A 22-year-old man from coastal Karnataka presents with a painless, pinkish, pedunculated mass protruding from his right nostril, bleeding on touch. Biopsy shows large thick-walled sporangia filled with numerous endospores. He recalls frequently bathing in ponds. The most likely diagnosis is:

• A Rhinoscleroma due to Klebsiella pneumoniae subsp. rhinoscleromatis
• B Nasal polyp with allergic fungal sinusitis
• C Rhinophyma
• D Rhinosporidiosis ✓

Explanation

Rhinosporidium seeberi produces vascular, friable polypoidal masses of the nose and nasopharynx, classically in people bathing in stagnant water in South India and Sri Lanka. Histology is diagnostic: large spherical sporangia (up to several hundred micrometres) packed with endospores. Klebsiella rhinoscleroma shows Mikulicz cells with bacilli on Warthin-Starry stain, not sporangia, which excludes option A.

Reference: Ananthanarayan and Paniker's Textbook of Microbiology, 12th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.