A 25-year-old patient from the Gangetic plain of India presents with a slowly progressive, destructive ulceration of the nose and midface involving the palate and pharynx, described as 'facial granuloma'. Biopsy shows foamy macrophages packed with organisms. Which organism causes this condition?
- A Histoplasma capsulatum
- B Rhinosporidium seeberi ✓
- C Leishmania donovani
- D Mucor species
Correct answer: B. Rhinosporidium seeberi
Explanation
Rhinosporidium seeberi causes rhinosporidiosis, endemic in India and Sri Lanka, presenting as friable polypoidal lesions of the nose and nasopharynx. Histopathology shows large sporangia filled with endospores. Though long classified as a fungus, molecular studies place it as a protistan parasite (Mesomycetozoea). Histoplasma shows yeast in macrophages, Leishmania shows amastigotes, and Mucor shows aseptate hyphae.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.