Rhinosporidiosis isolated to the distal clavicle: a rare presentation clinicoradiologically mimicking a bone tumor

Abstract

Rhinosporidiosis is a chronic granulomatous disease caused by Rhinosporidium seeberi, which commonly affects young men and predominantly involves the mucous membranes of the nose, nasopharynx and eyes. Involvement of extranasal sites including bone has been reported, but rarely. We present a case of a 32-year-old farmer, who presented with a non-tender, fixed swelling over his right shoulder. Radiography and CT imaging showed an expansile, lytic, destructive lesion involving the lateral end of the right clavicle with soft tissue extension. The clinicoradiological impression was that of a primary bone tumor. Biopsy and wide excision of the lesion revealed features of rhinosporidiosis. There were no mucocutaneous lesions. Involvement of bone without associated mucocutaneous lesions is exceedingly rare in rhinosporidiosis. Involvement of the clavicle, as seen in the present case, has not been reported in the English language-peer reviewed literature, to the best of our knowledge.

Rhinosporidiosis of distal radius: A case report with review of literature

“…[2,5,7] Only seven cases have been reported till date in English literature mentioning rhinosporidiosis involving bone. [8] …”

“…[5,6] In experimental animal, it is not possible to introduce the disease by inoculation and it is also not possible to culture the organism in vitro or in vivo. [4,8] There is no evidence of transmission of the disease from man to man or animal to man till now. [2,4,8] Usually the lesion presents as a discrete, friable, painless slow-growing polypoidal pedunculated or sessile masses, which are richly vascular and bleeds on touch.…”

“…[4,8] There is no evidence of transmission of the disease from man to man or animal to man till now. [2,4,8] Usually the lesion presents as a discrete, friable, painless slow-growing polypoidal pedunculated or sessile masses, which are richly vascular and bleeds on touch. [1] Nasal mucosa (70%) and conjunctiva is the most common site of infection, but other rare sites are larynx, maxillary antrum, skin of limbs, lachrymal sac, urethra, vagina, parotid duct, bone, and rectum.…”

“…[4,8,14] In cases of bone involvement three clinical settings can occur: (a) bone involvement with presence of mucocutaneous lesion as nasal polyp, (b) as a part of disseminated rhinosporidiosis, and (c) only primary bony lesion without any other organ involvement, [8] as in our case.…”

“…[8] Present case also shows exclusive bone involvement without any evidence of mucocuteneous involvement [ Table 1]. …”