THE; JOURNAL OF UROLOGY
Vol. 80, No. 6, December 1958 Printed in U.S.A.
ECTOPIC URETER TERMINATING IN SEMINAL VESICLE; UNILATERAL POLYCYSTIC KIDNEY: REPORT OF A CASE AND REVIEW OF THE LITERATURE ROBERT ALLANSMITH From the Depai-tment of Surgery, Stanford University Hospital, San Francisco, Cal.
The opportunity to present an unusual genitourinary tract anomaly, to review the embryology and anatomy, and to review and summarize the literature is the basis of this report. The anomaly is characterized by an ectopic ureter terminating in the seminal vesicle and a polycystic kidney on the same side, and agenesis of the opposite kidney and ureter. The embryology and events leading to such an anomaly are discussed. Because of the close anatomical and embryological relationship between the genital and urinary systems, a congenital malformation of one is frequently associated with a congenital malformation of the other. These systems form by collecting parts arising separately and independently in time and place. Some organs appear and disappear without ever becoming functional, their parts being salvaged for a new function as part of an entirely different organ. As the caudal part of the embryo develops and elongates, the shifting of the position of the organs increases the possibilities for displacements and malformations. Thus a thorough knowledge of the embryology of the genital and urinary systems is necessary for an analysis and interpretation of the more complex congenital anomalies involving these systems. A most unusual anomaly is a unilateral polycystic kidney with the termination of the ureter in the seminal vesicle on the same side, and with agenesis of the opposite kidney and ureter. The following is the report of such a case. CASE REPORT
A stillborn male infant was delivered after 9 months' gestation. The mother had been in her usual excellent health during the pregnancy and had an uncomplicated spontaneous delivery. The family history was negative for familial diseases and congenital anomalies. The postmortem examination was performed one hour after death. The body was moderately well nourished, well preserved and weighed 5½ Accepted for publication March 20, 1958. 425
pounds. It was quite symmetrical and free of pathological changes except for a slight outward bowing of the legs and a bilateral talipes calcaneovalgus. The serosal cavities, heart, lungs, pancreas, spleen, liver, biliary tract, stomach, intestines and adrenals were normally developed and lay in their usual positions. The urinary and genital systems were severely malformed and warrant a detailed description. The left kidney and ureter were absent. The right kidney was located between the eleventh thoracic and third lumbar vertebrae and weighed 11 gm. It had the typical appearance of a severely malformed polycystic kidney and measured 4.2 by 2.3 by 2.3 cm. The two small renal arteries coming directly from the aorta entered the hilum. There was no renal artery on the left. The right ureter was identified and injected with water. It was not dilated but became tortuous at its distal end and communicated with the right vas deferens through the seminal vesicle. The right vas was traced from its communication with the right ureter near the prostate through the right inguinal ring to the right testis. When water was injected into the right ureter, the ureter, right seminal vesicle, vas deferens and epididymis were easily distended without leakage of fluid. A probe was passed easily through the urethra into the bladder. The bladder was thickwalled, tube-shaped, and did not communicate with the right ureter. The urachus was not patent. Both testes were found in the scrotum and appeared normal. The inguinal rings were patent bilaterally. The vas deferens on each side ran its normal course to the prostate passing below the neck of the bladder. There was no communication between the bladder and the rectum or between the right ureter and the rectum. Multiple sections were taken from the right kidney, the ureter, seminal vesicle, vas, epididymis, testis, prostate, rectum and bladder. The kidney was largely fibrous, with few tubules, scattered cysts and isolated, badly formed glomeruli. The pelvis and ureter were well formed,
FIG. 1. a, Polycystic right kidney; b, right ureter; c, seminal vesicle; d, bladder, prostate and rectum; e, vas deferens; f, right testis; g, gubernaculum testis.
although in some sections some of the surface mucosa was desquamated. The vas, epididymis, prostate and testes were of the infantile type. The bladder was collapsed but regularly formed. Sections of rectum were normal. There was a normal distribution of ganglion cells and nerve fibers about the prostate and lower end of the bladder. No obstruction was found between ureter and seminal vesicle although the lumen distally was very narrow.
urinary tract (fig. 1). On the right side was found a typical polycystic kidney whose ureter terminated in the right seminal vesicle rather than in the bladder trigone, the right ureter and right vas forming an almost closed but communicating tubular system. There was agenesis of the left kidney and ureter. A normal testis with a corresponding ductus deferens was seen on both sides.
SUMMARY OF AUTOPSY FINDINGS
The urinary and genital systems are associated intimately in development, structure and final relationship. Both originate from mesoderm of the
The case was that of a stillborn male infant who presented an unusual anomaly of the genito-
EMBRYOLOGY AND ANATOMY
ECTOPIC URETER: POLYCYSTIC KIDNEY
O(after migration of ureter)
FIG. 2. A and B, division of cloaca into rectum and urogenital sinus. 1, Urachus; 2, rectum; 3, mesonephric duct; 4, metanephros; 5, cloaca. C and D, migration of ureter and mesonephric duct (modified after Keibel). 1, Urogenital sinus; 2, mesonephric duct; 3, ureter.
same region and later are further united by joint use of the cloaca. 1 • 2 In the fifth or sixth week embryo the division of the cloaca into the rectum and urogenital sinus is progressing (fig. 2, A). In the illustration note that the wolffian ducts enter into that part of the cloaca which later develops into the urogenital sinus. The urogenital sinus is formed as the urorectal septum grows downward partitioning the cloaca into the urogenital sinus before and into the rectum behind. In the 11 mm. embryo there is an elongation and constriction of the urogenital sinus into two regions (fig. 2, B). The first is a vesiculourethral portion which receives the wolffian ducts and ureters and later forms the bladder and part of the urethra. The second, or phallic part, subsequently develops into the cavernous urethra. 1 Patten, B. M.: Human Embryology. Phi]a. delphia: The Blakiston Co, 1937 p. 549. 2 Arey, L. B.: Developmental Anatomy. Phila. delphia: W. B, Saunders Co., 1946, p. 265.
The enlarging bladder (vesicourethral segment) takes up more and more of the proximal end of the wolffian duct into its wall until at the encl of the sixth week this process has progressed beyond the origin of the ureters. This results in separate openings for the wolffian and ureteric ducts (fig. 2, C, D). The ureteral openings are more lateral and caudal. Continued unequal growth of bladder and urethral portions separates the ureteral and wolffian ducts and displaces the wolffian ducts caudally to open into the dorsal wall of the urethra on a hillock designated as Mi.iller's tubercle. As development progresses, the upper encl of the wolffian duct coils upon itself to form the cluctus epidiclymis. The caudal portion remains straight, and, as the ductus and terminal ejaculatory duct, extends from the epididymis to the urethra. Near the urethral openings this duct dilates to form the arn.pulla. The sacculated seminal vesicle is evaginatecl from the wall of the arnpulla in the thirteenth week. 3 3
Ibid, p. 279.
1. Congenital anomalies diagnosed clinically
Method of Diagnosis
Condition of Kidney
Hydronephrosis and pyonephrosis Ectopic double kidney Not visualized by x-ray
1. Day, R. F., 1924
Pyuria and left lumbar pain following fall
Catheterization of opening m posterior urethra. Pyelograms
Surgical removal of kidney and ureter
2. Culver, H., 1937
3. Hamer, H. G., I 25 Mertz, N. 0., Wishard, W. N., Jr., 1937 4. Minuzzi, Toressi, I 22 1940
Pyuria found on insurance examination Dysuria
Cystic mass in bladder punctured! Endoscopic drainage & catheter passed
Pain in the right hemiabdomen
5. Riha, L. W., I 19 Schmidlapp, C. J., Bosworth, L., 1946 6. Engel, W. J., 1948 I 21
7. Hamilton, G. R., I 20 Peyton, A. B., 1950 8. Meisel, H.J., 1952 I 28
Abdominal pain and hematuria following trauma
Squeezing sensation in rectum
Left flank pain and pyuria following injury
9. O'Malley, J. F., 27 I L Hematuria and hemaRpermia Bumgarner, J. E., 1953 10. Pasquier, C. M., I 26 I R I Enuresis Womack, R. N ., 1953
Deformity of posterior urethra on cystoscopy. Pyelograms
Ejaculatory ducts catheterized
Surgical removal of double Double kidney with upper kidney kidney abnormal Surgical removal of kid- Double kidney ney, ureter and sem. with upper ves. kidney hydronephrotic Hypoplastic None
Opening in posterior urethra catheterized and x-ray studies Cystic mass in bladder punctured Surgical removal of kid- Hypoplastic & catheter passed for pyeloney, ureter and sem. ves. grams Vasoseminal vesiculography Surgical removal of kid- Hypoplastic ney, ureter and sem. ves. Excretory urography Vasectomy I Hypoplastic
Cystic mass in bladder punctured! Surgical removal of kid- I Hypoplastic and catheter passed for pyeloney, ureter and sem. ves. grams·
11. Varney, Ford, l!J53 12. Gartman, E., Cline, W. A., 1954 13. Goldstein, A. E., Heller, E., 1955 14. Young, J. N., 19,55 15. Von S. Rummelhardt, 1955
L I Perinea! discomfort and ejacuL
latory distress Pain in back, difficult urination and nocturia
Difficulty passing urine and a split stream Perinea! pain and dysuria
Hypogastric pain and fever
Transvesical injection of cyst plus cannulation of vas. def. Cystoscopy and catheterization of opening in prostatic urethra
Surgical removal of ureter and sem. ves. Surgical removal of kidney and ureter
Surgical removal of kid- Hypoplastic ney, ureter and sem. ves. Surgical removal of ureter Absent
Cystoscopy and surgical expl oration Surgical exploration
Surgical removal of ureter and sem. ves.
0 "CJ H
I ,,. -1.
,,i It //
Frn. 3. A and B, reconstruction of anomalous development of genitourinary system. A, normal development until third week. B, a genesis of left metanephric duct. 1, Pronephros; 2, mesonephros with nephrastomes; 3, mesonephros without nephrastomes; 4, allantois; 5, mesonephric duct; 6, right metanephric duct; 7, agenesis. C, incomplete absorption of lower end of wolflian duct by enlarging bladder leaving ureteral opening attached to wolflian duct. D, anomaly at birth. However, the last word has not been written and leading authorities disagree on the development of the definitive relations between the ureters and genital structures. The disappearance of the terminal part of the wolflian ducts and the process resulting in the separation of the orifices of the ureters and wolffian ducts are still the subject of much debate. 4 Concerning the disap4
Wesson, M. B.: Tr. Am. A. Genito-Urin.
Stug., 25-27: 119-130, 1932-34.
pearance of the terminal part of the wolffian ducts, Mihalkovics and Keibel 5 believe that there is infundibular expansion and incorporation of the duct in the sinus wall. An alternate view suggested by Hertwig and supported by Lichtenberg, Chwalla and Gruber 6 explains the separation by a septum forming at the angle from which the 5 Keibel, F.: Arch. Anat. u. Entwicklungsgesch, 1896, pp. 55-156. 6 Chwalla, R.: Ztschr. f. Anat. u. EntwickJungsgesch, 83: 615, 1957.
ECTOPIC URETER. POLYCYSTIC KIDNEY
ureter issues. As for the separation of the orifices of the ureters and wolflian ducts, the view regarding a localized process of growth in the posterior sinus wall conflicts with theories describing an upward migration of the ureteric rudiment or a descent of the wolffian duct by absorption of that duct in the sinus epithelium and a subsequent secondary penetration at a new spot. The conflicting observations may arise from the study of these processes occurring differently in the several mammalian forms studied. Gyllensten7 has studied forty-two human embryos and he presents an excellent review of the developmental anatomy. An attempt has been made to account for a ureter emptying into the seminal vesical by reconstructing the steps in the developmental anatomy (fig 3). Development of the pronephros and mesonephros proceeded symmetrically and normally (fig. 3, A). The agenesis of the left kidney and ureter can be accounted for by an anomaly in the next stage of development (fig. 3, B). Note the agenesis of the left ureteric bud from the wolffian duct demonstrated in the illustration by clotted lines. The metanephrogenic mass will not differentiate to form a kidney unless the ureteric diverticulum grows into it. The persistent communication between the right ureter and the right vas at the seminal vesicle is the result of incomplete absorption of the proximal end of the wolffian duct leaving the ureteral opening attached to the wolffian duct at the site of the seminal vesicle anlage (fig. 3, C). The anomaly at birth (fig. 3, D) has been described in detail above. In the illustration the absent left kidney and ureter are again represented by clotted lines. The left ureter is drawn in its normal position terminating in the trigone of the bladder. Compare its course with that of the anomalous right ureter. Abeshouse 8 described five embryological defects resulting in ectopic ureteral orifices: 1) JVIaldevelopment of the urorectal septum resulting in the ectopic opening of the ureter into the rectum or cloaca. 2) Maldevelopment of the urogenital sinus 7 Gyllensten, L.: Development of wolflian ducts and ureters. Acta Anatomica Basie, 7: 305-344,
1949. 8 Abeshouse, B. S.: Rare case of ectopic meter opening into uterus and review of literature. Urol. & Cutan. Rev, 47: 447-465, 1943.
(especially of the vesicourethral anlagen) resulting in an ectopic opening into the bladder. 3) Failure of normal shifting process involving the ureteric buds and terminal portion of the wolffian ducts. There may be an ectopic opening into any organ derived from the terminal portion of the wolffian duct. Failure of a normal shift of the ureteral orifice results in an ureteral bud higher or seminal vesicle lower on the wolffian duct. Failure of the shifting process of the ureteral bud produces a ureter which enters the ejaculatory duct. Then too, the urcteral bud may come from that portion of the wolffian duct which would have given rise to the seminal vesicle. 4) Abnormal shifting or fusion of the urcteric bud with the mi.Ulerian ducts results in an ectopic opening into the prostatic utriclc, vagina, uterus, cervix or fallopian tubes. 5) Abnormal separation of the ureteric bud and failure of the bud to open into any organ results in a blind ureter with a hypoplastic or cystic kidney. Thom9 gives the distribution of ectopic ureteral openings in the male and female : lVf ale
Prostatic urethra Seminal vesicles Vas deferens Ejaculatory duct
33 17 6 5
Urethra Vagina Uterus Vestibnlum
37 32 3 45
REVIEW OF CLINICAL CASES IN THE LI'l'ERA'I'URE
Ectopic ureter opening into the seminal vesicle is a rare anomaly having been reported in only 15 clinical cases and in 23 autopsy reports, and these are summarized in tables 1 and 2. In an intensive review of the literature no genitourinary anomaly was found identical to the one reported. Von Ekesparre reported an ectopic ureteral orifice opening into the seminal vesicle with agenesis of the opposite kidney and ureter but there was no polycystic kidney. A.genesis of the abdominal musculature was an additional finding in his report. A survey of similar anomalies reveals that the kidney drained by the ectopic ureter is usually hypoplastic or "atrophic." Occasionally there are double kidneys and in these instances the upper part is drained by the ectopic ureter and is abnormal. The lower half drained by a normal 9
Thom, B., Ztschr. f. Urol., 22: 417-468, 1928.
2. Congenital anomalies diagnosed at autopsy
1. Thiersch 2. Hoffman, C.
Single ureter opening into seminal vesicle Bilateral double ureter. One opened normally into bladder
Right kidney missing Upper part of right kidney hydronephrotic
3. Hoffman, C.
5. Bostroem 6. Weigert
Left ureter united with vas to form sem. ves.l Left kidney double; lower part normal Left ureter entered bladder wall and commu- Left kidney atrophic nicated with sem. ves. Left ureter dilated, entering dilated sem. ves.l Left kidney absent Left ureter dilated and communicated with Left kidney cystic left sem. ves.
Right ureter dilated. Only anlage of left found Left kidney absent with sem. veR. Left accessory ureter opened into sem. ves. Left kidney atrophic Dilated left ureter cystic in wall of bladder Left kidney atrophic and opened into sem. ves. Right ureter dilated. Left dilated and opened Right pyonephrosis. Left into sem. ves. atrophic Left ureteral diverticulum. Left ureter opened Left atrophic into sem. ves. Right ureter emptied into sem. ves. Right kidney absent
Cordlike left ureter opened into sem. ves.
15. Engel 16. Erlanger
Blind, cordlike left ureter entered the sem. ves. Right ureter opened into sem. ves. Partially obliterated left ureter entered sem. ves. Dilated right ureter entered sem. ves. Dilated single ureter entered sem. ves. Accessory dilated ureter entered sem. ves.
8. Palma !l. Sankott
17. Gruber 18. Zimmerman 19. Gruber, G.
R L L
Right vas deferens ended blindly Right vas deferens thickened & opened into ejaculatory duct in its midportion
Right hypertrophic and chronic glomerulonephritis was found. Lt. atrophic Left kidney absent Right kidney missing Left kidney rudimentary Right kidney atrophic Left kidney atrophic
Seminal vesicles communicated through a common ejaculatory duct Seminal vesicles opened into a common ejaculatory duct
Two bladder diverticula Left trigone missing
Left trigone missing Right trigone missing. Right tes ticle and epididymis missing Left half of trigone missing
Left half of trigone missing No ejaculatory duct
20. McKirdie and Polke)' 21. Dreschel 22. Rech 23. Von Ekesparre
24. Smith, R. A.
Stillborn Fetus Stillborn Fetus
Left ureter entered sem. ves.
Right ureter entered sem. ves. Both left ureters opened into dilated left sem. ves. One ureter entered sem. ves. Opposite ureter a plastic
Right ureter entered sem. ves. Opposite ureter aplastic
Left kidney atrophic and calcified Right kidney hypoplastic
One kidney absent (corresponding to aplastic ureter) Right kidney multicystic. Lt. kidney a plastic
Agenesis of abdominal musculatm e
..,. C;J C;J
ureter is usually a normal functioning kidney. At surgery, a heminephrectomy is sufficient. There is no explanation for the marked prevalence for the anomaly to occur on the left. It is also interesting to note that in the thirty-nine cases reviewed, not one was bilateral. EXPERIMENTALLY PRODUCED ANOMALIES
Wilson, Roth and vVarkany10 studied two hundred and sixty-one late-fetal or newborn rats from mothers maintained on vitamin A deficient diets. Lack of dilatation of the pelves or calyces and histologic signs of parcnchymal immaturity were found in36 per cent. The administration of a single dose of vitamin A on clays 13, 14 or 15 of gestation reduced the incidence of most developmental anomalies of the kidneys, and all were prevented by treatment on the tenth, eleventh or twelfth clays. Thirty-six per cent of offspring from vitamin A deficient mothers had ectopic ureters and 90 per cent of an earlier group of selected animals had similar anomalies of the ureters. The termination of the ureters was always at some point from the place where it first appeared on the mesonephric duct to the upper segment of the urogenital sinus (urethra). Monie, Nelson and Evans11 studied pteroylglutamic acid deficiency in gestation of rats. Defects found in 66 per cent of the 21 clay embryos were renal hypoplasia, ureteric atresia, closure of the orifices of the ureters and urethral atresia, suggesting that the fundamental disturbance in the urinary system of these embryos is arrest or retardation of normal developmental processes. The combination of renal hypoplasia, ureteral ectopia, etc., in these experimental studies is very similar to the combination of abnormal findings in the cases reviewed in this report on humans. Perhaps more information concerning the events leading to a particular anomaly could be gained from study of experimentally produced abnormalities in embryos. 10 Wilson, J. G., Roth, C. B. and Warkany, J.: Analysis of syndrome of malformations induced by maternal vitamin A deficiency. Am. J. Anat.,
92: 189-217, 1953.
Monie, I. W., Nelson, M. M. and Evans, H. H.: Abnormalities of urinary system in rat embryos of pteroylglutamic acid deficient mothers. Anat. Rec., 120: 119-13.5, 1954. 11
An unusual developmental anomaly of the genitourinary system is reported. It is characterized by an ectopic ureter terminating in the seminal vesicle and a unilateral polycystic kidney on the same side, and agenesis of the opposite kidney and ureter. The embryology and events leading to such an anomaly are discussed. An extensive review of the literature has been made and summarized. REFERENCES TO CLINICAL AND AUTOPSY CASE REPORTS BACRACH, R.: Uber kongenitale Beldungsfehler des Harnapparates. Ztschr. f. Urol., 3: 921926, 1909.
BARGE, P.: Anurie detant de dix j ours. Bull. Soc. frarn,. d'urol., pp. 184-189, Apr. 27, 1936. BosTROEM, E. L.: Contributions to the pathological anatomy of the kidneys. Beitr. z. !din. Chir., 15: 159-2'14, 1895. CAMPBELL, l\1. F.: Ectopic ureteral orifice. Surg., Gynec. & Obst., 64:_22-29, 1937. CULVER, H.: Extravesical ureteral opening into the genital tract in a male. Tr. Am. A. Genito-Urin. Surg., 30: 295-300, 1937. DAY, R. F.: Ectopic opening of a ureter in a male: Report of a case. J. Urol., 11: 239-258, 1924.
DRECHSEL, J.: Jahrb. Univ. Sofia, Med. Fae., 11: 121-130, 1932.
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ENGEL, D.: Uber eine seltenere Form der Urogenitalmiszbildung. Ziegler's Beitr. z. path. Anat., 67: 549-554, 1920. ENGEL, W. J.: Ureteral ectopic opening into the seminal vesicle. J. Urol., 60: 46-49, 1948. EsPINGER, H.: Uber Angenesie der Nieren. E. Klebs Handbuch der pathologeschen Anatomie. Berlin: Hirschwald, 1869-80, vol. 2, p. 118.
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HAMER, H. G., MERTZ, H. 0. AND WISHARD, w. N., JR.: Opening of the ureter into the seminal vesicle, Tr. Am. A. Genito-Urin. Surg., 30: 301-307, 1937.
ECTOPIC URETER: POLYCYSTIC KIDNEY
HAMILTON, G. R. AND PEYTON, A. B.: Ureter opening into seminal vesicle complicated by traumatic rupture of the only functioning kidney. J. Urol., 64: 731-735, 1950. HOFFMAN, C. E.: Zuei Falle von Tiefer Mundung des greters. Correspondenz-Blatt for schweizer Arzte, 1: 147, 1871. HOFFMAN, C. E.: Zuei Falle von Umwandlung cler Samenblasen in Harnleiter. Archiv cler Heilkuncle, 13: 532-544, 1872. McKIRDIE, M. AND PoLKEY, H.: Extravesica! ureteral opening into seminal vesicle. J. Urol., 37: 706--714, 1937. MrnIZZI, P. G. AND ToRRESI, S.: Complete double kidney with hydronephrosis of the upper kidney whose ureter terminates in the seminal vesicle. Rev. argent. de uroL, 11: 152, 1940. MEISEL, H. J.: Ectopic ureter opening into a seminal vesicle. J. Urol., 68: 579-583, 1952. O'MALLEY, J. F. AND BuivIGARNER, J.E.: Ureteral ectopia as a cause of chronic infection. J. Urol., 73: 235-237, 1955. PALMA, P.: Zur pathologischen Anatomic der Bildunganomalie un uropoietischen Systems. Prager medizinische W ochenschrift, Hi: 32, 33, 367, 379, 1891. PAPIN, E. AND VERLIAC, H.: Aplasie renale gauche congenitale avec abouchment de l'uretere clans la vesicule seminale. 9: 431433, 1920. PASQUIER, C. M. AND WoMACK, R. K.: Ectopic opening of ureter into seminal vesicle. J. Urol., 70: 164-167, 1953. RECH, W.: Uber eine eigenttimliche kombinierte Misfbilclung des mannlichen urogenitalapparates und ihre formale Genese. Ztschr. f. urol. Chir., 11: 6, 1923. RELIQUET: Persistance du canal de Muller; hydronephrose de rein et de l'uretere droit; pyelonephrite calculeuse du ren gauche trea
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