title: Bone metaplasia in the urinary tract: a new radiological sign.
abstract: We report 7 cases of bone tissue in the upper urinary tract. Routine excretory urography was suspicious for renal lithiasis. However, pathological evaluation of the kidney tissue revealed bone metaplasia in all 7 cases. Retrospective examination of the first 6 cases showed a typical radiological sign, consisting of a radiopaque eccentric halo surrounding an area of lesser radiological density that, in turn, connected with the urothelium. These findings permitted a correct preoperative diagnosis of bone metaplasia in case 7. Accurate preoperative differentiation of bone metaplasia (false calculi) and true renal lithiasis is important owing to the different treatments required.
mesh_terms: D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000000981:diagnostic imaging*; D007674:Kidney Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D007682:Kidney Pelvis / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D009999:Ossification, Heterotopic / Q000000981:diagnostic imaging* / Q000473:pathology; D011859:Radiography