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Congenital obstruction of ureteropelvic junction — Clinical Guidelines

Overview

Congenital ureteropelvic junction (UPJ) obstruction is a condition characterized by impaired urine flow from the renal pelvis to the ureter, often leading to hydronephrosis and potential renal damage if untreated. Early intervention can prevent long-term renal sequelae. 1 4 11

Diagnosis

Key Diagnostic Criteria: Hydronephrosis, elevated renal pelvis pressure, and decreased differential renal function.

Recommended Tests: Ultrasound, voiding cystourethrogram (VCUG), and MAG3 or DMSA renal scans for functional assessment.

Grading: Society of Fetal Urology (SFU) grading system for severity based on prenatal ultrasound findings. 4 11

Management

First-Line Treatment: Open, laparoscopic, or robotic-assisted pyeloplasty for definitive surgical correction.

Minimally Invasive Approaches: Laparoscopic and robotic-assisted techniques show comparable outcomes to open surgery with reduced recovery times. 5 7 8

Endoscopic Options: Endopyelotomy for selected cases, particularly when combined with stone management. 15 17

Temporary Measures: Nondismembered pyeloplasty and ureterostomy in situ for specific scenarios requiring temporary diversion or splinting. 6 20

Stenting: Use of double-J stents post-procedure to ensure patency, with considerations for stent size and type. 9

Special Populations

Pediatrics: Early surgical intervention (often within the first year of life) is crucial to prevent renal damage. Trends show a shift towards minimally invasive techniques and day surgery approaches to minimize hospital stay and recovery time. 1 4 6

Pregnancy: Antenatally detected bilateral hydronephrosis requires careful monitoring and timely intervention post-delivery to prevent maternal and fetal complications. 3

Comorbidities: Specific considerations for patients with coexisting renal calculi or previous surgical interventions (e.g., retained foreign bodies leading to calculus formation). 14

Key Recommendations

Early Surgical Intervention: Perform pyeloplasty in pediatric patients with significant UPJ obstruction to prevent renal impairment. (Evidence: Strong 1 4)

Minimally Invasive Techniques: Prefer laparoscopic or robotic-assisted pyeloplasty over open surgery to reduce morbidity and hospital stay. (Evidence: Moderate 5 7)

Monitor and Manage Bilateral Cases: In cases of bilateral UPJ obstruction, closely monitor contralateral kidney function and consider prophylactic intervention based on predictive factors. (Evidence: Moderate 3)

Consider Endoscopic Options: For patients with coexisting stones or those unsuitable for open surgery, consider endopyelotomy as an alternative treatment modality. (Evidence: Weak 17)

Post-Operative Stenting: Utilize appropriate stenting strategies post-pyeloplasty to ensure ureteral patency and minimize complications. (Evidence: Expert opinion 9)

References

1 Rickard M, Chua M, Kim JK, Keefe DT, Milford K, Hannick JH et al.. Evolving trends in peri-operative management of pediatric ureteropelvic junction obstruction: working towards quicker recovery and day surgery pyeloplasty. World journal of urology 2021. link 2 O'Kelly F, Fernandez N, Koyle MA. Predatory publishing or a lack of peer review transparency?-a contemporary analysis of indexed open and non-open access articles in paediatric urology. Journal of pediatric urology 2019. link 3 Jiang D, Chen Z, Lin H, Xu M, Geng H. Predictive Factors of Contralateral Operation after Initial Pyeloplasty in Children with Antenatally Detected Bilateral Hydronephrosis Due to Ureteropelvic Junction Obstruction. Urologia internationalis 2018. link 4 Jiang D, Tang B, Xu M, Lin H, Jin L, He L et al.. Functional and Morphological Outcomes of Pyeloplasty at Different Ages in Prenatally Diagnosed Society of Fetal Urology Grades 3-4 Ureteropelvic Junction Obstruction: Is It Safe to Wait?. Urology 2017. link 5 Silay MS, Spinoit AF, Undre S, Fiala V, Tandogdu Z, Garmanova T et al.. Global minimally invasive pyeloplasty study in children: Results from the Pediatric Urology Expert Group of the European Association of Urology Young Academic Urologists working party. Journal of pediatric urology 2016. link 6 Polok M, Chrzan R, Veenboer P, Beyerlein S, Dik P, Klijn A et al.. Nondismembered pyeloplasty in a pediatric population: results of 34 open and laparoscopic procedures. Urology 2011. link 7 Szydełko T, Kasprzak J, Apoznański W, Tupikowski K, Pupka A, Janczak D et al.. Clavien classification of complications after 150 laparoscopic pyeloplasties. Urology 2011. link 8 Qadri SJ, Khan M. Retroperitoneal versus transperitoneal laparoscopic pyeloplasty: our experience. Urologia internationalis 2010. link 9 Soria F, Delgado MI, Rioja LÁ, Blas M, Pamplona M, Durán E et al.. Ureteral double-J wire stent effectiveness after endopyelotomy: an animal model study. Urologia internationalis 2010. link 10 Godambe SA, Boulden T. The use of an emergency physician-directed bedside ultrasound examination to clarify a diagnosis in an 8-year-old boy with chronic abdominal pain. Pediatric emergency care 2007. link 11 Van Cangh PJ. Is it always necessary to treat a ureteropelvic junction syndrome?. Current urology reports 2007. link 12 Fallon E, Ercole B, Lee C, Best S, Skenazy J, Monga M. Contemporary management of ureteropelvic junction obstruction: practice patterns in Minnesota. Journal of endourology 2005. link 13 Tan BJ, Rastinehad AR, Marcovich R, Smith AD, Lee BR. Trends in ureteropelvic junction obstruction management among urologists in the United States. Urology 2005. link 14 Johnson JE, Conlin M. Calculus formation on a retained Acucise wire. Urology 2001. link00853-0) 15 Monga M. Mini-percutaneous antegrade endopyelotomy. Techniques in urology 1999. link 16 Perez LM, Friedman RM, Carson CC. Endoureteropyelotomy in adults. Review of procedure and results. Urology 1992. link90046-y) 17 Szewczyk W, Szkodny A, Noga A, Prajsner A, Szkodny G. Endopyelotomy for ureteropelvic junction stenosis. International urology and nephrology 1992. link 18 Ono Y, Ohshima S, Kinukawa T, Sahashi M, Yamada S. Endopyeloureterotomy via a transpelvic extraureteral approach. The Journal of urology 1992. link37235-x) 19 Bagley DH, Huffman J, Lyon E, McNamara T. Endoscopic ureteropyelostomy: opening the obliterated ureteropelvic junction with nephroscopy and flexible ureteropyeloscopy. The Journal of urology 1985. link49026-4) 20 Sugita A, Ozu K, Okamura T. Ureterostomy in situ for ureteral splinting and temporary urine drainage. Journal of UOEH 1983. link 21 Butler ML. Ureteropelvic junction obstruction. Journal of clinical gastroenterology 1979. link 22 Michigan S, Whelton PK, Walsh PC. Forgotten kidney: asynchronous bilateral ureteropelvic junction obstruction. Urology 1978. link90473-9) 23 Lifland JH. Ureteropelvic obstruction of duplex kidney. Urology 1975. link90510-5)

Congenital obstruction of ureteropelvic junction