title: [Consensus on diagnostic strategies in connatal dilatations of the urinary tract].
abstract: Anomalies of the urinary tract are detected by ultrasound screening in one out of one hundred newborns. In most cases, dilatations of the upper urinary tract result from ureteropelvic junction obstruction or a primary megaureter. Especially in these cases, it is essential to differentiate between an obstruction defined as a stenosis potentially leading to progressive parenchymal damage from a dilatation without any consequences for renal function. The main criteria for assessment of urinary transport are ultrasound examinations to observe the dilatation of the collecting system, washout of the tracer during diuresis renography and lastly split renal function. Standards for investigation procedures are required to ensure comparability of treatment concepts and especially for prospective randomized studies planned for the future. A consensus concerning basic diagnostic strategies has been elaborated by a task force group consisting of members of the "Arbeitsgemeinschaft für Pädiatrische Nephrologie" in cooperation with the "Arbeitskreis Kinderurologie" in the German Society of Urology and the "Kinderurologische Arbeitsgemeinschaft" in the German Society of Pediatric Surgery with advice from leading pediatric radiologists and specialists in pediatric nuclear medicine. The main contents of this consensus are reported.