Reconfigured Colon Ureteral Substitute
The reconfigured colon substitute applies the Yang-Monti principle of detubularization and transverse retubularization to a short colonic segment (~3 cm) to bridge long ureteral defects. The resulting tube has near-ureteral caliber and minimal mucosal surface, fitting a niche where the classic ileal ureter and the Yang-Monti ileal ureter are unsuitable — particularly in renal insufficiency, prior pelvic radiation, or unavailable small bowel.[1][2][3]
Lineage
- 1996 — Pope and Koch first reported a reconfigured ascending colon segment to replace a long ureteral defect.[3]
- 2001 — Ubrig, Waldner, and Roth formalized transverse retubularized colon segments using a 3 cm ascending or descending colon harvest.[2]
- 2003 — Ubrig and Roth expanded the series to 7 patients (3 with solitary kidneys), confirming safety in renal insufficiency.[4]
- 2012 — Lazica et al. published the longest follow-up (n = 14, median 95.8 mo).[1]
Why Colon Instead of Ileum
Colon is rarely used in its native (non-reconfigured) form because of its wide caliber and large mucosal surface. Reconfiguration solves both problems and opens specific advantages over ileum:[1][2][4]
- Anatomic proximity — ascending colon lies adjacent to the right ureter, descending colon to the left, minimizing mesenteric mobilization.
- Retroperitoneal access — flank or pararectal incision, with minimal intraperitoneal dissection.
- Renal insufficiency — colon absorbs less chloride and ammonium than ileum, making it safer when Yang-Monti ileal ureter is relatively contraindicated (eGFR <40).
- After pelvic radiation — colon is often spared from a pelvic field that has damaged the ileum.
- When ileum is unavailable — short bowel syndrome, prior extensive ileal resection, IBD.
- Caliber — after reconfiguration, the tube is ureter-sized and does not require tapering.
- Less intraperitoneal trauma than ileal substitution.
Surgical Technique
The same fundamental principle as the Yang-Monti ileal ureter, with colon as the source segment:[1][2][3][4]
- Access. Flank or pararectal incision, predominantly retroperitoneal.
- Segment selection. A ~3 cm segment of ascending colon (right-sided defects) or descending colon (left-sided), chosen immediately proximal to the ureteral defect to limit mesenteric mobilization.
- Bowel continuity. Close the colonic defect primarily.
- Detubularization. Open the segment along the antimesenteric border.
- Reconfiguration. Lay the opened segment flat into a rectangular mucosal strip.
- Retubularization. Tubularize transversely over a stent, converting the short wide segment into a longer narrow tube. A 3 cm colonic segment yields ~6–8 cm of tube.
- Anastomosis. Spatulated proximal end-to-end anastomosis to renal pelvis or proximal ureteral stump; distal anastomosis to the distal ureteral stump, bladder (with or without submucosal tunnel), or afferent limb of an ileal neobladder.[1]
- Stenting. Internal ureteral stent for several weeks postoperatively.
Variations
- Pyelo-colo-cutaneostomy. Two combined reconfigured colon segments anastomosed to skin function as a modified colon conduit when bladder reimplantation is not feasible.[2][4]
- Double Monti sigmoid. Sigmoid-colon double-Monti tube combined with a Boari flap has been reported for total left ureteral substitution with stable split function at 3.25 yr.[6]
Indications
When simpler options are insufficient and ileum is unsuitable, particularly:[1][2][3][4]
- Renal insufficiency (relative contraindication to ileal substitution because of metabolic burden).
- Prior pelvic irradiation sparing the colon.
- Unavailable ileum — short bowel, prior ileal resection, IBD.
- Solitary kidney where metabolic consequences must be minimized.
- Upper and mid ureteral defects where the colon lies adjacent.
- Need for cutaneous diversion as a pyelo-colo-cutaneostomy.
Common etiologies: iatrogenic injury, malignancy, retroperitoneal fibrosis, radiation strictures.[1][7]
Long-Term Outcomes
Lazica 2012 — n = 14, median 95.8 mo (range 38–136)[1]
| Parameter | Result |
|---|---|
| Excellent renal function preserved | 10/14 (71%) |
| Stent-free at last follow-up | All 6 surviving patients (100%) |
| Obstruction of ureteral replacement | None |
| Metabolic disorders | None |
| Mucus obstruction | None |
| Stricture or adhesive ileus | None |
| Reinterventions | 7 patients required 11 reinterventions |
| Procedure-related deaths | None |
Ubrig & Roth 2003 — n = 7 (3 solitary kidneys, mean 23 mo follow-up)[4]
No complications related to the reconfigured colon segments. Two patients died of progressive disease without ureteral-substitute malfunction.
Mixed intestinal substitution — Chung 2006, n = 56 (4 colonic, mean 6 yr)[7]
Renal function preserved overall (median creatinine 1.0 mg/dL pre and post). Major complications in only 10.5%.
Complications
| Complication | Rate (Lazica n = 14) | Notes |
|---|---|---|
| Metabolic | None | Critical advantage — small mucosal surface limits absorption.[1][2] |
| Mucus obstruction | None | Minimal mucosal surface vs non-reconfigured bowel.[1] |
| Anastomotic stricture | None | [1] |
| Urinary tract infection | 3/14 (21%) | At 4 wk, 3 mo, 112 mo.[1] |
| Prolonged stenting required | 4/14 (29%) | [1] |
| Secondary drainage | 3/14 (21%) | [1] |
| Bowel obstruction | 1/14 (7%) | From peritoneal carcinosis, not the reconstruction.[1] |
| Ureteral fistula | Rare | Reported in irradiated patients in mixed reconfigured-intestinal series.[8] |
| Long-term malignancy of the bowel segment | ~0.8% (general bowel-interposition rate) | Not specifically reported in reconfigured-colon series.[9][10] |
Reconfigured Colon vs Yang-Monti Ileal Ureter vs Classic Ileal Ureter
| Feature | Reconfigured Colon | Yang-Monti Ileal Ureter | Classic Ileal Ureter |
|---|---|---|---|
| Bowel segment | ~3 cm colon | 5–7.5 cm ileum | 15–25 cm ileum |
| Surgical access | Retroperitoneal (flank) | Transperitoneal | Transperitoneal |
| Intraperitoneal surgery | Minimal | Moderate | Significant |
| Mesenteric mobilization | Minimal (colon adjacent) | Moderate | Significant |
| Renal insufficiency | Preferred | Caution (eGFR >40) | Relatively contraindicated |
| After pelvic irradiation | Often feasible | Limited if ileum irradiated | Limited if ileum irradiated |
| Metabolic complications | None reported | None reported | 3.7–4% |
| Mucus obstruction | None reported | Minimal | Significant risk |
| Antireflux reimplantation | Feasible | Feasible | Difficult |
| Long-term patency | Excellent (no obstruction at ~8 yr) | >80% | ~83% |
Onlay Variation
Reconfigured colon (or ileum) can also be used as an onlay flap rather than a circumferential interposition: the strip is laid over a preserved but strictured ureteral plate (opened longitudinally) without complete resection, sparing native ureteral tissue and blood supply. Ordorica et al. reported 100% urinary drainage in 14 of 16 renal units at mean 44 months, with only minor mucous production and no stone formation.[8]
Special Populations
- Solitary kidney. All 3 solitary-kidney patients in the Ubrig & Roth series had no complications related to the colon segment.[4]
- Cutaneous diversion needed. Pyelo-colo-cutaneostomy (two combined reconfigured colon segments to skin) functions as a modified colon conduit.[2][1]
See Also
- Yang-Monti Ileal Ureter
- Ileal Ureter (classic)
- Boari Flap with Psoas Hitch
- Renal Autotransplantation
- Upper Tract Reconstruction Principles
References
1. Lazica DA, Ubrig B, Brandt AS, von Rundstedt FC, Roth S. Ureteral substitution with reconfigured colon: long-term followup. J Urol. 2012;187(2):542–548. doi:10.1016/j.juro.2011.09.156
2. Ubrig B, Waldner M, Roth S. Reconstruction of ureter with transverse retubularized colon segments. J Urol. 2001;166(3):973–976.
3. Pope J, Koch MO. Ureteral replacement with reconfigured colon substitute. J Urol. 1996;155(5):1693–1695.
4. Ubrig B, Roth S. Reconfigured colon segments as a ureteral substitute. World J Urol. 2003;21(3):119–122. doi:10.1007/s00345-003-0320-9
5. Xiong S, Zhu W, Li X, et al. Intestinal interposition for complex ureteral reconstruction: a comprehensive review. Int J Urol. 2020;27(5):377–386. doi:10.1111/iju.14222
6. Castellan M, Gosalbez R. Ureteral replacement using the Yang-Monti principle: long-term follow-up. Urology. 2006;67(3):476–479. doi:10.1016/j.urology.2005.09.005
7. Chung BI, Hamawy KJ, Zinman LN, Libertino JA. The use of bowel for ureteral replacement for complex ureteral reconstruction: long-term results. J Urol. 2006;175(1):179–183; discussion 183–184. doi:10.1016/S0022-5347(05)00061-3
8. Ordorica R, Wiegand LR, Webster JC, Lockhart JL. Ureteral replacement and onlay repair with reconfigured intestinal segments. J Urol. 2014;191(5):1301–1306. doi:10.1016/j.juro.2013.11.027
9. de'Angelis N, Schena CA, Marchegiani F, et al. 2023 WSES guidelines for the prevention, detection, and management of iatrogenic urinary tract injuries (IUTIs) during emergency digestive surgery. World J Emerg Surg. 2023;18(1):45. doi:10.1186/s13017-023-00513-8
10. Martini A, Villari D, Nicita G. Long-term complications arising from bowel interposition in the urinary tract. Int J Surg. 2017;44:278–280. doi:10.1016/j.ijsu.2017.07.030