A 55-year-old diabetic male presents with 2-week history of unilateral nasal blockage, orbital pain, and eschar formation in the nasal cavity. MRI shows T2 hypointense signal in the nasal cavity with perineural spread along V2. The most likely organism responsible is:
- A Aspergillus fumigatus
- B Mucor/Rhizopus species ✓
- C Candida albicans
- D Pseudomonas aeruginosa
Explanation
The clinical picture of a diabetic patient with unilateral nasal eschar, orbital involvement, perineural spread, and T2 hypointense signal on MRI is classic for acute invasive (fulminant) fungal sinusitis caused by Mucorales (Mucor/Rhizopus species). These are angioinvasive fungi that cause thrombosis of blood vessels leading to tissue necrosis and eschar. T2 hypointensity reflects hypercellular fungal hyphae. Aspergillus causes chronic invasive sinusitis in immunocompromised patients (non-diabetic) and is septate; Mucor is non-septate (pauciseptate) with right-angle branching.
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.