A missed diagnosis of retrocaval ureter; case report and review of the literature.

The retrocaval ureter is an uncommon congenital anomaly due to an abnormal development of the inferior vena cava. Our case describes an 8 year-old boy who was referred to our center as a case of ureteropelvic junction obstruction with persistent hydronephrosis after pyeloplasty. Retrograde pyelogram showed features of retrocaval ureter which was managed surgically with constructive repair of the ureter. The low clinical incidence may be due to a number of asymptomatic cases that are not diagnosed in the patient's lifetime.