A Case of Osseous Metaplasia in the Uriner System Causing Severe Urinary Obstruction

Osseous metaplasia within urinary tract is a very rare entity. Nowadays the use of traditional imaging methods seems to be not sufficient to make differentional diagnosis of urinary tract stone to osseous metaplasia. The pathophysiology of heterotopic bone tissue formation was defined nearly hundred years ago. The renal Osseous metaplasia has been considered to be associated with mucosal injury, ischemia, trauma or carcinogenesis. An osseous metaplasia was detected on the ureter without any stone encrustation, so that the entity was thought to be the primary lesion. In our case we detected cristalloids surrounding the osseous metaplasia.