Prediction of recurrence and progression in patients with T1G3 bladder cancer by gene expression of circulating tumor cells.

OBJECTIVE: To investigate the role of gene expression of circulating tumor cells (CTCs) as noninvasive prognostic markers in patients with high risk nonmuscle invasive bladder cancer. MATERIALS AND METHODS: We identified all patients with TIG3 urothelial bladder cancer (UBC) at our institution since 2016.The study included 100 patients with T1G3 UBC and 50 healthy volunteers. CTCs were isolated from blood using immunomagnetic separation and gene expression was performed using 10 bladder cancer associated genes, namely; KRAS, EPCAM, CD133, CD44, mTOR, SURVIVIN, AKT, PI3K, VEGF, and TP53. Gene expression of CTCs was correlated to time to first recurrence and time to progression using Kaplan-Meier curves. RESULTS: There was strong negative correlation between CTCs-positive patients and time to first recurrence and time to progression. Significant differences in expression levels of specific genes were observed that can predict recurrence and progression of T1G3 UBC. CONCLUSION: CTCs appear to be noninvasive methods of predicting disease recurrence and progression in patients with high- risk nonmuscle invasive bladder cancer; therefore, studying their molecular profiling may improve prediction of recurrence and progression. Further studies are invited for more in-depth investigation to consolidate our initial results.

Endogenous BTG2 expression stimulates migration of bladder cancer cells and correlates with poor clinical prognosis for bladder cancer patients.

BACKGROUND: The B-cell translocation gene 2 (BTG2) is considered to act as a tumour-suppressor gene because of its antiproliferative and antimigratory activities. Higher levels of BTG2 expression in tumour cells have been linked to a better clinical outcome for several cancer entities. Here, we investigated the expression and function of BTG2 in bladder cancer. METHODS: The expression of BTG2 in bladder cancer cells was silenced by RNA interference. Cell motility was investigated by wound healing and Boyden chamber assays. The protein expression of BTG2 in bladder cancer was studied by immunohistochemistry. RESULTS: We observed that targeted suppression of BTG2 by RNA interference did not result in growth stimulation but led to a substantial inhibition of bladder cancer cell motility. Tissue microarray analyses of bladder cancer cystectomy specimens revealed that higher BTG2 expression levels within the tumours correlated strongly with a decreased cancer-specific survival for bladder cancer patients. CONCLUSION: These results indicate that endogenous BTG2 expression contributes to the migratory potential of bladder cancer cells. Moreover, high levels of BTG2 in bladder cancers are linked to decreased cancer-specific survival. These findings question the conception that BTG2 generally acts as a tumour suppressor and typically represents a favourable clinical marker for cancer patients.

Renal ischaemia/reperfusion injury: possible role of aquaporins.

Renal ischaemia/reperfusion (I/R) injury is a common problem that occurs when blood flow is interrupted to the kidney in case of kidney transplantation, aortic cross-clamping and shock with subsequent resuscitation. Renal I/R injury is a complex conditions which includes the onset of an inflammatory process, which is associated with impairment of concentrating ability of the kidney and impairment of solute transport. Characteristically, renal I/R injury is associated with marked reduction in the protein expression of renal aquaporins (AQPs) mainly (AQP1, AQP2 and AQP3), and solute transporters were observed in this condition and could account for the impaired urinary concentration that observed in this condition. Recently, many agents were tested for a possible protective effect against this insult such as erythropoietin (EPO), α-melanocyte-stimulating hormone (α-MSH) and α-lipoic acid which were proved to prevent downregulation of AQPs and solute transporters. The aim of this short review is to outline the potential pathophysiological role of AQPs in renal I/R injury and to put a spotlight on the modulation of renal functions impairment in renal ischaemia by new drugs that prevent downregulation of AQPs.

Extended radical lymphadenectomy in patients with urothelial bladder cancer: results of a prospective multicenter study.

PURPOSE: Previous studies demonstrate a positive correlation between postoperative survival and the extent of pelvic lymphadenectomies in patients with bladder cancer. However, the distribution of nodal metastases has not been examined in sufficient detail. Therefore, we conducted a comprehensive prospective analysis of lymph node metastases to obtain precise knowledge about the pattern of lymphatic tumor spread. MATERIALS AND METHODS: Between 1999 and 2002 we performed 290 radical cystectomies and extended lymphadenectomies. Cranial border of the lymphadenectomy was the level of the inferior mesenteric artery, lateral border was the genitofemoral nerve and caudal border was the pelvic floor. We made every effort to excise and examine microscopically all lymph nodes from 12 well-defined anatomical locations. RESULTS: Mean total number and standard deviation of lymph nodes removed was 43.1 +/- 16.1. Nodal metastases were present in 27.9% of patients. The percentage of metastases at different sites ranged from 14.1% (right obturator nodes) to 2.9% (right paracaval nodes above the aortic bifurcation). By studying cases of unilateral primary tumors or with only 1 metastasis we observed a preferred pattern of metastatic spread. However, there were many exceptions to the rule and we did not identify a well-defined sentinel lymph node. CONCLUSIONS: We strongly recommend extended radical lymphadenectomy to all patients undergoing radical cystectomy for bladder cancer to remove all metastatic tumor deposits completely. The operation can be conducted in routine clinical practice and our data may serve as a guideline for future standardization and quality control of the procedure.

Renal transplantation in children with abnormal lower urinary tract.

OBJECTIVE: This retrospective study reports the outcomes as well as pre- and posttransplant urologic treatments of renal transplantation for children with an abnormal lower urinary tract (LUT). METHODS: Between March 1981 and December 2001, 195 children (< or =18 years of age) received live-donor kidney transplants. The 15 recipients (14 boys and 1 girl, mean age 13.5 +/- 3 years) who had lower urinary tract disorders included posterior urethral valves (PUV) with valve bladder (n=12) and neuropathic bladders secondary to meningomyelocele (n=3). These children were evaluated by voiding cystourethrogram, cystourethroscopy, and cystometry. The children with PUV were maintained on clean intermittent catheterization (CIC) and a detrusor relaxant at least 3 months before transplantation. Augmentation ileocystoplasty or continent cutaneous diversion were used in three patients. The graft and patient survivals as well as complications in this cohort was compared with a group of children with normal LUT, who underwent renal transplantation during the same period. RESULTS: One child died in the early posttransplant period due to rupture of the external iliac artery. Follow-up ranged from 6 months to 16 years (mean=4.5 years). During the same period the graft and patient survival rates were comparable between the group of children with versus without abnormal LUT. Furthermore, mean serum creatinine and creatinine clearance values were also comparable. The group with an abnormal LUT showed a higher incidence of urinary fistula (3/14) and recurrent UTI and/or bacteremia (4/14). CONCLUSIONS: Renal transplantation is feasible with good results for children with abnormal LUT. Pre- and posttransplant urologic management is critical for a successful outcome. However these children display a high incidence of urologic and infectious complications.

Nerve-sparing robot-assisted radical cystoprostatectomy and urinary diversion.

OBJECTIVE: To develop a technique of nerve-sparing robot-assisted radical cystoprostatectomy (RRCP) for patients with bladder cancer. PATIENTS AND METHODS: Robotic assistance should enhance the ability to preserve the neurovascular bundles during laparoscopic radical cystectomy. Thus we undertook RRCP and urinary diversion using a three-step technique. First, using a six-port approach and the da Vinci Surgical System (Intuitive Surgical, Sunnyvale, CA, USA), one surgeon carried out a complete pelvic lymphadenectomy and cystoprostatectomy using a technique developed specifically for robotic surgery. The neurovascular bundles were easily identified and dissected away, the specimen entrapped in a bag and removed through a 5-6 cm suprapubic incision. Second, a different surgical team exteriorized the bowel through this incision and created a neobladder extracorporeally. Third, the neobladder was internalized, the incision closed and the primary surgeon completed the urethro-neovesical anastomosis with robotic assistance. RESULTS: RRCP was carried out in 14 men and three women by the primary surgeon (M.M.). The form of urinary reconstruction was ileal conduit in three, a W-pouch with a serosal-lined tunnel in 10, a double-chimney or a T-pouch with a serosal-lined tunnel in two each. The mean operative duration for robotic radical cystectomy, ileal conduit and orthotopic neobladder were 140, 120 and 168 min, respectively. The mean blood loss was < 150 mL. The number of lymph nodes removed was 4-27, with one patient having N1 disease. The margins of resection were free of tumour in all patients. CONCLUSIONS: We developed a technique for nerve-sparing RRCP using the da Vinci system which allows precise and rapid removal of the bladder with minimal blood loss. The bowel segment can be exteriorized and the most complex form of orthotopic bladder can be created through the incision used to deliver the cystectomy specimen. Performing this part of the operation extracorporeally reduced the operative duration.

Treatment of urethral defects: skin, buccal or bladder mucosa, tube or patch? An experimental study in dogs.

PURPOSE: We studied 3 graft materials and 2 urethroplasty techniques in 24 adult male mongrel dogs. MATERIALS AND METHODS: The animals were divided into 2 equal groups. In group 1 a 4 cm. segment of perineal urethra was excised and tubed urethroplasty was performed using free full-thickness skin, buccal and bladder mucosa grafts in 4 dogs each. In group 2 a 4 cm. urethral strip was excised and onlay urethroplasty was performed using the same graft materials in 4 dogs each. Retrograde urethrography was done and the animals were sacrificed at week 12. Autopsy specimens were calibrated with a 10Fr catheter. Hematoxylin and eosin stained sections were examined. Masson's trichrome stain was used to determine the extent of fibrosis. RESULTS: Urethral stricture was diagnosed by radiology and confirmed by calibration in 8 of the 12 dogs (66%) in group 1 but in only 1 of the 12 (8%) in group 2 (p <0.004). Buccal mucosa grafts were associated with the lowest stricture rate of 12%, followed by 37% for bladder mucosa and 62% for skin (p <0.2). There was no difference in neovascularization among the 3 grafts. Graft shrinkage was less than 10% for buccal mucosa compared with 20% to 40% for skin and bladder mucosa. The shrinkage rate was similar for the onlay and tube techniques. The intensity of chronic inflammation and fibrosis was highest in the skin grafts. Circumferential fibrosis was noted in association with tubed urethroplasty but not with the onlay technique. CONCLUSIONS: The theoretical advantages of buccal mucosal grafts were pathologically demonstrated. When possible, grafts should be used as an onlay rather than as a complete tube.

Prognostic significance of tumour angiogenesis in schistosoma-associated adenocarcinoma of the urinary bladder.

OBJECTIVE: To report on tumour angiogenesis and its relationship with morphological variables and prognosis in adenocarcinoma of the urinary bladder associated with schistosomiasis. PATIENTS AND METHODS: Fifty-five vesical adenocarcinomas were evaluated from 30 men and 25 women (mean age 47.2 years, sd 8.7, range 30-65) who were followed up after radical cystectomy and urinary diversion for a mean (sd, range) of 61 (43.5, 2.7-159.5) months. Vessels were stained immunohistochemically using an antibody to the platelet endothelial cell-adhesion molecule CD31. Microvessels were counted in active areas of angiogenesis within the tumours (at x250) and the microvessel density (MVD) quantified using the mean of three counts. Treatment failure was defined as death from cancer or the development of local recurrence or distant metastasis. Kaplan-Meier survival curves and Cox's proportional hazard model were used to assess survival. RESULTS: The overall 5- and 10-year survival rates were 57% and 51%, respectively. The presence of lymph node metastasis and high mean vascular density (> 26) were significantly associated with a poor prognosis. The 5-year survival for patients with negative lymph nodes was 66% while no patients with positive nodes survived for 5 years (P < 0.001); the survival was 72% for patients with a low MVD and 33% for those with a high MVD (P = 0.0016). From individual results plotted against vascularity in lymph node-negative patients, there was a significantly better outcome for those with a low MVD (< or = 26; P = 0.0099); this significance was maintained on multivariate analysis. However, there was no significant relationship between angiogenesis and the different clinicopathological factors apart from the grade (P = 0.03); tumour stage, grade and DNA profile had no significant effect on survival in these patients. CONCLUSIONS: These findings suggest that assessing angiogenesis using the MVD provides an independent predictor of survival in patients with adenocarcinoma of the urinary bladder.

Complications of orthotopic ileal W-neobladder with serous lined extramural tunnel in 520 patients

Objective: To report on the complications following orthotopic ileal W-neobladder with serous lined extramural antireflux ureteral implantation. Patients and Methods The records of 520 patients that had undergone one-stage radical cystectomy and orthotopic ileal neobladder were reviewed retrospectively including the follow-up files. Special attention was directed towards the mortality; morbidity and late complications recorded during the follow-up evaluation. Results Hospital mortality was reported in 5 cases. Eighty-one early complications were observed in 60 patients (11.5); including GIT complications in 13; wound infection in 22 and pouchovaginal fistulae in 3. Out of 520 patients 400 were evaluable (308 men and 92 women). Tumor recurrence was documented in 101 patients (20) including 5 with isolated urethral recurrence (0.9). Late complications included pouch stones in 13; outflow obstruction in 12; mucus retention in 4 and adhesive bowel obstruction in 5. Urinary incontinence was found in 9and 18of patients during the day and night times; respectively. Hypercontinence was documented in 9 females. Upper tract deterioration was observed in 36 out of 785 renal units (4.5) due to anastomotic stricture in 32 and chronic pyelonephritis in 4. Poucho-ureteral reflux was seen in 28 units (3.6). Bacteria were isolated in the urine of 32 of 316 examined patients. Serum creatinine was normal in all but 4 patients and 44 patients (11) suffered from subclinical chemical metabolic acidosis. Conclusion The incidence of complications following ileal W-neobladder is low and amenable to treatment in most of the patients. Furthermore; the technique has proved its efficacy and durability

Prostatic adenocarcinnoma in cysprostatectomy specimens remolved for bladder tumors in bilharzial patients

Objective To determine the incidence of prostatic adenocarcinoma in bilharzial patients who previously underwent radical cystoprostatectomy for bladder tumors. Patients and Methods From February 1997 to February 1999; 249 male patients with bladder cancer were screened for prostate cancer prior to cystectomy using DRE and total PSA assay; as well as transrectal ultrasound-guided prostatic biopsies. Then the cystoprostatectomy specimens were serially sectioned (every 3 mm) and histologically examined. Results Prostatic adenocarcinoma was detected by ultrasound-guided prostatic needle biopsies in 2 cases; while in 18 it was discovered incidentally after cystoprostatectomy (total 20 patients = 8). Gleason score was 6 in 16 patients; 7 in 3 patients and 8 in the remaining patient. Perineural lymphatic permeation was observed in 4 cases and extracapsular extension in one. Conclusion Compared to previous reports on non-bilharzial patients; the incidence of prostate cancer in the cystoprostatectomy specimens of bilharzial patients was low; and the tumors were clinically insignificant in most of the cases

Functional results of orthotopic ileal neobladder with serous-lined extramural ureteral reimplantation: experience with 450 patients.

PURPOSE: We report functional results of the orthotopic ileal neobladder using a serous-lined extramural tunnel as an antireflux procedure. MATERIAL AND METHODS: One-stage radical cystectomy and orthotopic ileal W-shaped neobladder creation were performed in 353 male and 97 female patients for invasive bladder cancer. The ureters were reimplanted using a serous-lined extramural tunnel for reflux prevention. Of the patients 344 were evaluable at a mean followup plus or minus standard deviation of 38 +/- 25 months. Evaluation included clinical and radiographic studies to determine functional and oncological outcomes. RESULTS: Four patients (0.8%) died in the hospital. Early complications in 42 patients (9%) were treated conservatively but 3 women underwent vaginal repair of a pouch-vaginal fistula. During the observation period there were 90 oncological failures, of which 3 were isolated urethral recurrence. Late complications included pouch stones in 10 cases, outflow obstruction in 11, mucous retention in 2, adhesive bowel obstruction in 3 and hypercontinence in 9 females. The incidence of daytime and nighttime continence was 93.3% and 80%, respectively. The upper tracts remain unchanged or improved in 96.2% of the reimplanted renal units, while reflux was observed in 3%. CONCLUSIONS: The serous-lined extramural tunnel has proved its efficiency and durability as an antireflux technique.

Long-term outcome analysis of low pressure rectal reservoirs in 33 children with bladder exstrophy.

PURPOSE: The augmented valved rectum and double folded rectosigmoid bladder represent 2 modifications of ureterosigmoidostomy. Both procedures improve continence by lowering the reservoir pressure. We present the outcome of these techniques on the upper urinary tract, continence, metabolic profile, linear growth and bone density. MATERIALS AND METHODS: Between March 1987 and May 1997, 22 boys and 11 girls with bladder exstrophy underwent urinary diversion to a low pressure rectal reservoir. Patient age at surgery ranged from 2 to 13 years (mean 5.4). The augmented valved rectum technique was used in 18 cases and the double folded rectosigmoid bladder method was used in 15. Serial followup ultrasounds were obtained and voiding proctography was performed 1 year postoperatively in all patients. Supine height was measured at last followup in all cases. Serum electrolytes, arterial blood gases, the results of which were plotted on an acid base nomogram, and bone density using dual energy x-ray absorptiometry were measured in all patients. Prophylactic alkalization was administered to all patients. RESULTS: Mean followup is 66 months (range 24 to 148). All patients are continent during the daytime with an emptying frequency of 3 to 5 times, and all are continent at night. No patient experienced pyelonephritis or clinical acidosis. The upper urinary tract was either improved or stabilized in 64 of 66 renal units. No patient had reflux to the upper urinary tract. All patients had normal serum creatinine, sodium, potassium, calcium and phosphorus. Hyperchloremia was noted in 19 of the 33 patients (57%), and arterial blood gases showed subclinical metabolic acidosis in 18 (55%). Supine height measurements at last followup revealed that 19 of the 33 patients (57%) had decreased linear growth (below 3rd percentile). All patients had significant reduction in bone density, and mean for age corrected bone density was 70% (standard deviation 10.9%). Both groups (augmented valved rectum and double folded rectosigmoid bladder) were comparable in regard to age, sex and followup duration. There was no statistically significant difference between the groups in any parameter measured. CONCLUSIONS: The augmented valved rectum and double folded rectosigmoid bladder provide preservation of the upper urinary tract with excellent continence rates. However, prophylactic alkalization and functional isolation of the reservoir do not prevent the long-term metabolic consequences. Subclinical metabolic acidosis and decreased linear growth are to be anticipated in more than 50% of patients. Moreover, significant bone demineralization is to be expected in all of these patients.

Comparison of genetic changes in schistosome-related transitional and squamous bladder cancers using comparative genomic hybridization.

The development of bladder tumors has been associated with a number of causative agents, including schistosomiasis. Schistosome-related cancers show different clinical and pathological features compared with non-schistosome-related bladder cancers, occurring in younger patients, and being predominantly of squamous cell type. This study addresses the difference between squamous and transitional tumor types in the presence of schistosome infection as a measure of the relationship between tumor genotype and phenotype. We have used comparative genomic hybridization to analyze primary muscleinvasive schistosome-related bladder tumors in 54 patients. Twenty-six of these tumors were squamous cell carcinomas; the remaining 28 were of transitional cell type. On average, transitional cell tumors showed 1.8 times the number of chromosomal aberrations as squamous cell tumors (14.4 versus 8.2, P: < 0.001). For both groups combined, the most prevalent genetic alterations were losses of 8p and 18q, and gains of 8q. Transitional cell cancers also showed frequent losses involving 5q, 9p, 10q, 11p and 11q, and gains at 1q and 17q. Loss of 11p was significantly more frequent in TCC than in SCC tumors (50 versus 4%, P: = 0.01). Squamous cell cancers showed more frequent losses of 17p and 18p than transitional tumors, which was clearly significant given the overall reduced frequency of changes in squamous cancers (P: = 0.001 and P: = 0.03, respectively). These data show that different histologic subgroups of bladder tumors are characterized by distinct patterns of chromosomal alterations. The genetic changes found in the transitional cell group are similar to those reported in non-schistosome-related transitional cell tumors, but differ from tumors exhibiting squamous differentiation.

A case of ileal ureter with proximal antireflux system.

BACKGROUND: The initial experience of constructing a new antirefluxing valve at the uretero-ileal junction with ileal substitution is reported. METHODS: A new antirefluxing valve was constructed at the uretero-ileal junction with ileal substitution by fixing the distal part of the ureter between the psoas muscle and ileal segment (the ileo-psoas tunnel technique). DISCUSSION: The valve created by the technique has been working effectively for preventing the ileo-ureteral reflux. Pre-operative hydronephrosis was improved and the renal function has been well preserved. CONCLUSION: The ileo-psoas tunnel technique is worthwhile when ileal substitution of the ureter is indicated.

Serous lined extramural ileal valve: a new continent urinary outlet.

PURPOSE: We report the functional results following the use of serous lined extramural valve as an antireflux technique and urinary outlet for continent urinary diversion. MATERIALS AND METHODS: The procedure was performed in 18 men and 5 women. The technique entails fashioning 2 serous lined extramural troughs in a detubularized W-shape ileal reservoir. A tapered ileal segment is embedded in 1 trough as an antireflux valve and the ureters are anastomosed to its proximal end. Another tapered ileal segment or the appendix is embedded in the second trough and acts as a continent cutaneous outlet. RESULTS: No operative or postoperative mortality was observed. One patient had prolonged ileus which was treated conservatively. All patients were evaluable with a mean followup of 19 months. All patients but 1 were continent day and night. No catheterization difficulties were reported. Evacuation intervals were 4 to 5 hours. Radiographic evaluation demonstrated a continent compliant reservoir, stable and straight outlet, and absence of pouch and ureteral reflux. CONCLUSIONS: This procedure is technically feasible, surgically versatile, applicable for urinary diversion or conversion and associated with satisfactory outcome.

Primary adenocarcinoma of the urinary bladder: a report of 185 cases.

OBJECTIVE: To evaluate the outcome after the treatment of primary non-urachal vesical adenocarcinoma and to determine the significant prognostic factors. PATIENTS AND METHODS: The records of 185 patients with vesical adenocarcinoma were reviewed. The pathological evaluation included the determination of pathological stage, tumour grade, presence or absence of mucin and its location, evidence of bilharzial infestation and flow-cytometric DNA analysis. The mean follow-up of the treated patients was 3.1 years. Disease-free survival was estimated and the results correlated with patient and tumour characteristics (univariate analysis). Cox's proportional hazards analysis was used to determine prognostic factors. RESULTS: The overall 5-year disease-free survival was 55%; only three factors had a significant impact on survival, the tumour pathological stage and grade, and lymph node involvement. CONCLUSIONS: Radical cystectomy remains the only satisfactory treatment option for primary vesical adenocarcinoma. Tumour stage, grade and lymph node involvement are the only significant prognostic factors.

Double folded rectosigmoid bladder with a new ureterocolic antireflux technique.

PURPOSE: We present a new method of urinary diversion to the rectum. MATERIALS AND METHODS: Between 1992 and 1995 a new surgical procedure was used in 32 women, 20 men and 12 children 3 to 60 years old (mean age plus or minus standard deviation 35.4 +/- 2.2). The main indication for diversion was invasive bladder carcinoma. Surgery entailed creation of an S-shaped double folded rectosigmoid reservoir with implantation of the ureters via an extramural serous lined antireflux technique. RESULTS: One patient died of a massive pulmonary embolism postoperatively. Followup ranged from 6 to 36 months (mean 19.2 +/- 7.0). During the observation period 6 patients died of local recurrence and/or distant metastasis within 8 months. Of the patients 57 are currently evaluable. All patients are continent during the day with an emptying frequency of 2 to 4 times. Nocturnal enuresis was observed in 4 children who responded favorably to imipramine hydrochloride therapy. Upper urinary tract function was maintained or improved in 95% of the patients. No clinical evidence of acidosis was observed, since all patients were kept on prophylactic oral alkalization. CONCLUSIONS: The procedure can circumvent some of the inherent disadvantages of ureterosigmoidostomy and is a good alternative to orthotopic bladder substitution when the urethra cannot be used.

Chloride absorption in patients with a continent ileocaecal reservoir (Mainz pouch I).

OBJECTIVE: To determine the rate of radioactive chloride absorption at various times after surgery in patients with a continent ileocaecal reservoir (Mainz pouch I). PATIENTS AND METHODS: The study was conducted on 20 patients (15 males and five females, mean age 47 years, range 15-72) who had undergone a Mainz pouch I urinary diversion. The patients were divided into three groups according to the duration of the post-operative follow-up, i.e. group 1 for < 6 months (n = 7), group 2 for 6-12 months (n = 8) and group 3 for > 12 months (n = 5). Radioactive 38Cl (20 MBq) was instilled into the pouch and the radioactivity determined in the blood, pouch and body interstitium every 20 min for 3 h. Samples for arterial blood-gas and acid-base profiles were obtained before and after instillation. RESULTS: In patients in group 1, 93% of the instilled chloride was absorbed into the circulation, while 51% was absorbed by patients in group 3. The acid-base profile showed no significant changes before and after chloride instillation. CONCLUSION: The absorption of chloride declines markedly with time after surgery in patients with a Mainz pouch I ileocaecal reservoir.

Urinary diversion in children and young adults using the Mainz Pouch I technique.

OBJECTIVES: To determine the late complications and consequences for renal function, vitamin and acid-base metabolism after application of the Mainz Pouch I (MZP-I) technique in children and young adults. PATIENTS AND METHODS: To November 1994, the MZP-I procedure was carried out in 463 patients at our institution, 91 of whom were children and adolescents (< or = 20 years old) using bladder augmentation in 21 and a continent cutaneous stoma in 70. A minimum follow-up of 1 year was possible in 87 patients or 163 renal units (RUs) with a mean of 5.5 years (range 1-10.5). RESULTS: At the last examination, 23 of 55 (42%) preoperatively dilated RUs had improved. 131 of the 163 RUs (80%) were stable and nine RUs (5.5%) showed a slight clinical asymptomatic increase in the upper tract dilatation. Through an extraperitoneal flank incision, 11% of the RUs which developed stenosis at the ureterocolic anastomosis were successfully reimplanted (16% in patients with neurogenic disorders, 17% with pre-operative irradiation and 5% in the remaining patients). Two of 32 patients with an intussuscepted and invaginated ileal nipple required re-operation due to incontinence, but none of the patients with an appendiceal stoma were incontinent. Open revision of a stomal stenosis was performed in three and endoscopic treatment in nine patients. In 54 patients, the levels of vitamins A, B1, B2, B6, E, folic and bile acid were within normal ranges. There was no significant decrease in vitamin B12 levels after operation. In none of the patients with normal pre-operative creatinine values had the levels increased and none developed severe acidosis or bowel neoplasm. CONCLUSION: The MZP-I is recommended as a technique for bladder augmentation or continent urinary diversion in children and young adults, with an acceptable complication rate which offers long-term protection of the upper urinary tract.