|Year : 2015 | Volume
| Issue : 1 | Page : 17-19
Incontinence in crossed fused kidney: A rare association
Jyoti M Bothra, Hemanshi S Shah, Shalika Jayaswal, Vikrant Kumbhar
Department of Pediatric Surgery, Byl Nair Hospita, Mumbai, Maharashtra, India
|Date of Web Publication||23-Mar-2015|
Hemanshi S Shah
Department of Pediatric Surgery, Byl Nair Hospital, Dr. A. L. Nair Road, Mumbai 400 008, Maharashtra
Source of Support: None, Conflict of Interest: None
Crossed fused ectopia is an asymptomatic fusion anomaly usually diagnosed incidentally or due to symptoms of associated urinary abnormalities. They are rarely associated with an ectopic opening of the ureter. We present a case of 6-year-old female with constant dribbling diagnosed to have left to right inferior crossed fused kidney with ipsilateral ureteral ectopy.
Keywords: Crossed fused kidney, ectopic ureter, incontinence
|How to cite this article:|
Bothra JM, Shah HS, Jayaswal S, Kumbhar V. Incontinence in crossed fused kidney: A rare association. Saudi Surg J 2015;3:17-9
| Introduction|| |
Anomalies of renal fusion are a rare entity. A kidney is called crossed fused ectopic when it lies on the side opposite to the insertion of its ureter into the bladder. It is the second most common fusion anomaly after horseshoe kidney,  found in 1:2,000 autopsy cases.  Incidence of an ectopic ureteral orifice from the crossed renal unit is 3%, however, ectopic ureteral orifice from the uncrossed renal segment is much rarer with only a few isolated cases reported in the literature. 
| Case Report|| |
A 6-year-old healthy girl presented with complaints of continuous dribbling of urine and dampness of clothes. History of continence with incontinence was obtained. Developmental milestones were normal. There was no spinal anomaly. No history of fever, chills, pyuria, hematuria or constipation. Intravenous urography [[Figure 1]] done outside showed absence of kidney in left renal fossa. Left lower ureter was seen entering bladder on the left side and coursing towards midline. The right side kidney was poorly opacified, and a massively dilated right ureter was seen. Blood investigations were within normal limits. Ultrasound confirmed empty left renal fossa with presence of a hydronephrotic renal mass on the right side with probable diagnosis of duplex moiety with ectopic ureter. Micturating cystourethrogram showed no reflux. Magnetic resonance urography (MRU) showed hydronephrotic right kidney with dilated tortuous ureter opening into the upper vagina [[Figure 2]]. Left kidney was seen fused inferiorly to the right kidney with the opening of the ureter on the left side. Computed tomography (CT) intravenous pyelogram (IVP) confirmed findings of left cross fused inferior ectopia with anterior rotation of renal pelvis with right hydronephrosis and hydroureter and an ectopic ureteral opening. A dimercaptosuccinic acid renal scan showed a differential function of 15% in the upper region (right) and 85%in crossed over lower region (left kidney) cystogenitoscopy showed a hemitrigone and absent right ureteric opening. No ectopic opening was visualized in rest of the urogenital system. The left ureteric opening was cannulated. During surgery, left inferior crossed fused ectopia was seen. The left pelvis was anteriorly rotated with a normal caliber ureter. Right renal pelvis was dilated with a dilated ectopic right ureter crossing the left renal pelvis [[Figure 3]]. As the right kidney showed a good differential function ureteropyelostomy [[Figure 4]] was done over a DJ stent placed in the upper renal pelvis. Patient had no incontinence postoperatively.
| Discussion|| |
Renal fusion anomalies are rare congenital disorders with horseshoe being the commonest and crossed fused being next. They are more common in males with a preponderance of 3:2. 
The fusion anomalies are classified as: (1) Unilateral fused kidney with inferior ectopia; (2) sigmoid or S-shaped; (3) lump or cake; (4) L-shaped or tandem; (5) disk, shield, or doughnut; and (6) unilateral fused kidneys with superior ectopia. 
Most individuals with this anomaly are asymptomatic. Symptoms generally occur in third or fourth decade of life and may include vague lower abdominal pain, hematuria, fever, hypertension, and a palpable abdominal mass. ,, In all types of fusion anomalies, the ureteral orifice associated with each kidney is usually orthoptopic. Most orthotopic renal units are normal. If an abnormality exists, it usually involves the ectopic kidney and consists of cystic dysplasia, ureteropelvic junction obstruction, reflux, nephrolithiasis, carcinoma, and ectopic ureterocele. ,
Pediatric patients are most often present with multiple congenital anomalies, especially of the skeletal system.  Kraft et al. reported a unique case of a crossed fused ectopic kidney with a vaginal ectopic ureter in a 10-year-old girl with continuous urinary incontinence.  Another rare case of crossed fused ectopia with inverted Y-ureteral duplication with ectopic ureter and bicornuate uteri was reported from Japan.  Other ectopic ureters were found in males opening into the seminal vesicles.  However, no case with ectopic ureter from the orthotopic renal unit has been reported in the literature, as seen in our case.
The cause of crossed fused is unknown. Various reasons have been put forward like pressure from abnormally placed umbilical arteries, abnormal ureteral bud development, malalignment, and abnormal rotation of the caudal end of the fetus, teratogenic factors, and genetic influences. , The embryology of ectopic ureter is postulated to be due to temporospatial discordance of ureteral budding. 
Diagnosis is generally by radiological investigations. CT IVP gives complete anatomical details. A CT angiography or MRU are helpful and of utmost importance to delineate the renal vasculature, which is usually anomalous.
Ectopic ureters are treated depending on the function of the draining moiety. Ureteropyelostomy, uretero-ureterostomy, ureteric reimplantation or nephrectomy are the various techniques used. In crossed fused ectopia nephrectomy should be planned in cases of dysplastic or nonfunctioning kidney as usually seen with ectopic ureter. Preservation of a well-functioning ectopic kidney is recommended.
| References|| |
Shapiro E, Bauer SB, Chow JS, Anomalies of upper urinary tract. Campbell Walsh Urol 2012;4;3140.
Patel TV, Singh AK. Crossed fused ectopia of the kidneys. Kidney Int 2008;73:662.
Ghosh BC, DeSantis M, Kleyner Y, Zak Y. Crossed fused renal ectopia with calculi. J Am Coll Surg 2008;206:753.
Malek RS, Utz DC. Crossed, fused, renal ectopia with an ectopic ureterocele. J Urol 1970;104:665-7.
Marandola P, Barbagli G, Rovereto B, Delle Rose A, Natali A. Crossed renal ectopia without fusion associated with hypertension: Case report with angiographic study. Rays 1986;11:41-4.
Birmole BJ, Borwankar SS, Vaidya AS, Kulkarni BK. Crossed renal ectopia. J Postgrad Med 1993;39:149-51.
Kraft KH, Molitierno JA, Kirsch AJ. Ten-year-old girl with crossed-fused ectopic kidney and ectopic ureter to vagina. Urology 2007;70:1220-1.
Liu L, Yang J, Zhu L, Yi L, Zhu B, Song W, et al.
Crossed-fused renal ectopia associated with inverted-Y ureteral duplication, ectopic ureter, and bicornuate uteruses. Urology 2010;75:1175-7.
Kumar S, Pandya S, Singh SK, Panigrahy B, Acharya N, Lal A, et al.
Laparoscopic heminephrectomy in L-shaped crossed fused ectopia. J Endourol 2008;22:979-83.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]