title: Excretory urographic demonstration of ureteral displacement by sigmoid fecal impaction simulating retroperitoneal tumor.
abstract: Two cases of curvilinear lateral ureteral displacement in children with abdominal masses are reported. The masses proved to be sigmoid fecal impactions. This possibility must be considered before embarking on radiographic or surgical evaluation of possible retroperitoneal neoplasm.
mesh_terms: D002675:Child, Preschool; D012809:Colon, Sigmoid; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D011859:Radiography; D012186:Retroperitoneal Neoplasms / Q000175:diagnosis*; D014515:Ureteral Diseases / Q000000981:diagnostic imaging* / Q000209:etiology; D014555:Urination Disorders / Q000209:etiology