title: Acquired ureteropelvic junction obstruction in childhood.
abstract: Ureteropelvic junction (UPJ) obstruction is generally considered to be a congenital lesion or occasionally an intermittent phenomena relating to periods of increased urine flow. Acquired ureteropelvic junction obstruction without a recognizable secondary cause is quite unusual. We present a 5.5-year-old boy who, 4 years after repair of a right sided UPJ obstruction, developed a significant left-sided UPJ obstruction in a system which previously had been normal.
mesh_terms: D002675:Child, Preschool; D006801:Humans; D006869:Hydronephrosis / Q000000981:diagnostic imaging; D007223:Infant; D007682:Kidney Pelvis / Q000000981:diagnostic imaging*; D008297:Male; D011859:Radiography; D012008:Recurrence; D014517:Ureteral Obstruction / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery