Although rarely indicated, patients presenting before the age of 6-12 months with distal ureteral obstruction with associated ipsilateral renal function loss / severe hydroureteronephrosis and/or febrile UTI have been traditionally managed with an end cutaneous ureterostomy. If I was asked in my boards how to deal with such a problem I would answer “cutaneous ureterostomy”. Its a big dogma in pediatric urology.
Once these patients are older than 1 year of age, a ureteral reimplantation with or without ureteral tapering is usually performed.
The outcomes of cutaneous ureterostomy were published by Kitchens et al (2007, Kitchens, J Urology). These are the outcomes for only the patients with primary distal obstruction (obstructed megaureter) in the series:
- There was an incidence of 40% (6/15) of febrile UTI while awaiting undiversion
- 4/13 (31%) required ureteral tapering at undiversion.
- 5/13 (38%) renal units developed postoperative reflux. 4 of these patients had successful Deflux and 1 had spontaneous resolution at 12 months.
- For the 13 megaureter units that had undiversion, there was a 100% reoperation rate (undiversion) plus a 31% re-reoperation rate (Deflux).
- No information was provided regarding skin problems (rashes) associated with the cutaneous ureterostomy and parent stress related to having the ureterostomy in place.
An alternative to a cutaneous ureterostomy for these infants is immediate reconstruction (reimplant with or without tapering) at the time of presentation. The outcomes of such an approach for obstructed megaureters were published by Peters et al (1989, Peters, J Urol):
- 42 megaureter repairs in infants younger than 8 months (mean age 1.8 months for prenatally diagnosed, 3.8 months for postnatal diagnosis).
- 40/42 had ureteral tailoring, all intravesical reimplants.
- 6 complications all in babies younger than 6 weeks: transient apnea in 3, UTI in 1, hyponatremia in 1 and meningitis in 1.
- 3 (7%) patient developed postoperative obstruction treated with ureteral meatotomy (1) and redo repair (2).
- Reflux occurred in 8 patients (20%). Reflux resolved spontaneously in 3 patients, was observed in 2 more and 3 patients underwent reoperation (redo reimplant)
- Overall, 14% patients had a reoperation with 86% patients having successful outcome (no reflux, no obstruction) with a single surgery.
The Following table compares the outcomes of both of these approaches:
||Primary repair at time of presentation
|Re- reoperation rate
|Success of ureteral reimplant
|Febrile UTI after first surgery
After comparing these 2 approaches, one would wonder why surgeons are still doing cutaneous ureterostomies. Greenfield et al (Greenfield, 1983, J Urol) showed even better results than Peters et al for infant (8 weeks to 6 months of age) ureteral reimplants with 97% success rates for tapered reimplants and 100% for non-tapered reimplants. Similar outcomes were published in infants less than 3 months of age by Liu et al (Liu, 1998, Journal Of Pediatric Surgery).
Some surgeons are concerned about postoperative voiding dysfunction if one does a ureteral reimplant in infancy. Laetitia et al (Laetitia, 2002, J Urol) compared pre and post-operative urodynamics in 2 groups of 25 children who had reimplantation before and after 12 months of age. There was no difference in urodynamic parameters between the groups. Ooi et al (Ooi, 2014, J Ped Urol) found to evidence of lower urinary tract dysfunction in children undergoing intravesical Cohen reimplants under one year of age.
If several series show good outcomes for infant ureteral reimplants with rare postoperative obstruction, why is the cutaneous ureterostomy still been done? The medical literature does not give any insights as to why so we are left to deliberate. One reason could be that an intravesical ureteral reimplant in a baby is technically difficult.
A refluxing extravesical reimplant as an alternative to cutaneous ureterostomy has been promoted by the group in Indiana (Kaefer, 2014, J Pediatric Urology). Although devoid of the skin complications caused by having a cutaneous ureterostomy, the refluxing reimplant suffers from similar reoperation rates and recurrent UTI’s as the cutaneous ureterostomy.
A formal Extravesical non refluxing ureteral reimplant in infancy has not been published to our knowledge. Over the past 18 months, we performed extravesical ureteral reimplants in infants with distally obstructed ureters with severe hydro (SFU 3 and 4) and evidence of decreased function and obstruction on nuclear scan (infinite curve in 3, one got DMSA so no curve, DIFFERENTIAL FUNCTION of 18, 25, 32 and 36%) in 4 consecutive patients (1 presented with urosepsis and 3 prenatally diagnosed). Ureters were not tapered and intravesical tunnels were around 3 cm in length. All were done at age 2 months. All patients underwent surgery with no postoperative complications. A stent sutured to the Foley was left for 1 week and removed in clinic. No patient has developed a postoperative UTI. Hydronephrosis was completely resolved in all the patients. 2 patients had normal postoperative VCUG and 2 had postoperative reflux which is being observed since the patients are asymptomatic 3 and 9 months after surgery.
Extravesical ureteral reimplantation might be technically easier than intravesical ureteral reimplantation in infants. Our experience indicates that is probably a much better alternative to cutaneous ureterostomy. Surgeons might be less concerned about postoperative voiding dysfunction with extravesical unilateral reimplant compared to intravesical reimplant. A multicenter prospective observation study of extravesical reimplants could help establish the reproducibility of our results and hopefully steer surgeons away from the current standard of care (cutaneous ureterostomy) which is a procedure not supported by the medical literature.
We are currently working in such a prospective study.