Question
Rhinosporidiosis
Answer
Rhinosporidiosis is a chronic granulomatous infection, most classically affecting the nasal mucosa, caused by Rhinosporidium seeberi — an organism now generally regarded as an aquatic protistan parasite (Mesomycetozoea) rather than a true fungus, though traditionally studied alongside fungal infections.
Epidemiology: associated with exposure to stagnant water (bathing in ponds/rivers) or contaminated soil/dust, particularly common in South Asia including India; transmission is presumed to occur via direct inoculation of spores into traumatized nasal/ocular mucosa.
Clinical features: a slow-growing, friable, vascular, polypoid mass in the nasal cavity, causing nasal obstruction and recurrent epistaxis; the nose is the most common site, though conjunctival/ocular involvement can also occur.
Laboratory diagnosis: primarily histopathological — biopsy shows large, thick-walled sporangia containing numerous endospores; the organism has never been successfully cultured in vitro, an important diagnostic limitation.
Treatment: surgical excision with cauterization of the base is the mainstay, since no reliably effective antimicrobial/antifungal therapy exists; recurrence after incomplete excision is common.