Surgical intervention for pediatric ureteropelvic junction obstruction When should this measure be considered?

Background: Ureteropelvic junction obstructions can lead to impairment of renal function. Hence, the primary aim of treatment is the preservation of renal function.Material and methods: A search was carried out in the literature and consensus guidelines.Results: The currently available evidence for the treatment of ureteropelvic junction obstruction is of insufficient quality. In addition, the diagnostic combination of ultrasound and functional imaging examinations, which is decisive for the indications for a surgical intervention, do not provide reliable information about the risk of deterioration of renal function. For these two reasons, there are no generally accepted uniform guidelines. With higher grades of dilatation of the renal pelvic calyceal system (III-IV & DEG;) detected by ultrasound and an anteroposterior renal pelvis diameter > 15 mm in combination with other sonographically conspicuous criteria, a functional imaging examination is mostly carried out. A split renal function < 35-40% with delayed urinary drainage (after furosemide administration), which is estimated as being clinically important, or worsening of split renal function by > 5-10% in the further course is mostly seen as an indication for a surgical intervention. These recommendations are only applicable in patients with unilateral ureteropelvic junction obstruction without associated clinical symptoms and without further conspicuous anatomical findings in the kidneys and ureters. A partial function of the kidneys, which is clearly lower in the initial examination, should not be considered alone as a criterion for nephrectomy.Conclusion: Despite the insufficient body of evidence and the limitations of diagnostic imaging examinations, there is agreement in the available consensus recommendations. A structured ultrasound examination and the continuation of the initiated standardization of imaging examinations for a better comparison of clinical findings are urgently needed. In addition, the investigation of alternative diagnostic approaches for improved assessment of the indications for a surgical intervention is desirable.