CASE REPORTS
CROSSED
RENAL ECTOPIA
FAMILIAL
OCCURRENCE”:
7’. A. HILDRETH, -4. S. CASS,
WITH
b1.D
M.B.B.S.
From the Urology St. Paul, 3Iinnesota
Service,
Gillette
(:rossed renal t-hctopia is a rare anomaly of’ the Ilrinar). tract in which one kidney crosses the nlidline to au ectopic position on the opposite side, hut its Iireter has a normal location in the hIadder. This abnormality is found once in ’ W’e have been al,~~roximateI~~ 7,500 autopsies. unable to find any previous reports of‘ this entit) oc*curring in a fimiilial pattern.
Children’s
Hospital,
(1:~
Report
An eighteen-month-old ho> \T:itll l~~rnl~~t~ myelomeningocele had torsion of the pctnis and an undescended testicle. An intravc-nt 111s pycblogram revealed crossed renal ectopia \+ith the kidneys on the right side (Fig. 1.4). L70iding cystourethrogrl\m showed no r\.idencr 01‘ refhlu. Cystoscopy rel~ealed slitlike ureteral orifiches in normal position on each side of‘ the trigone. The patient’s mother also had a c~rossc~d retlal ectopia with the kidneys located on thr, left side
(Fig. 1B). She had no spinal cord abnormality. The patient’s father was apparently normal with no urinary tract disease. There were no other siblings. The patient’s maternal grandmother also had a renal variant; on intravenous pyelogram an incomplete duplication of the left kidney was noted (Fig. 1C). Comment The embryologic basis for the development of crossed renal ectopia can be abnormal development of the metanephros or mechanical factors affecting ascent of the kidney.’ Potter’ states the outgrowth of the ureteral bud from the mesonephric duct starts early in the fifth week and lasts until the fourteenth or fifteenth week. As the ureteral bud leaves the mesonephric duct the metanephric blastema condenses around the growing end and, as the bud elongates, carries with it the enveloping blastema. If one kidney moves toward the midline, it usually also rotates anteriorly while the other remains normal. At times, fusion is so complete that a single renal mass is produced which is found most often in one renal fossa. It ordinarily receives both ureters with one ureter crossing the midline. Abnormality of the genital tract such as absence of an ovary, uterine body, cervix, and vagina in females and abnormality of the vas
deferens in the male are present in many cases. Between the sixth and eighth week of fetal life, the sexless gonad differentiates into a distinguishable testis or ovary.” It could be speculated that a common trauma during the fifth and sixth week of fetal life might result in concomitant gonadal dysgenesislagenesis and renal ma1 ascent. A review of the literature revealed no case of familial occurrence of crossed renal ectopia. ‘+ The presence of crossed renal ectopia in a mother and son is believed to be the first recorded case. No satisfactory genetic factor has been postulated so this familial occurrence is thought to be incidental. St. Paul, Minnesota 55101 (DR. CASS)
1. var,qs AD, Scardino PL. and Carlton FE. Croswd rrnal cctopia, South Med. J. 67: 1080 (197-i). 2. Potter EL: Normal and Ahnormal Development of the Kidney. Chicago. Year Book Medical Pllblishrrs. 1972. pp. 29, 102. 3. Arey LB: Drvelopmrntal Anatomy, 7th ed.. Philadrlphia. W. B. Saunders, 1974, pp. 329-341. 4. \lcDonald JH, and McCellan DS: Croswd renal wtopin, Am. J. Surg. 93: 995 (1957). 3. Aheshousr BS, and Bhisitkrd J: Crossed renal rctopia with or without fusion, Ural. Int. 9: 63 (1959). 6. Dretler SP, et (I/: The anatomic. radiologic and clinical characteristics of the pelvic kidney: tin analysis of 86 casr, J. L’rol. 105: 623 (1971).
UROLOGY
/
JULY 197X
/ \‘OLI‘XlE
XII, NUhlBEII
1
CROSSED
RENAL ECTOPIA
FAMILIAL
OCCURRENCE”:
7’. A. HILDRETH, -4. S. CASS,
WITH
b1.D
M.B.B.S.
From the Urology St. Paul, 3Iinnesota
Service,
Gillette
(:rossed renal t-hctopia is a rare anomaly of’ the Ilrinar). tract in which one kidney crosses the nlidline to au ectopic position on the opposite side, hut its Iireter has a normal location in the hIadder. This abnormality is found once in ’ W’e have been al,~~roximateI~~ 7,500 autopsies. unable to find any previous reports of‘ this entit) oc*curring in a fimiilial pattern.
Children’s
Hospital,
(1:~
Report
An eighteen-month-old ho> \T:itll l~~rnl~~t~ myelomeningocele had torsion of the pctnis and an undescended testicle. An intravc-nt 111s pycblogram revealed crossed renal ectopia \+ith the kidneys on the right side (Fig. 1.4). L70iding cystourethrogrl\m showed no r\.idencr 01‘ refhlu. Cystoscopy rel~ealed slitlike ureteral orifiches in normal position on each side of‘ the trigone. The patient’s mother also had a c~rossc~d retlal ectopia with the kidneys located on thr, left side
(Fig. 1B). She had no spinal cord abnormality. The patient’s father was apparently normal with no urinary tract disease. There were no other siblings. The patient’s maternal grandmother also had a renal variant; on intravenous pyelogram an incomplete duplication of the left kidney was noted (Fig. 1C). Comment The embryologic basis for the development of crossed renal ectopia can be abnormal development of the metanephros or mechanical factors affecting ascent of the kidney.’ Potter’ states the outgrowth of the ureteral bud from the mesonephric duct starts early in the fifth week and lasts until the fourteenth or fifteenth week. As the ureteral bud leaves the mesonephric duct the metanephric blastema condenses around the growing end and, as the bud elongates, carries with it the enveloping blastema. If one kidney moves toward the midline, it usually also rotates anteriorly while the other remains normal. At times, fusion is so complete that a single renal mass is produced which is found most often in one renal fossa. It ordinarily receives both ureters with one ureter crossing the midline. Abnormality of the genital tract such as absence of an ovary, uterine body, cervix, and vagina in females and abnormality of the vas
deferens in the male are present in many cases. Between the sixth and eighth week of fetal life, the sexless gonad differentiates into a distinguishable testis or ovary.” It could be speculated that a common trauma during the fifth and sixth week of fetal life might result in concomitant gonadal dysgenesislagenesis and renal ma1 ascent. A review of the literature revealed no case of familial occurrence of crossed renal ectopia. ‘+ The presence of crossed renal ectopia in a mother and son is believed to be the first recorded case. No satisfactory genetic factor has been postulated so this familial occurrence is thought to be incidental. St. Paul, Minnesota 55101 (DR. CASS)
1. var,qs AD, Scardino PL. and Carlton FE. Croswd rrnal cctopia, South Med. J. 67: 1080 (197-i). 2. Potter EL: Normal and Ahnormal Development of the Kidney. Chicago. Year Book Medical Pllblishrrs. 1972. pp. 29, 102. 3. Arey LB: Drvelopmrntal Anatomy, 7th ed.. Philadrlphia. W. B. Saunders, 1974, pp. 329-341. 4. \lcDonald JH, and McCellan DS: Croswd renal wtopin, Am. J. Surg. 93: 995 (1957). 3. Aheshousr BS, and Bhisitkrd J: Crossed renal rctopia with or without fusion, Ural. Int. 9: 63 (1959). 6. Dretler SP, et (I/: The anatomic. radiologic and clinical characteristics of the pelvic kidney: tin analysis of 86 casr, J. L’rol. 105: 623 (1971).
UROLOGY
/
JULY 197X
/ \‘OLI‘XlE
XII, NUhlBEII
1
