Ureteropelvic junction obstruction

1. Ureteropelvic junction obstruction 報告者: Intern 黃暉程Supervisor: 主治醫師: 邱元佑

2. Identification • Name: 黃小弟 • Birth date: 05/31/03 → 19 d/o • G2P2, NSD, Apgar score: 9’→10’ • GA 41weeks, BW: 3000g(10~25%) • BL: 52.5cm(10~25%), HC: 35cm(10~25%) • DOIC(-), PROM(-)

3. Chief complaint: left abdominal mass for 2 days

4. Present Illness GA 28-30wks Prenatal exam at 姚博琳’s clinic: Left hydronephrosis; Oligohydromino(-); Other abnormality(-) One mass over left abdomen noted by his mother 92/05/31 92/06/18 GA 41wks, NSD: Renal echo at 姚博琳’s clinic: Hydronephrosis is not identified Brought to Dr. 邱: A mass over LUQ palpable 92/06/16

6. One 11x7cm soft mass over left abdomen; percussion: spongy-filling

7. Abdominal mass ~ approach • Inspection, Percussion, Palpation

8. Abdominal mass by age • Age-group 1 m~1 yr After 1 yr Newborns

9. Differential diagnosis • Non-urologic Abdominal distention, pyloric stenosis, hepatosplenomegaly, intestinal obstruction, malignany, feces • Urologic Hydronephrosis, cystic disease, Wilms’ tumor, neuroblastoma, distended bladder

10. Renal echo (Jun 18) Left severe hydronephrosis Cortex thickness: about 0.2cm AP diameter: 4.48cm (>1.5cm) Right moderate hydronephrosis No parenchyma involvement AP diameter: 1.2cm (>1cm) Imp: suspect left ureteropelvic junction obstruction

11. Present Illness (1) VCUG (2) Antegrade pyelography Left PCN 92/06/18 92/06/27 92/7/2: discharge Admission PE LAB:CBC/DC, Biochemistry, U/A 92/06/19 92/06/23 (1) Left dismembered pyeloplasty (2) Pathologic Dx: Muscular hyperplasia and fibrosis, compatible with stenosis

12. Indication of PCN • Obstruction with infection • Obstruction without infection • Stone disease • Prelude to endoscopic/ interventional procedures • Delivery of medications/ chemotherapy • Urinary leaks • Urinary diversion for hemorrhagic cystitis

13. VCUG (Jun 23) Imp: No evidence of vesico-ureteral reflux

14. Antegrade pyelography:Left UPJ stenosis is considered

15. Present Illness Discharge! (1) VCUG (2) Antegrade pyelography 92/06/27 92/7/2 Left PCN 92/06/19 92/06/23 (1) Left dismembered pyeloplasty : UPJ obstruction, high insertion (2) Pathologic Dx: Muscular hyperplasia and fibrosis, compatible with stenosis

16. Whitaker test during operation • Measure the pressure gradient between the pelvis & the bladder under fixed infusion rate • Less than 12 mmHg: no obstruction • Above 20 mmHg: obstruction • Pressure gradient was 14~15 mmHg → 1. intermediate 2. good compliance of pelvis and ureter

17. Diagnosis Left UPJ stenosis

18. Discussion UPJ obstruction

19. UPJ obstruction • generally a congenital condition • male, left-sided lesions predominating • most frequently diagnosed cause of urinary obstruction in children • causes hydronephrosis which may damage the kidney

20. Pathology Various interpretations- • Preponderance of longitudinal muscle fibers • Excessive collagen fibers in & around muscle bundles • Compromised or attenuated muscle bundles Our case: moderately lymphocytic infiltration & focal suppurative inflammation

21. Symptoms & signs • Back or flank pain • UTI with fever • Hematuria • Abdominal mass→ infants }old children

22. Diagnosis & tests • Prenatal Maternal pregnancy ultrasound: hydronephrosis • Postnatal Ccr, BUN, electrolytes, AP, DTPA, MAG3, VCUG

23. Etiology • Intrinsic: Narrowed, dysfunctional or adynamic segments • Extrinsic: Upper ureter is angulated, kinked or compressed by bands or adhesions

24. Intrinsic obstruction • mechanical: narrowed→ incomplete embryological ureteric bud recanalization; muscular invaginations overdevelop as flaps or valves • functional: adynamic or dysfunctional segment → inability to initiate, form or conduct peristaltic waves across the UPJ

25. Extrinsic obstruction • vessel or fibrous band may pass anterior to the pelvis & ureter: most common • may secondary to intrinsic disturbance which produces pelvic overdistension & rotation • high insertion of the ureter into the pelvis

26. Extrinsic ~ High insertion

27. Whitaker test: flow across UPJ obstructions Pressure dependent Volume dependent Intrinsic obstructionExtrinsic obstruction

28. Treatment • influenced by renal function, infection • surgical correction of the obstruction • infants: dismembered pyeloplasty • adults: percutaneous or endoscopic technique • a nephrostomy stent is placed to drain urine until the patients heals

29. Surgical indication • Bilateral UPJO • Palpable mass • Unilateral UPJO with hydronephrosis Grade 4 (Massive pelvic & calyceal dilatation with thinned parenchyma); DTPA < 30% or worsen > 10% in f/u

30. Author and Year Patients/Kidneys Success (%) Poulsen et al, 1987 35 100 O’Reilly, 1989 30 83–93 MacNeily et al, 1993 75 85 Shaul et al, 1994 32/33 (<2 mo old) 97 30/33 (>2 mo old) 93 Salem et al, 1995 100 98 McAleer and Kaplan, 1999 79 90 Austin et al, 2000 135/137 91 Houben et al, 2000 186/203 93 Prognosis ~ pyeloplasty

31. Prognosis ~ pyeloplasty

32. Expectantions • Rapid decompression of the kidney immediately following birth can substantially improve kidney function in an infant with UPJ obstruction diagnosed before the child is born. • Most patients do well with no long-term consequences

33. Complications • Permanent loss of kidney function-renal failure • require dialysis at some point in their lives as a result of this problem

34. Thanks for your attention!