A patient with chronic rhinosinusitis undergoes imaging. The CT shows complete opacification of all sinuses on one side with expansion of the affected sinuses and thinning of the bony walls. Intraoperatively, the sinus contains thick, inspissated, dark green-brown material with a peanut butter consistency. What is the most likely diagnosis?

• A Antrochoanal polyp
• B Allergic fungal rhinosinusitis ✓
• C Inverted papilloma
• D Mucocoele of the maxillary sinus

Explanation

Allergic fungal rhinosinusitis (AFRS) is characterised by the triad of atopy, nasal polyps, and thick inspissated eosinophilic mucin (allergic mucin) containing fungal hyphae (most commonly Bipolaris or Aspergillus). The dark, peanut butter-like material is pathognomonic. CT shows hyperdense heterogeneous material due to calcium, iron, and manganese in the inspissated mucin. Sinus expansion and bony remodelling (not frank destruction) occur due to pressure effects.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.