Abstract
Two cases of single system ectopic ureters both being females were managed at Sir HN Hospital, Mumbai. Single system ectopic ureters are much less common than with duplex system. The uniqueness of these 2 cases presented here is that both patients had single system ectopic ureters draining a functioning kidney. The contralateral kidney was multicystic as in case 1 and was absent as in case 2. Due to this, no urine entered the urinary bladder leading to a small capacity bladder. Ureteric reimplantation though difficult was possible, following which bladder capacity regained to normal and both the girls are now continent and without any further deterioration in renal function.

Introduction
The term ectopic ureter has typically been used to describe a ureter that inserts at or distal to the bladder neck.1 In approximately 95% of females with an ectopic ureter, the ureter inserts either into urethra or the reproductive tract.

Duplicated ectopia accounts for nearly 80% of total, while single or non-duplicated ectopia is considerably less common comprising 10-20%.2 The clinical presentation has been varied and can sometimes be misleading. The investigations for diagnosis include cystoscopy with ascending ureterogram, micturating cystourethrogram, renal scan and even videolaparoscopy.

Congenital renal and gastro-intestinal anomalies, including renal dysplasia and agenesis as well as supralevator imperforate anus and oesophageal atresia3 can be co-existing.

Management modalities differ from patient to patient, but renal preservation is of prime importance.

In children with small capacity bladder, the bladder may or may not regain its normal size and function. Also, the bladder neck and sphincter may be abnormal leading to urinary incontinence which poses a major challenge to the paediatric surgeon and the paediatric urologist.

Case 1
Two month old female child was referred for antenatally diagnosed and postnatally confirmed bilateral hydronephrosis with continuous bed-wetting. On investigating, an MCU showed a small 5 ml. capacity bladder without reflux, cystovaginoscopy showed a normal left ureteric orifice, an external orifice between normal urethral meatus and vagina leading to a tubular tract parallel to the anterior wall of vagina.

As both kidneys were markedly hydronephrotic and child was uraemic, an upper urinary diversion, i.e. bilateral high loop ureterostomies were performed. Six months later when patient settled, child was investigated further for the upper tracts. The left kidney was found to be non-functioning, multicystic kidney. Hence, a left nephroureterectomy along with a right ectopic ureteric reimplantation without submucosal tunnel was performed.

The child recovered uneventfully after undiversion and now after 2 years follow-up shows good bladder capacity, no reflux on micturating cystourethrogram, and no further renal damage.

Case 2
The second case was a female child seen at one year of age. She had low anorectal malformation with sacral agenesis and lumbar vertebral anomalies, and had undergone perineoplasty at birth. The child had urinary incontinence since then. On examination, an abnormal external orifice was visualized between external urethral meatus and vagina in the vestibule. Investigations revealed single right kidney with hydronephrosis and incomplete duplex hydroureter (Fig. 1), absent left kidney, the right ureter opening ectopically between urethra and vagina, small capacity bladder – 5 ml.(Fig. 2) and no ureteric orifice in the bladder on cystoscopy.

A right ectopic ureteric reimplantation was done without creating a submucosal tunnel as in case 1.

One and a half year later , child has good bladder capacity – 130 ml., though has right sided reflux showing incomplete triplex ureters (Fig. 3), is continent with probanthine (for uninhibited bladder contractions on urodynamic studies) and renal functions are preserved.

Fig. 1 : Ascending ureterogram showing dilated ureters with partial duplex of upper ureters and the pelvis	Fig. 2 :Micturating cystourethrogram showing catheter in the bladder and a very small capacity bladder. Also seen is sacral agenesis and lumbar vertebral anomalies.
Fig. 3 : Micturating cystourethrogram one and half year post reimplantation showing a good capacity bladder, vesico-ureteric reflux and incomplete triplication of upper ureters on right side.

Discussion
Extensive review of literature showed many studies on ectopic ureters which could be either in a duplex system or a single unduplicated system. Again both of these could affect bilateral urinary system or could exist unilaterally. An array of clinical presentation and pathology are possible. Most commonly ectopic ureters are seen with ureteral duplication in about 70-80% of cases. Of the single system ectopic ureters, the bilateral variety is more common.
Bilateral unduplicated ectopic ureters and unilateral single ectopic ureter draining a solitary kidney cause unusual problems in management due to the associated small bladder and weak or non-functional bladder neck sphincter.

Incidence of single system ectopic ureters has been variable according to studies. Gil4 reported an incidence as high as 58%, with other authors reporting 20-25%.5 In another study,5 an incidence of around 9% has been reported. It has also been noted6 that in the Western Hemisphere, most ectopic ureters are one moiety of a duplex system, but in South-east Asia, single ectopic ureters are more common.

In a study by Kesavan the bladder neck and trigone were maldeveloped in 75% of bilateral and 54% of unilateral ectopic ureters.7 As Williams notes,8 spontaneously increased capacity may occur with time and intestinal augmentation of the bladder may not be necessary.

Our finding corroborates as both the girls had gradual increase in the bladder capacity to normal.

Study conducted by Podesta9 also agrees that a majority of patients can achieve normal bladder function and capacity along with normal transurethral voiding and satisfactory continence.

Rarely, though the bladder may fail to develop adequate storage capacity and this may interfere with reconstructive efforts. Augmentation is thence necessary by either colocystoplasty or caecocystoplasty to enlarge bladder capacity.10 As reported recently,11 artificial sphincter was inserted for a female child with wide open bladder neck.

It has also been found that most commonly the side of ectopic ureter is associated with congenital renal anomalies. It is unusual to find a normal kidney with single system ectopic ureter and affected contralateral kidney.10,12 3 case reports with single system ectopic ureter and contralateral normal kidney has been presented in 1983 by Charles Sorenson.

In both of our cases, the ectopic side was hydronephrotic and the contralateral kidney was multicystic/absent which again is found to be a rare existence.

Conclusion
The bladder even though may appear small, may not necessarily be non-functional. A primary ureteric reimplantation must be performed as far as possible.

References

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