Objective: To report our experience of 11 children with pelvi-ureteric junction obstruction (PUJO) in a duplex kidney and to review previous reports.
Patients and methods: From 1995 to 2005 the second author (G.H.H.S.) performed 145 pyeloplasties in single-system kidneys and in 11 children with PUJO in a duplex kidney. Upper and lower pole obstructions were found in both complete and incomplete duplicated systems. Investigations included renal ultrasonography, renal scintigraphy, micturating cystography, cystoscopy and retrograde pyelography. Ten patients had surgery (eight dismembered pyeloplasties, one upper-pole heminephrectomy, one pyelo-ureterostomy).
Results: Three children had obstruction of the upper moiety and eight had obstruction of the lower moiety. Upper and lower pole obstructions were found in both complete and incomplete duplicated systems.
Conclusion: Upper-pole obstruction in a duplex kidney is rare; the present series suggests that it is more common than previously reported.