% of cases.
• Mucorales (61.4%) and Aspergillus (33.3%) were the primary fungal agents identified, with no co-infections.
• Histopathology and PCR showed high concordance (Cohen's kappa = 84.2%). Mucormycosis cases presented with more extensive necrosis and vascular invasion compared to non-Mucormycosis cases.

Conclusions:

• IFRS impacts older males, often with diabetes.
• Histopathology is a reliable method for distinguishing between Mucorales and Aspergillus in IFRS.
• Extensive necrosis and vascular invasion are key indicators for differentiating fungal agents and warrant careful investigation.