Rhinosporidiosis B48.10

Seeber, 1900

Granulomatous infectious disease of the mucous membranes, particularly the nasopharynx, oropharynx, conjunctiva, rectum and external genitalia, caused by Rhinosporidium seeberi, an aquatic protozoon

Rhinosporidium seeberi. The germ could not be cultivated in cultures or inoculated in experimental animals.

Occurs mainly in tropical and subtropical areas. Sporadically distributed worldwide.

The mode of infection is still unclear, probably a transmission of the spores when bathing in fresh water.

Mostly occurring in men.

Mainly nose (posterior sections, 70%), also conjunctiva (14%), throat, palate, bronchus, larynx, genital organs.

Irregularly shaped, brittle, greyish red, slow-growing, broad-based, polyp-like, slightly bleeding growths with small, yellowish-grey spots on the surface (sporangia). Disseminated forms are possible.

Granulomatous inflammation with neutrophils, histiocytes, plasma cells, microabscesses, giant cells of the Langerhans type. Numerous round cysts surrounded by a lattice shell with numerous nuclei = sporangia (100-400um in diameter) of Rhinosporidium seeberi filled with thawing endospores.

Swab specimen. Microscopic examination.

Polyps; condylomata lata; angioma; fibroma; sarcoma; leprosy; tuberculosis; blastomycosis; rhinoscleroma, granuloma teleangiectaticum, leishmaniasis.

Electrocaustic, surgical removal far in the healthy area. All drug therapies are ineffective so far.

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7. Seeber G (1900) Un nuevo esporozuario parasito del hombre: dos casos encontrados en polipos nasales. Thesis, Universidad Nacional de Buenos Aires