Vol. 113, February
THE JOURNAL OF UROLOGY
Printed in U.S.A.
Copyright© 1975 by The Williams & Wilkins Co.
COMMON RENAL PELVIS: A CASE REPORT JOHN G. ROSE*
AND
E. DARRACOTT VAUGHAN, JR.
From the Department of Urology, University of Virginia School of Medicine, Charlottesville, Virginia
nary tract decompensation that were thought to be secondary to reflux and the neurogenic bladder. When she was 10 months old a right cutaneous ureterostomy was done. When she was 4 years old the patient underwent a rectal pull through operation and closure of the posterior vaginal fistula. She has continued to do well without further upper tract decompensation.
Fusion of the renal pelves across the midline and drainage into a common ureter occur rarely. Burstein, 1 Kandzari and associates' and Emmett and Witten 3 reported cases in which there was fusion of the right and left renal masses, associated with an intercommunicating renal pelvis that crossed the midline and emptied into a common ureter. Potampa and associates reported a case of a common renal pelvis that crossed the midline and drained the right kidney and the lower pole of the left kidney. 4 This renal pelvis then emptied into a common ureter on the left side of the midline that crossed to insert into the right side of the bladder. The left upper pole of the kidney was drained by a single left ureter. Cass and Vitko reported a similar case of crossed renal ectopia in which an intercommunicating renal pelvis emptied into a common ureter.' We herein report a case in which there are separate renal masses on each side of the midline that are subtended by a common renal pelvis and are drained by a single ureter. CASE REPORT
S. H., U.Va. 59 69 32, a premature female infant, was the product of a normal spontaneous delivery on February 19, 1968. An imperforate anus was noted at birth. The infant was passing formed stool via the vagina. Evaluation with an excretory urogram, cystogram, vaginogram and cystoscopy confirmed the presence of an imperforate anus with a rectovaginal fistula. The patient also had partial sacral agenesis and a fused renal pelvis that drained both kidneys via a single right ureter, which was dilated and exhibited total reflux. A ureteral bud was protruding from the left side of the bladder (figs. 1 artd 2). Nephrotomograms revealed 2 separate renal units without fusion. The patient suffered multiple episodes of pyelonephritis and progressive evidence of upper uriAccepted for. publication July 26, 1974. Supported by the Mr. and Mrs. James R. McCahill Urology Research Fund. * Current address: 19 Handyboy Court, Middletown, New Jersey 07748. 1 Burstein, H.J.: Double kidney with Y-shaped ureter and ureteral calculus in an infant. Urol. & Cu tan. Rev., 42: 575, 1938. 2 Kandzari, S. J., Cha, E. M. and Milam, D. F.: Solitary fused kidney with a single Y-shaped ureter. W. Va. Med. J., 68: 181, 1972. 3 Emmett, J. L. and Witten, D. M.: Clinical Urography. Philadelphia: W. B. Saunders Co., p. 1402, 1971. 'Potampa, P. B., Hyman, M. D. and Catlow, C. E.: An unusual renal anomaly: combined tandem and horseshoe kidney. J. Urol., 61: 340, 1949. 'Cass, A. S. and Vitko, R. J.: Unusual variety of crossed renal ectopy with only one ureter. J. Urol., 107: 1056, 1972.
FIG. 1. Cystogram shows reflux into left ureteral bud and right ureter, which subtends both renal masses via intercommunicating renal pelvis. DISCUSSION
Intercommunication of the renal pelves draining both renal masses via a common ureter is a rare condition. Although the etiology of this anomaly has not been confirmed a possible and reasonable explanation can be derived from an understanding of the normal development of the upper urinary system. The ureteral bud develops as an outgrowth of the mesonephric duct after about 5 weeks of embryonic development. 6 As the portion of the mesonephric 'Koontz, W.W., Jr. and Prout, G. R., Jr.: Agenesis of the sacrum and the neurogenic bladder. J.A.M.A., 203: 481, 1968.
234
COMMON RENAL PELVIS
ft lhmal pelvis --c---+-
- - - - L !lencii pelvis '
, /
-
L Urnlerol bud
FIG. 2. Diagram of genitourinary anomalies
duct distal to the ureteral bud (the common excretory duct) is reabsorbed into the bladder wall, the ureteral orifice attains its definitive position onto the bladder trigone. While this occurs the ureteral bud grows cephalad toward the metanephric blastema and enlarges its cranial end to form an ampulla. There is a reciprocal induction between the ureteral ampulla and the metanephric blastema since the ampulla induces the development of the nephric tissue, while the latter induces the ampulla to divide. This process continues until approximately 14 weeks of development, when the major and minor calices have developed from divisions of the ureteral ampullae. Therefore, in our patient the following may be hypothesized. The left ureteral bud did develop as an outgrowth of the mesonephric duct. However, its further growth was arrested and it remained as a mere outpouching from the bladder wall. The right ureteral bud in its cephalad ascent formed its cranial end into an ampulla, which induced the metanephric blastema on the right side to develop
and then itself was induced to divide. first division was across the midline to induce the development of the metanephric blastema on left side. As ampullary branching and renal development continued the right and left systems formed, subtending each separate and these were drained by the common ureter. There does not appear to be a direct between the upper urinary tract anomalies and other congenital anomalies in our patient aside from the increased incidence of anomalies associated with bony malformation 6 and imperforate anus. 2 • 7 Gross reviewed 507 cases of imperforate anus and reported 9 cases of unilateral absence of the ureter and kidney, 7 and Kandzari's case of intercommunicating renal pelves drained by a common ureter also had an associated forate anus. 2 7 Gross, R. E.: The Surgery of Infancy and Childhood· Its Principles and Techniques. Philadelphia: W. Saunders Co., p. 356, 1953.
THE JOURNAL OF UROLOGY
Printed in U.S.A.
Copyright© 1975 by The Williams & Wilkins Co.
COMMON RENAL PELVIS: A CASE REPORT JOHN G. ROSE*
AND
E. DARRACOTT VAUGHAN, JR.
From the Department of Urology, University of Virginia School of Medicine, Charlottesville, Virginia
nary tract decompensation that were thought to be secondary to reflux and the neurogenic bladder. When she was 10 months old a right cutaneous ureterostomy was done. When she was 4 years old the patient underwent a rectal pull through operation and closure of the posterior vaginal fistula. She has continued to do well without further upper tract decompensation.
Fusion of the renal pelves across the midline and drainage into a common ureter occur rarely. Burstein, 1 Kandzari and associates' and Emmett and Witten 3 reported cases in which there was fusion of the right and left renal masses, associated with an intercommunicating renal pelvis that crossed the midline and emptied into a common ureter. Potampa and associates reported a case of a common renal pelvis that crossed the midline and drained the right kidney and the lower pole of the left kidney. 4 This renal pelvis then emptied into a common ureter on the left side of the midline that crossed to insert into the right side of the bladder. The left upper pole of the kidney was drained by a single left ureter. Cass and Vitko reported a similar case of crossed renal ectopia in which an intercommunicating renal pelvis emptied into a common ureter.' We herein report a case in which there are separate renal masses on each side of the midline that are subtended by a common renal pelvis and are drained by a single ureter. CASE REPORT
S. H., U.Va. 59 69 32, a premature female infant, was the product of a normal spontaneous delivery on February 19, 1968. An imperforate anus was noted at birth. The infant was passing formed stool via the vagina. Evaluation with an excretory urogram, cystogram, vaginogram and cystoscopy confirmed the presence of an imperforate anus with a rectovaginal fistula. The patient also had partial sacral agenesis and a fused renal pelvis that drained both kidneys via a single right ureter, which was dilated and exhibited total reflux. A ureteral bud was protruding from the left side of the bladder (figs. 1 artd 2). Nephrotomograms revealed 2 separate renal units without fusion. The patient suffered multiple episodes of pyelonephritis and progressive evidence of upper uriAccepted for. publication July 26, 1974. Supported by the Mr. and Mrs. James R. McCahill Urology Research Fund. * Current address: 19 Handyboy Court, Middletown, New Jersey 07748. 1 Burstein, H.J.: Double kidney with Y-shaped ureter and ureteral calculus in an infant. Urol. & Cu tan. Rev., 42: 575, 1938. 2 Kandzari, S. J., Cha, E. M. and Milam, D. F.: Solitary fused kidney with a single Y-shaped ureter. W. Va. Med. J., 68: 181, 1972. 3 Emmett, J. L. and Witten, D. M.: Clinical Urography. Philadelphia: W. B. Saunders Co., p. 1402, 1971. 'Potampa, P. B., Hyman, M. D. and Catlow, C. E.: An unusual renal anomaly: combined tandem and horseshoe kidney. J. Urol., 61: 340, 1949. 'Cass, A. S. and Vitko, R. J.: Unusual variety of crossed renal ectopy with only one ureter. J. Urol., 107: 1056, 1972.
FIG. 1. Cystogram shows reflux into left ureteral bud and right ureter, which subtends both renal masses via intercommunicating renal pelvis. DISCUSSION
Intercommunication of the renal pelves draining both renal masses via a common ureter is a rare condition. Although the etiology of this anomaly has not been confirmed a possible and reasonable explanation can be derived from an understanding of the normal development of the upper urinary system. The ureteral bud develops as an outgrowth of the mesonephric duct after about 5 weeks of embryonic development. 6 As the portion of the mesonephric 'Koontz, W.W., Jr. and Prout, G. R., Jr.: Agenesis of the sacrum and the neurogenic bladder. J.A.M.A., 203: 481, 1968.
234
COMMON RENAL PELVIS
ft lhmal pelvis --c---+-
- - - - L !lencii pelvis '
, /
-
L Urnlerol bud
FIG. 2. Diagram of genitourinary anomalies
duct distal to the ureteral bud (the common excretory duct) is reabsorbed into the bladder wall, the ureteral orifice attains its definitive position onto the bladder trigone. While this occurs the ureteral bud grows cephalad toward the metanephric blastema and enlarges its cranial end to form an ampulla. There is a reciprocal induction between the ureteral ampulla and the metanephric blastema since the ampulla induces the development of the nephric tissue, while the latter induces the ampulla to divide. This process continues until approximately 14 weeks of development, when the major and minor calices have developed from divisions of the ureteral ampullae. Therefore, in our patient the following may be hypothesized. The left ureteral bud did develop as an outgrowth of the mesonephric duct. However, its further growth was arrested and it remained as a mere outpouching from the bladder wall. The right ureteral bud in its cephalad ascent formed its cranial end into an ampulla, which induced the metanephric blastema on the right side to develop
and then itself was induced to divide. first division was across the midline to induce the development of the metanephric blastema on left side. As ampullary branching and renal development continued the right and left systems formed, subtending each separate and these were drained by the common ureter. There does not appear to be a direct between the upper urinary tract anomalies and other congenital anomalies in our patient aside from the increased incidence of anomalies associated with bony malformation 6 and imperforate anus. 2 • 7 Gross reviewed 507 cases of imperforate anus and reported 9 cases of unilateral absence of the ureter and kidney, 7 and Kandzari's case of intercommunicating renal pelves drained by a common ureter also had an associated forate anus. 2 7 Gross, R. E.: The Surgery of Infancy and Childhood· Its Principles and Techniques. Philadelphia: W. Saunders Co., p. 356, 1953.
