Disease Information for Rhinosporidiosis

Rhinosporidiosis is a chronic granulomatous disorder caused by Rhinosporidium seeberi; It frequently involves the nasopharynx and occasionally affects the skin; The organism has never been isolated in vitro, and its taxonomic position is unclear; The disease is endemic in India and Sri Lanka but has also been reported from the United States, South America, and Iran ; It is more common in adult men and is possibly transmitted to humans by direct contact with spores through dust, through infected clothing or fingers, and through swimming in stagnant waters ; Rhinosporidiosis frequently involves the nasopharynx (70 %) presenting as a painless, friable, polypoidal growth, which may hang anterior to the nares or posteriorly into the pharynx; The lesions are pink or purple-red and studded with minute white dots, which are sporangia containing the spores ; Nasal obstruction and bleeding are the most common symptoms; The conjunctiva and lacrimal sac are involved in 15 percent of cases; Occasionally, rhinosporidiosis affects the lips, palate, uvula, maxillary antrum, epiglottis, larynx, trachea, bronchus, ear, scalp, vulva, vagina, penis, rectum, and the skin;

Histopathological examination of the skin biopsy specimen from the representative cutaneous lesions shows hyperplastic epithelium with numerous globular cysts of varying shape, representing sporangia in different stages of development; He is restarted on dapsone (100 mg po per day); Discussion: Rhinosporidiosis is usually limited to the surface epithelium of nasal mucosa, but, rarely, wide dissemination with visceral involvement can occur; The nasal lesions start as an often-pruritic papule that grows into an erythematous polypoidal mass that may cause obstruction of the nose and nasopharynx; Small cysts and pseudocysts develop and may discharge a combination of pus, mucus, and organisms, creating tiny white dots on the lesion"s surface and giving lesions a characteristic strawberry-like appearance ; Cutaneous lesions in rhinosporidiosis are not very common and usually start as friable papillomas that become pedunculated ; Cutaneous rhinosporidiosis may also present as warty papules and nodules with whitish spots, crusting, and bleeding on the surface; Three types of skin lesions can occur: (1) satellite lesions, in which skin adjacent to the nasal rhinosporidiosis is involved secondarily; (2) generalized cutaneous type with or without nasal involvement, occurring through hematogenous dissemination of the organism; (3) primary cutaneous type associated with direct inoculation of organisms on to the skin; Careful inspection of the surface of warty lesions and the presence of typical nasopharyngeal lesions usually help in the diagnosis of cutaneous rhinosporidiosis; The various differential diagnoses include warts, verrucous tuberculosis and granuloma pyogenicum ; The diagnosis can easily be clinched by performing a Giemsa-stained imprint smear ; Fine-needle aspiration cytology from the lesion may be an additional diagnostic tool ; Histopathology reveals enormous number of mycotic elements in the subepithelial connective tissue; These elements consist of sharply defined globular thick-walled cysts (sporangia), up to 0_5 mm in diameter, which contain numerous rounded endospores, 6-7 µ in diameter; Immature and collapsed sporangia are also present; Occasionally microabscesses may form; This disease must be differentiated from coccidiodomycosis whose different clinical presentation and smaller sporangia size (less than 60 µ in diameter) allow for an easy distinction ; Surgical removal and electrodesiccation are the treatments of choice ; Dapsone may arrest the maturation of sporangia and accelerate degenerative changes in them; The effete organisms are then removed by an accelerated granulomatous response;

---------------------------[Indian Dermatology Journal abstract-Google search 2007]----------------------------

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