A patient with allergic fungal sinusitis (AFS) undergoes FESS. Intraoperative findings include thick, inspissated, greenish-brown 'allergic mucin' filling the sinuses. The characteristic histological finding in this mucin is:
- A Charcot-Leyden crystals and eosinophilic debris with non-invasive fungal hyphae ✓
- B Fungal hyphae invading the sinonasal mucosa
- C Pseudohyphae consistent with candida species
- D Granulomas with central caseation
Correct answer: A. Charcot-Leyden crystals and eosinophilic debris with non-invasive fungal hyphae
Explanation
Allergic fungal sinusitis (AFS) is characterised by the presence of 'allergic mucin' — eosinophilic inspissated secretions containing Charcot-Leyden crystals (eosinophil breakdown products) and non-invasive fungal hyphae (typically dematiaceous fungi such as Bipolaris and Curvularia). The key diagnostic distinction from invasive fungal sinusitis is the absence of mucosal invasion by fungi. It occurs predominantly in atopic, immunocompetent patients with an IgE-mediated hypersensitivity mechanism.
Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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