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Pyeloplasty Workup

  • Author: Thomas MT Turk, MD; Chief Editor: Bradley Fields Schwartz, DO, FACS  more...
 
Updated: Dec 29, 2015
 

Laboratory Studies

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  • Laboratory studies in the evaluation of a patient with a possible or known ureteropelvic junction (UPJ) obstruction include routine serum chemistries with measurement of BUN and creatinine, urinalysis, and urine culture. Kidney function, as indicated by the BUN and creatinine values, may be normal or elevated (indicating impairment of renal function) depending on the function of the affected and contralateral kidney.
  • Prior to surgical repair, obtain a CBC count and coagulation studies as indicated. One would not expect abnormalities in the CBC count directly related to the UPJ obstruction unless kidney function is severely compromised or an active infection is present. Measures should be taken to correct any abnormality prior to surgical repair. Abnormalities of coagulation parameters would most likely be unrelated to the UPJ obstruction. Uncorrected coagulopathy is a contraindication to surgical repair, and thus, referral to an internist or hematologist would be appropriate before undertaking surgical treatment.
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Imaging Studies

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  • Renal ultrasound is usually the first test ordered in children with a urinary tract infection. Also, it is often obtained in combination with an abdominal ultrasound in adults with abdominal pain of unclear etiology.
    • Regardless of the indication for renal ultrasonography, the findings of moderate-to-severe hydronephrosis of the renal pelvis and calyces without concomitant hydroureter are indicative of UPJ obstruction.
    • If the UPJ obstruction has existed untreated for some time, a thin renal parenchyma may also be apparent.
  • In the past, the primary study obtained in adults with a clinical presentation suggestive of renal obstruction has been the intravenous pyelogram (IVP).
    • In a patient with UPJ obstruction, the initial finding from an IVP is a delayed nephrogram that may persist for 24 hours or longer.
    • Later images demonstrate gradual filling of the collecting system up to the level of obstruction of the urinary tract. The time delay to this opacification is directly proportional to the degree of obstruction.
    • Additionally, the amount of hydronephrosis correlates to the completeness and duration of the UPJ obstruction.
    • Other findings from an IVP indicative of UPJ obstruction include pyelosinus extravasation and pyelovenous backflow. Pyelosinus extravasation at a ruptured fornix can occur and may correlate with improvement in a patient's symptoms, although the obstruction itself may not have resolved. Pyelovenous backflow may also occur during an acute episode of UPJ obstruction.
  • An abdominal and pelvic CT scan with and without contrast is often the first imaging study obtained in adults who present with abdominal or flank pain because of the speed and efficacy at establishing both nonurologic and urologic causes of such pain.
    • Although it is not the first-line test for the diagnosis of UPJ obstruction, the images from a contrast CT scan are analogous to the images from an IVP of a patient with UPJ obstruction.
    • The noncontrast images demonstrate hydronephrosis without hydroureter and may also demonstrate decreased renal size and parenchymal thickness.
    • If intravenous contrast is administered, the affected kidney usually demonstrates delayed cortical and excretory phases, which correlate to the delayed nephrogram and excretory phases of an IVP.
    • The UPJ obstruction is often demonstrated by the marked delay of the passage of contrast from a hydronephrotic renal pelvis proximally to a nondilated distal ureter.
    • The severity of a UPJ obstruction may prevent any enhancement of the affected kidney during the time of the CT scan. In this instance, a delayed radiograph of the kidneys, ureters, and bladder many hours later may also demonstrate the UPJ obstruction.
    • The presence of crossing vessels, an extrinsic cause of UPJ obstruction, may also be apparent on the contrast images of a CT scan. Three-dimensional reconstruction of the CT scan for clarification of the vascular anatomy is of particular value when preoperatively evaluating anomalous renal units such as horseshoe kidneys.
  • Although not widespread as yet, the use of magnetic resonance imaging to diagnose and direct therapy of UPJ obstruction will likely increase in the future.
    • Magnetic resonance urography (MRU) offers advantages over more conventional imaging modalities because it does not use ionizing radiation and its contrast agents do not cause allergic reactions.
    • Further, MRU has recently been demonstrated to have a very high sensitivity for helping detect UPJ obstruction.
    • Magnetic resonance angiography is also a useful method to help evaluate for the presence of a crossing vessel at the UPJ, which is an important consideration during endoscopic approaches to the repair of UPJ obstruction.
  • The premier radiographic test to confirm the diagnosis of UPJ obstruction is a diuretic renogram. This study entails the administration of a radiopharmaceutical tracer such as technetium Tc 99m mercaptoacetythiglycine (MAG-3) or technetium Tc 99m diethylenetriaminepentaacetic acid (DTPA).
    • The concept of a "well-tempered" renogram involves adequate patient hydration with a combination of oral and intravenous fluids, as well as bladder catheterization for continuous drainage throughout the study.
    • The MAG-3 diuretic renogram is the criterion standard test because the agent is secreted by the renal tubules. This enables an interpretation of both the relative function of each kidney and the presence of any urinary tract obstruction, including UPJ obstruction
    • The DTPA diuretic renogram findings can also lead to a diagnosis of UPJ obstruction, but this agent does not measure tubular function because it is only filtered at the glomerulus and not secreted by renal tubules. Thus, no determinations can be made regarding relative renal function.
    • Additionally, conditions that inhibit the glomerular filtration rate, such as the renal immaturity of neonates or other nephropathies (eg, diabetic nephropathy), may make interpretation of DTPA renogram findings difficult.
    • As implied by its name, a diuretic agent, such as furosemide, is administered during the study. Furosemide is a loop diuretic, with peak effect occurring 15-18 minutes after administration. Although the exact regimen may vary by institution, the classic well-tempered renogram involves the administration of the diuretic agent 20 minutes after the radiopharmaceutical agent is administered.
    • Under this protocol, the initial images and the corresponding tracer counts indicate relative renal function. In unobstructed systems, the secretion and passage of MAG-3 to the bladder is visualized. In an obstructed urinary tract, such as in UPJ obstruction, the secretion and passage of the tracer is delayed.
    • At 20 minutes, the furosemide is administered and further images are obtained.
      • If the tracer clears with the induced diuresis, obstruction can be excluded.
      • If the tracer does not clear, then the images demonstrate continued holdup of the tracer.
      • The corresponding renogram curve also demonstrates the poor clearance of the tracer from the renal pelvis.
      • From these curves, the reaction half time (t1/2) of the clearance of the pharmaceutical tracer can be determined.
      • The upper limit of normal t1/2s has been determined to be either 10 or 15 minutes.
      • Obstructed systems have t1/2s greater than 20 minutes.
      • Systems with t1/2s between 10 and 20 minutes are deemed indeterminate.
  • Although not necessary to establish the diagnosis of UPJ obstruction, retrograde pyelograms and antegrade pyelograms may both help confirm the presence of obstruction.
    • An antegrade pyelogram may be obtained if the patient presented with an infection that required nephrostomy tube placement. Once the infection has cleared, the administration of contrast through the nephrostomy tube demonstrates the same hydronephrotic collecting system and UPJ obstruction that is seen on IVP findings.
    • Similarly, a retrograde pyelogram demonstrates similar findings. Retrograde pyelography is often performed immediately prior to the definitive repair of a UPJ obstruction in the operative suite to help confirm the site of obstruction and to help rule out any other concomitant obstruction that may be present in the urinary tract.
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Diagnostic Procedures

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  • In those cases that are indeterminate, a Whitaker test may be appropriate to establish the diagnosis of UPJ obstruction. The idea of the test is that obstruction produces a constant impediment to the flow of urine that requires an elevated pressure gradient to drive these higher flow rates. Therefore, the test attempts to measure this elevated pressure gradient.
    • The Whitaker test requires a nephrostomy tube and the ability to simultaneously measure intrapelvic and cystometric pressures.
    • Once these devices are present, fluid is administered via the nephrostomy tube at a pressure sufficient to establish a flow rate of 10 mL/s, and the resulting pressure gradient between the renal pelvis and the bladder is measured.
    • Whitaker proposed ranges of normal pressure differential as high as 12 cm water and obstructive pressure differentials greater than 20 cm water.
    • Although this test is helpful, it frequently is not obtained in clinical practice because it is highly invasive and often requires anesthesia.
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Histologic Findings

The histologic findings at the UPJ can be variable, depending on the etiology of the obstruction. In general, derangement of the normal architecture is thought to exist with an increase in collagen, atrophy, or abnormal arrangement of smooth muscle cells and aberrant innervation. The net result of the changes can result in a functional, but not a structural, obstruction. The abnormal segment can lack the normal peristaltic ability of the ureter and produce the normal passage of urine across the narrowed segment.

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Contributor Information and Disclosures
Author

Thomas MT Turk, MD Associate Professor, Department of Urology, Loyola University Medical Center

Thomas MT Turk, MD is a member of the following medical societies: American Urological Association

Disclosure: Nothing to disclose.

Coauthor(s)

Brant R Fulmer, MD Consulting Staff, Department of Urology, Geisinger Medical Center Urology

Brant R Fulmer, MD is a member of the following medical societies: Alpha Omega Alpha, American Urological Association

Disclosure: Partner received honoraria from Intuitive Surgical for speaking and teaching.

Anthony J Polcari, MD Staff Physician, Department of Urology, Loyola University Medical Center

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Chief Editor

Bradley Fields Schwartz, DO, FACS Professor of Urology, Director, Center for Laparoscopy and Endourology, Department of Surgery, Southern Illinois University School of Medicine

Bradley Fields Schwartz, DO, FACS is a member of the following medical societies: American College of Surgeons, Society of Laparoendoscopic Surgeons, Society of University Urologists, Association of Military Osteopathic Physicians and Surgeons, American Urological Association, Endourological Society

Disclosure: Nothing to disclose.

Additional Contributors

Peter Langenstroer, MD Associate Professor, Department of Urology, Medical College of Wisconsin

Peter Langenstroer, MD is a member of the following medical societies: American Urological Association

Disclosure: Nothing to disclose.

Acknowledgements

Sameer K Sharma, MD Staff Physician, Department of Urology, Loyola University Medical Center

Disclosure: Nothing to disclose.

References
  1. Helin I, Persson PH. Prenatal diagnosis of urinary tract abnormalities by ultrasound. Pediatrics. 1986 Nov. 78(5):879-83. [Medline].

  2. Blanc T, Koulouris E, Botto N, Paye-Jaouen A, El-Ghoneimi A. Laparoscopic pyeloplasty on horseshoe kidney in children. J Urol. 2013 Oct 16. [Medline].

  3. Naitoh Y, Kawauchi A, Kamoi K, Soh J, Hongo F, Okihara K, et al. Nephrolithotomy Performed Concurrently With Laparoendoscopic Single-site Pyeloplasty. Urology. 2013 Oct 19. [Medline].

  4. Atwell JD. Familial pelviureteric junction hydronephrosis and its association with a duplex pelvicaliceal system and vesicoureteric reflux. A family study. Br J Urol. 1985 Aug. 57(4):365-9. [Medline].

  5. Dietl J. Wandernde nieren und deren einklemmung. Wien Med Wochenschr. 1864. 14:153.

  6. Schuessler WW, Grune MT, Tecuanhuey LV, Preminger GM. Laparoscopic dismembered pyeloplasty. J Urol. 1993 Dec. 150(6):1795-9. [Medline].

  7. Lantz AG, Ordon M, Pace KT, Honey RJ. Prone Versus Supine Lasix Renal Scan to Assess Surgical Success After Laparoscopic and Robot-Assisted Pyeloplasty. J Endourol. 2013 Oct 9. [Medline].

  8. Ferroni MC, Lyon TD, Rycyna KJ, Dwyer ME, Schneck FX, Ost MC, et al. The Role of Prophylactic Antibiotics after Minimally Invasive Pyeloplasty with Ureteral Stent Placement in Children. Urology. 2015 Dec 9. [Medline].

  9. Jabbour ME, Goldfischer ER, Klima WJ, et al. Endopyelotomy after failed pyeloplasty: the long-term results. J Urol. 1998 Sep. 160(3 Pt 1):690-2; discussion 692-3. [Medline].

  10. Sundaram CP, Grubb RL 3rd, Rehman J, Yan Y, Chen C, Landman J, et al. Laparoscopic pyeloplasty for secondary ureteropelvic junction obstruction. J Urol. 2003 Jun. 169(6):2037-40. [Medline].

  11. Basiri A, Behjati S, Zand S, Moghaddam SM. Laparoscopic pyeloplasty in secondary ureteropelvic junction obstruction after failed open surgery. J Endourol. 2007 Sep. 21(9):1045-51; discussion 1051. [Medline].

  12. Moon DA, El-Shazly MA, Chang CM, Gianduzzo TR, Eden CG. Laparoscopic pyeloplasty: evolution of a new gold standard. Urology. 2006 May. 67(5):932-6. [Medline].

  13. Mufarrij PW, Woods M, Shah OD, Palese MA, Berger AD, Thomas R, et al. Robotic dismembered pyeloplasty: a 6-year, multi-institutional experience. J Urol. 2008 Oct. 180(4):1391-6. [Medline].

  14. Alcaraz A, Vinaixa F, Tejedo-Mateu A, et al. Obstruction and recanalization of the ureter during embryonic development. J Urol. 1991 Feb. 145(2):410-6. [Medline].

  15. Anidjar M, Mongiat-Artus P, Brouland JP, et al. Ureteral gene transfer to porcine induced strictures using endourologic delivery of an adenoviral vector. J Urol. 1999 May. 161(5):1636-43. [Medline].

  16. Bauer JJ, Bishoff JT, Moore RG, et al. Laparoscopic versus open pyeloplasty: assessment of objective and subjective outcome. J Urol. 1999 Sep. 162(3 Pt 1):692-5. [Medline].

  17. Bauer S. Anaomalies of the kidney and ureteropelvic junction. Walsh PC, Retik AB, Vaughan ED, Wein AJ, eds. Campbell's Urology. 7th ed. Philadelphia, Pa: WB Saunders; 1998. 1740-3.

  18. Bernstein GT, Mandell J, Lebowitz RL, et al. Ureteropelvic junction obstruction in the neonate. J Urol. 1988 Nov. 140(5 Pt 2):1216-21. [Medline].

  19. Biyani CS, Cornford PA, Powell CS. Ureteroscopic endopyelotomy with the Holmium:YAG laser. mid-term results. Eur Urol. 2000 Aug. 38(2):139-43. [Medline].

  20. Bomalaski MD, Hirschl RB, Bloom DA. Vesicoureteral reflux and ureteropelvic junction obstruction: association, treatment options and outcome. J Urol. 1997 Mar. 157(3):969-74. [Medline].

  21. Brown T, Mandell J, Lebowitz RL. Neonatal hydronephrosis in the era of sonography. AJR Am J Roentgenol. 1987 May. 148(5):959-63. [Medline].

  22. Canes D, Berger A, Gettman MT, Desai MM. Minimally invasive approaches to ureteropelvic junction obstruction. Urol Clin North Am. 2008 Aug. 35(3):425-39, viii. [Medline].

  23. Catalano C, Pavone P, Laghi A, et al. MR pyelography and conventional MR imaging in urinary tract obstruction. Acta Radiol. 1999 Mar. 40(2):198-202. [Medline].

  24. Clark WR, Malek RS. Ureteropelvic junction obstruction. I. Observations on the classic type in adults. J Urol. 1987 Aug. 138(2):276-9. [Medline].

  25. Corteville JE, Gray DL, Crane JP. Congenital hydronephrosis: correlation of fetal ultrasonographic findings with infant outcome. Am J Obstet Gynecol. 1991 Aug. 165(2):384-8. [Medline].

  26. Danuser H, Ackermann DK, Bohlen D, Studer UE. Endopyelotomy for primary ureteropelvic junction obstruction: risk factors determine the success rate. J Urol. 1998 Jan. 159(1):56-61. [Medline].

  27. Desai MM, Desai MR, Gill IS. Endopyeloplasty versus endopyelotomy versus laparoscopic pyeloplasty for primary ureteropelvic junction obstruction. Urology. 2004 Jul. 64(1):16-21; discussion 21. [Medline].

  28. Gill IS, Desai MM, Kaouk JH, et al. Percutaneous endopyeloplasty: description of new technique. J Urol. 2002 Nov. 168(5):2097-102. [Medline].

  29. Gleason PE, Kelalis PP, Husmann DA, Kramer SE. Hydronephrosis in renal ectopia: incidence, etiology and significance. J Urol. 1994 Jun. 151(6):1660-1. [Medline].

  30. Glenn JF. Analysis of 51 patients with horseshoe kidney. N Engl J Med. 1959 Oct 1. 261:684-7. [Medline].

  31. Hanna MK, Jeffs RD, Sturgess JM, Barkin M. Ureteral structure and ultrastructure. Part II. Congenital ureteropelvic junction obstruction and primary obstructive megaureter. J Urol. 1976 Dec. 116(6):725-30. [Medline].

  32. Johnston JH, Evans JP, Glassberg KI, Shapiro SR. Pelvic hydronephrosis in children: a review of 219 personal cases. J Urol. 1977 Jan. 117(1):97-101. [Medline].

  33. Kass EJ, Majd M, Belman AB. Comparison of the diuretic renogram and the pressure perfusion study in children. J Urol. 1985 Jul. 134(1):92-6. [Medline].

  34. Kim WJ, Yun SJ, Lee TS, et al. Collagen-to-smooth muscle ratio helps prediction of prognosis after pyeloplasty. J Urol. 2000 Apr. 163(4):1271-5. [Medline].

  35. King LR, Coughlin PW, Bloch EC, et al. The case for immediate pyeloplasty in the neonate with ureteropelvic junction obstruction. J Urol. 1984 Oct. 132(4):725-8. [Medline].

  36. Koff SA. Pathophysiology of ureteropelvic junction obstruction. Clinical and experimental observations. Urol Clin North Am. 1990 May. 17(2):263-72. [Medline].

  37. Koff SA, Campbell K. Nonoperative management of unilateral neonatal hydronephrosis. J Urol. 1992 Aug. 148(2 Pt 2):525-31. [Medline].

  38. Koff SA, Campbell KD. The nonoperative management of unilateral neonatal hydronephrosis: natural history of poorly functioning kidneys. J Urol. 1994 Aug. 152(2 Pt 2):593-5. [Medline].

  39. Lechevallier E, Eghazarian C, Ortega JC, et al. Retrograde Acucise endopyelotomy: long-term results. J Endourol. 1999 Oct. 13(8):575-8; discussion 578-80. [Medline].

  40. Louca G, Liberopoulos K, Fidas A, et al. MR urography in the diagnosis of urinary tract obstruction. Eur Urol. 1999 Feb. 35(2):102-8. [Medline].

  41. Lowe FC, Marshall FF. Ureteropelvic junction obstruction in adults. Urology. 1984 Apr. 23(4):331-5. [Medline].

  42. Maizels M, Stephens FD. Valves of the ureter as a cause of primary obstruction of the ureter: anatomic, embryologic and clinical aspects. J Urol. 1980 May. 123(5):742-7. [Medline].

  43. Matsuno T, Tokunaka S, Koyanagi T. Muscular development in the urinary tract. J Urol. 1984 Jul. 132(1):148-52. [Medline].

  44. Moore RG, Averch TD, Schulam PG, et al. Laparoscopic pyeloplasty: experience with the initial 30 cases. J Urol. 1997 Feb. 157(2):459-62. [Medline].

  45. Niemczyk P, Krisch EB, Zeiger L, Marmar JL. Use of diuretic renogram in evaluation of patients before and after endopyelotomy. Urology. 1999 Feb. 53(2):271-5. [Medline].

  46. Notley RG. Electron microscopy of the upper ureter and the pelvi-ureteric junction. Br J Urol. 1968 Feb. 40(1):37-52. [Medline].

  47. Novick A, Streem S. Surgery of the kidney. Walsh PC, Retik AB, Vaughan ED, Wein AJ, eds. Campbell's Urology. 7th ed. Philadelphia, Pa: WB Saunders; 1998. 1743.

  48. Park JM, Bloom DA. The pathophysiology of UPJ obstruction. Current concepts. Urol Clin North Am. 1998 May. 25(2):161-9. [Medline].

  49. Patel V. Robotic-assisted laparoscopic dismembered pyeloplasty. Urology. 2005 Jul. 66(1):45-9.

  50. Platt JF. Urinary obstruction. Radiol Clin North Am. 1996 Nov. 34(6):1113-29. [Medline].

  51. Recker F, Subotic B, Goepel M, Tscholl R. Laparoscopic dismembered pyeloplasty: preliminary report. J Urol. 1995 May. 153(5):1601-4. [Medline].

  52. Reddy PP, Mandell J. Prenatal diagnosis. Therapeutic implications. Urol Clin North Am. 1998 May. 25(2):171-80. [Medline].

  53. Riehle RA Jr, Vaughan ED Jr. Renin participation in hypertension associated with unilateral hydronephrosis. J Urol. 1981 Aug. 126(2):243-6. [Medline].

  54. Roarke MC, Sandler CM. Provocative imaging. Diuretic renography. Urol Clin North Am. 1998 May. 25(2):227-49. [Medline].

  55. Schwartz BF, Stoller ML. Complications of retrograde balloon cautery endopyelotomy. J Urol. 1999 Nov. 162(5):1594-8. [Medline].

  56. Segura JW. Antegrade endopyelotomy. Urol Clin North Am. 1998 May. 25(2):311-6. [Medline].

  57. Shalaby-Rana E, Lowe LH, Blask AN, Majd M. Imaging in pediatric urology. Pediatr Clin North Am. 1997 Oct. 44(5):1065-89. [Medline].

  58. Shalhav AL, Giusti G, Elbahnasy AM, et al. Adult endopyelotomy: impact of etiology and antegrade versus retrograde approach on outcome. J Urol. 1998 Sep. 160(3 Pt 1):685-9. [Medline].

  59. Stephens FD. Ureterovascular hydronephrosis and the "aberrant" renal vessels. J Urol. 1982 Nov. 128(5):984-7. [Medline].

  60. Takla NV, Hamilton BD, Cartwright PC, Snow BW. Apparent unilateral ureteropelvic junction obstruction in the newborn: expectations for resolution. J Urol. 1998 Dec. 160(6 Pt 1):2175-8. [Medline].

  61. Tawfiek ER, Liu JB, Bagley DH. Ureteroscopic treatment of ureteropelvic junction obstruction. J Urol. 1998 Nov. 160(5):1643-6; discussion 1646-7. [Medline].

  62. Thomas DF, Gordon AC. Management of prenatally diagnosed uropathies. Arch Dis Child. 1989 Jan. 64(1 Spec No):58-63. [Medline].

  63. Thorup J, Pedersen PV, Clausen N. Benign ureteral polyp as a cause of intermittent hydronephrosis in a child. J Urol. 1981 Dec. 126(6):796-7. [Medline].

  64. Turk TM, Koleski FC, Wojcik E, et al. Use of epidermal growth factor and collagen synthesis inhibition as adjuvant to healing of ureteroureteral anastomosis. J Endourol. 2000 Mar. 14(2):145-7. [Medline].

  65. Wang Y, Puri P, Hassan J, et al. Abnormal innervation and altered nerve growth factor messenger ribonucleic acid expression in ureteropelvic junction obstruction. J Urol. 1995 Aug. 154(2 Pt 2):679-83. [Medline].

  66. Whitaker RH. Clinical assessment of pelvic and ureteral function. Urology. 1978 Aug. 12(2):146-50. [Medline].

  67. Williams DI, Kenawi MM. The prognosis of pelviureteric obstruction in childhood: a review of 190 cases. Eur Urol. 1976. 2(2):57-63. [Medline].

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CT scan without contrast demonstrating severe left-sided hydronephrosis secondary to ureteropelvic junction obstruction.
Excretory urogram shows a horseshoe kidney with left hydronephrosis.
 
 
 
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