Ureteropelvic junction disease.

The term "ureteropelvic junction disease" defines any form of hydronephrosis consequent to a congenital anomaly of the ureteropelvic junction. It is one of the most common congenital urological anomalies. Over one third of patients have an associated uropathy. The etiology is not clear: an error in the embryonic development with consequent abnormal anatomy and function of ureteropelvic junction is suggested. The clinical presentation is the determining factor in its management. The widespread use of pre- and neonatal sonography has originated a new population of asymptomatic patients with no clearcut indication for surgery. For these patients, a complete follow-up is required to prevent renal function impairment. Surgery is mandatory for symptomatic patients. When indicated, Anderson-Hynes pyeloplasty is the gold standard surgical technique.