Ectopic ureters in anorectal malformations
Sarah Hecht, MD, Duncan Wilcox, MD, Andrew Trecartin, MD, Jennifer Hall, MSN, Jill Ketzer, BA, Alberto Pena, MD, Andrea Bischoff, MD.
Children's Hospital of Colorado, Aurora, CO, USA.
Background:
Literature about ectopic ureters in anorectal malformations is limited. Repair of an anorectal malformation requires dissection near the normal or abnormal insertion of the ureters (bladder neck, posterior urethra, vagina). Knowledge of the presence and location of ectopic ureters may prevent intraoperative injury. Our aim is to describe the incidence and location of ectopic ureters in patients with anorectal malformations and to characterize associated renal anomalies.
Methods:
This is an IRB-approved retrospective study of patients with anorectal malformations and ectopic ureters identified in our colorectal database.
Results:
Of 2,283 patients with anorectal malformation, 79 (3.5%) had ectopic ureter(s). Of those, 29% had bilateral ectopic ureters. Nearly all (87%) of bilateral ectopic ureters occurred in females. Girls with cloacae with common channels >3cm and boys with recto-bladder neck fistulae were most likely to have ectopic ureter(s) (two-proportion Z test, p<0.0001 and p=0.049, respectively) (Table 1). Ectopic ureters most commonly inserted into the bladder neck (33%), vagina (15%), or urethra (13%) (Table 2). Renal dysfunction was noted in a high proportion of patients. The majority (59%) of ectopic ureters were associated with abnormalities of the ipsilateral kidney (absent kidney 6%, dysplasia 20%, hydronephrosis 33%). Interestingly, 29% of patients with unilateral ureteral ectopia had an abnormal contralateral kidney (absent kidney 12%, dysplasia 7%, hydronephrosis 10%) (Table 3). Only 22 patients (28%) had two normal kidneys, and 5 (6%) had documented renal failure with 2 (2.5%) requiring renal transplant. This compares to a transplant rate of 0.6% among anorectal malformation patients without ectopic ureter (p=0.036).
Table 1: Anorectal malformations associated with ectopic ureter
1A: Of patients with ectopic ureter(s), classification by type of anorectal malformation and statistical comparison to patients without ectopic ureter(s)
| Anorectal malformation | Ectopic Ureter(s) (%) | Z-statistic | p-value |
| Cloaca | 32 (40.5) | 2.88 | 0.004 |
| Long (>3cm) | 20 (25.3) | 4.69 | <0.0001 |
| Short (≤3cm) | 8 (10.1) | 0.51 | 0.610 |
| Unknown | 4 (5.1) | 0.24 | 0.810 |
| Bladder neck fistula | 8 (10.1) | 1.97 | 0.049 |
| Prostatic fistula | 6 (7.6) | -1.00 | 0.317 |
| Bulbar fistula | 3 (3.8) | -1.96 | 0.050 |
| Vestibular fistula | 7 (8.9) | -1.44 | 0.150 |
| No fistula | 1 (1.3) | -1.31 | 0.190 |
| Other | 22 (27.9) | -0.03 | 0.976 |
1B: Of all patients with an anorectal malformation, incidence of ectopic ureter by malformation type
| Anorectal malformation | Incidence of Ectopic Ureter(s) |
| Cloaca | 5.3% |
| Long (>3cm) | 8.9% |
| Short (≤3cm) | 2.9% |
| Unknown | 3.8% |
| Bladder neck fistula | 6.7% |
| Prostatic fistula | 2.4% |
| Bulbar fistula | 1.2% |
| Vestibular fistula | 2.2% |
| No fistula | 1.1% |
| Other | 3.4% |
Table 2: Location of ectopic ureter(s)
| Laterality | N (%) | Insertion | N (%) |
| Right | 29 (37) | Bladder neck | 28 (33) |
| Left | 21 (27) | Vagina | 13 (15) |
| Bilateral | 23 (29) | Urethra | 11 (13) |
| Unknown | 6 (8) | Caudally displaced | 9 (11) |
| Vas deferens | 2 (2.4) | ||
| Vestibule | 2 (2.4) | ||
| Uterus | 1 (1.2) | ||
| Other | 7 (8.3) | ||
| Unknown | 11 (13) | ||
Table 3: Renal anomalies in anorectal malformation patients with ectopic ureter(s)
| Kidney Function | N (%) | Kidney with ectopic ureter | N (%) | Kidney with orthotopic ureter | N (%) |
| Bilateral normal | 22 (28) | Normal | 36 (41) | Normal | 41 (71) |
| Solitary normal OR Unilateral abnormal | 34 (44) | Absent | 5 (6) | Absent | 7 (12) |
| Solitary abnormal OR bilateral abnormal | 17 (22) | Dysplastic | 17 (20) | Dysplastic | 4 (7) |
| Renal failure and/or transplant | 5 (6) | Hydronephrosis | 29 (33) | Hydronephrosis | 6 (10) |
Conclusions:
The incidence of ectopic ureter is 3.5% among anorectal malformation patients. Long common channel cloacae and recto-bladder neck fistulae have a higher incidence. Ureteral ectopia seems to confer an increased risk of renal failure. Identifying ectopic ureters is important for surgical planning and vigilant renal function monitoring is necessary when ectopic ureters are identified.
Back to 2019 Abstracts
