ULTRASTRUCTURE OF THE BLADDER IN CLASSIC EXSTROPHY: CORRELATION WITH DEVELOPMENT OF CONTINENCE

Intraoperative laser angiography in bladder exstrophy closure: A simple technique to monitor penile perfusion

BACKGROUND

The successful repair of Bladder Exstrophy remains one of the biggest challenges in Pediatric Urology. The primary focus has long been on the achievement of urinary continence. Historically there has been less focus on early penile outcomes. To this end we have incorporated penile perfusion testing using intraoperative laser angiography in to our operative approach.

OBJECTIVE

We hypothesize that assessment of penile perfusion at various points in the procedure is a feasible technique that may assist in decision making during the repair of this complex condition. This will reduce the risk of tissue compression and potential loss of penile tissue that has been reported to occur as a complication of the procedure.

STUDY DESIGN

Consecutive patients presenting with bladder exstrophy were evaluated at four stages of their operation (i.e. following induction of anesthesia, after bladder mobilization, following internal rotation of the pubis and at the end of the procedure) by infusing indocyanine green (ICG) at a dose of 1 mg per 10 kg body weight. Measurements were taken at 80 s post infusion and the medial thigh served as the reference control. Postoperative penile viability was evaluated by visual inspection and palpation three months following the procedure.

RESULTS

Eight consecutive patients were included in this study. Perfusion was easy to measure and posed no significant technical difficulties. Penile perfusion increased slightly following bladder dissection. Internal rotation of the hips with apposition of the symphysis pubis resulted in an average 50% reduction in penile blood flow. Patients undergoing CPRE experienced an additional mean 33% drop in blood flow. In all eight cases the penis was symmetric and healthy with no sign of tissue loss at three months follow up.

CONCLUSIONS

This pilot study demonstrates that the measurement of penile perfusion utilizing intraoperative laser angiography is easy to employ and should be considered a reasonable adjunct to tissue assessment in this complex condition. Marked reduction in penile blood flow may occur without any outward clinical signs. Penile perfusion is markedly reduced by apposition of the symphysis pubis and, in the immediate postoperative period, there may be further reduction in penile blood flow with CPRE as opposed to a staged repair. Future correlation with measures of penile viability and function are needed to define the clinical utility of this modality.

Delaying reclosure of bladder exstrophy leads to gradual decline in bladder capacity

INTRODUCTION

After unsuccessful repair of bladder exstrophy, when to repeat surgical intervention is unclear. One must balance time required for tissue healing with the damaging effects of an exposed urothelium to the environment.

OBJECTIVE

The authors aim to study whether a relationship exists between bladder growth/capacity and time till eventual successful closure.

STUDY DESIGN

An institutional database of exstrophy-epispadias complex patients was queried for failed exstrophy closure with successful repeat reconstruction, at least three consecutive bladder capacity measurements, and measurements obtained at least three months following successful closure. Patients closed successfully in the neonatal period were used as a comparative group. Linear mixed effects models were used to study the effect of time and age on bladder capacity.

RESULTS

Forty-seven patients requiring reclosure and 117 who had successful neonatal closures were included. Two models were created. The first linear mixed effects model found that for a given age, the bladder capacity declined approximately 9.6 mL per year (p = 0.016). The second model found that when time to successful closure was grouped by quartiles, compared to neonates, those in the fourth quartile had significantly decreased bladder capacity of 28.8 cc (p = 0.042). An interaction model comparing neonates and those requiring reclosure did not demonstrate a significant change in bladder growth rate (p = 0.098). A model stratified by quartiles similarly did not find any significant impact to bladder growth rate.

DISCUSSION

From the general linear mixed effects models, the authors conclude when compared to neonates, (1) there was an approximate 9.6 cc loss of total bladder capacity per year taken until successful closure, and that (2) those who were delayed the longest had the most significant difference in bladder capacity. This study required stricter inclusion criteria compared to previous publications, and therefore the conclusions that can be drawn regarding bladder growth rates may be more reliable. Future studies will examine the effects of delayed closure on the bladder at the cellular level.

CONCLUSIONS

There is a demonstrable significant impact on overall bladder capacity with increasing delay to successful reclosure. One should be cautious when prolonging reconstruction of the bladder as these data demonstrate a time dependent decline in overall capacity.

Spontaneous bladder rupture in non-augmented bladder exstrophy

OBJECTIVE

Bladder perforation is not commonly described in bladder exstrophy patients without bladder augmentation. The goal of this study was to identify the risk factors of spontaneous perforation in non-augmented exstrophy bladders.

METHODS

The study was a retrospective multi-institutional review of bladder perforation in seven male and two female patients with classic bladder exstrophy-epispadias (E-E).

RESULTS

Correction of E-E was performed using Kelly repair in two and staged repair in seven (Table). Bladder neck repair was performed in eight patients at a mean age of 6 years. Three patients had additional urethral surgery. Before rupture, six patients were voiding only per urethra. Two patients were voiding urethrally but were also performing occasional CIC via a Mitrofanoff. One patient was performing CIC 3 hourly per urethra. Six were dry during the day. Six of the patients had lower urinary tract symptoms: five had frequency and four were straining to void. Two had suffered episodes of urinary retention. Pre-rupture ultrasound showed that the upper urinary tract was dilated in four patients. Micturating cystourethrogram was performed in six showing vesico-ureteral reflux in five. Two had urethral stenosis. Nuclear medicine was done in three patients with two abnormal differential function. Urodynamics was performed in two patients with low capacity (100 mL) and hypocompliant (<10) bladders. Both had high leak point pressures: 60 cmH₂O at 100 mL. The mean age at rupture was 11 years, with a range of 5-20 years. Patients presented with abdominal pain, associated with signs of intestinal obstruction in seven and fever in two. Eight patients underwent laparotomy and one prolonged drainage via SPC. Simple closure was performed in seven and bladder neck closure in one, because of extension of the rupture inferiorly. All patients recovered well. Following rupture, five underwent augmentation and Mitrofanoff. One of these suffered a recurrent rupture. Two other patients refused augmentation and Mitrofanoff and one of these has since had a subsequent rupture.

CONCLUSIONS

The limitations of this series include the small number of patients and its retrospective nature, without knowledge of the incidence. Bladder rupture is a risk even in non-augmented bladder exstrophy. It is potentially life-threatening and most often requires laparotomy. Rupture occurs because of poor bladder emptying and/or high pressure. Urodynamics may identify those at risk. CIC with or without augmentation should not be delayed once poor bladder emptying and/or high pressure are identified.

Comparing the bulking effect of calcium hydroxyapatite and Deflux injection into the bladder neck for improvement of urinary incontinence in bladder exstrophy-epispadias complex

OBJECTIVES

The aim of this study was to evaluate the efficacy of the endoscopic injection of calcium hydroxyapatite (CaHA) into the bladder neck (BN) region of patients with urinary incontinence and bladder exstrophy-epispadias complex (BEEC).

PATIENTS AND METHODS

We designed a retrospective cohort study in which we retrospectively studied medical charts of female and male patients of BEEC who had undergone CaHA or Deflux injection for continence improvement between 2009 and 2014. Sixteen incontinent patients with a mean ± SD age of 8.09 ± 3.5 years received an endoscopic submucosal injection of 5.4 ml of pure CaHA powder with autologous plasma (group A). Patients in group B (N = 21), control group, with a mean ± SD age of 7.51 ± 2.8 years received Deflux injection (5.1 ml). The mean follow-up after injection was 38 ± 5.2 and 33 ± 4.1 months in groups A and B, respectively.

RESULTS

No post-injection complication was detected in none of the patients during the follow-up. Eleven patients (68.75%) in group A became socially dry following 1-2 injections, the degree of incontinence was improved in 4 patients (25%), and there was no change in one patient (6.25%). However, Deflux injection resulted in complete dryness in 14 (66.66%), improvement in the degree of incontinence in 5 (23.81%) and no change in 2 patients (9.52%), leading to no significant difference in continence achievement between CaHA and Deflux groups (p = 0.9). The statistical analysis was not significantly different in terms of bladder capacity (p = 0.7) or Q max (p = 0.8).

CONCLUSION

The preliminary results of this study revealed that CaHA may be applied as an affordable bulking agent in treatment of urinary incontinence in BEEC.

Sub-urothelial polyp enucleation resection and urothelial auto-augmentation cystoplasty: a simple method for bladder exstrophy-epispadias complex reconstruction in bladder plate polyposis

OBJECTIVES

To report the results of a novel technique of sub-urothelial polyp enucleation resection (SUPER) and urothelial auto-augmentation cystoplasty (UAAC) in patients with bladder exstrophy and polyposis plate.

METHODS

Twenty-eight patients with bladder exstrophy covered by plate polyposis were referred for further management. From these, 12 patients had undergone SUPER, UAAC technique, and subsequent bladder closure. In this technique, the urothelium covering the polyps was utilized as tissue for auto-augmentation cystoplasty. Sixteen patients had been operated by simple polyps' excision and bladder closure. Biopsies of polyps were obtained in both groups at the time of closure for pathological evaluations. The bladder plate was measured pre-and post-bladder plate augmentation. The patients were evaluated every 3 months for 1 year and biannually thereafter for urinary continence and social dryness. Dry period of >3 h during the day with or without nocturnal incontinence was defined as social dryness.

RESULTS

All patients experienced an uneventful postoperative period. No sign of metaplasia or dysplasia was observed in the histological and cystoscopy evaluations. These findings suggest that neither polyp recurrence nor bladder tumor development has occurred in any of the groups. The urinary continence improved significantly in the polyp's urothelial coverage augmentation cystoplasty technique (66.7%), while 31.3% of patients in simple closure technique achieved continence. Significantly higher mean bladder capacity was obtained in the augmentation group (190 ± 38 ml) and (119 ± 21 ml), respectively. Postoperative mild hydronephrosis and vesicoureteral reflux were significantly lower in auto-augmentation technique.

CONCLUSION

The final clinical outcome of children with bladder exstrophy polyposis is promising. The combined SUPER and UAAC technique is feasible, safe and reproducible option for bladder exstrophy-epispadias complex (BEEC) patients with bladder plate polyposis. However, it will add one supplementary operation to the single or staged bladder reconstruction. These patients may warrant further surveillance with histopathological evaluations during the adult life.

New advances in the pathophysiologic and radiologic basis of the exstrophy spectrum

The exstrophy-epispadias complex is a rare spectrum of anomalies affecting the genitourinary system, anterior abdominal wall, and pelvis. Recent advances in the repair of classic bladder exstrophy (CBE) and cloacal exstrophy (CE) have resulted in significant changes in outcomes of surgical management (including higher continence rate, fewer surgical complications, and better cosmesis) and health-related quality of life in these patients. These noteworthy changes resulted from advances in the pathophysiological and genetic backgrounds of this disease and better radiologic assessment of the three-dimensional anatomy of the bony pelvis and its musculature. A PubMed search was performed with the keyword exstrophy. The resulting literature pertaining to genetics, stem cells, imaging, tissue engineering, epidemiology, and endocrinology was reviewed. The following represents an overview of the advances in basic science understanding and imaging of the exstrophy-epispadias spectrum and discusses their possible and future effects on the management of CBE and CE.

Expression and potential clinical significance of urothelial cytodifferentiation markers in the exstrophic bladder

PURPOSE

We characterize the urothelium from patients with classic bladder exstrophy-epispadias complex for the expression of proteins associated with urothelial differentiation, and discuss a potential impact of urothelial phenotype on the structural and functional properties of the bladder template following bladder closure.

MATERIALS AND METHODS

From 2005 to 2010 bladder biopsies from 32 infants with bladder exstrophy-epispadias complex obtained at primary bladder closure were collected. After histological assessment immunochemistry was used to investigate the expression of uroplakin IIIa, cytokeratin differentiation restricted antigens CK13 and CK20, and tight junction protein claudin 4.

RESULTS

Overall tissue morphology showed gross alterations with inflammatory, proliferative and metaplastic changes in most specimens. Sections of intact epithelium were present in 78% of biopsies. With respect to urothelial phenotype, CK13 was expressed in all specimens, whereas UPIIIa and CK20 were absent in 76% of the tissues examined. Of the biopsies 52% revealed an irregular expression pattern of tight junction protein Cl-4.

CONCLUSIONS

This is the first study to our knowledge to characterize the urothelium from infants with bladder exstrophy-epispadias complex for the expression of urothelial differentiation associated antigens. Our findings suggest urothelial differentiation changes in a majority of exstrophic bladders, at least at primary bladder closure. Although the underlying etiology remains to be established, abnormal urothelial differentiation may result in a dysfunctional urothelial barrier with implications for the structural and functional properties of the bladder template. Despite the study limitations, our preliminary findings provide a platform for further investigation of the significance of the urothelium for the exstrophic bladder.

Delayed complete repair of exstrophy with testosterone treatment: an alternative to avoid glans complications?

PURPOSE

Since 1999, complete primary repair of exstrophy has represented a valid alternative in the treatment of exstrophy patients, offering one- stage reconstruction for all components of this malformation in newborns. The vast majority of cases are currently approached within 48/72 h of life, and risk of vascular injury to penile glans and/or corpora has been reported with increased frequency with this procedure. We report our initial experience with a delayed approach to complete repair, with bladder plate left intact and taken care at home by the parents, while awaiting for the patient to reach adequate weight. Delayed approach also enabled us to preoperatively stimulate phallic size with testosterone, a treatment which was so far confined only to redo or failed cases.

METHODS

Six male exstrophy patients were treated over a three-year (2007-2009) period. After initial workup, newborns were discharged home with bladder plate taken care by the parents. A weight of 4,500 g was arbitrarily deemed satisfactory for surgery. While at home, patients underwent preoperative testosterone stimulation (testosterone enanthate, four biweekly administrations of 100 mg/per square meter body surface). In each case biopsies of bladder mucosa were taken at time of surgery. Complications, age at surgery, increases in phallic size were extracted from clinical and surgical case notes.

RESULTS

Weight at surgery ranged from 4,510 to 5,600 g. Age range was 43-91 days. Mean increase in phallic size after testosterone stimulation was 8.3 mm. Three complications were observed: two were suprapubic fistulas, of these, one closed spontaneously and one required surgery subsequently. In one fascial dehiscence emergency closure was needed. Hypospadias occurred in all patients. All histologic specimens demonstrated a mildly inflamed bladder mucosa.

CONCLUSIONS

Delayed repair of bladder exstrophy allows to approach patients who have reached adequate weight and stabilization; if adequately cared for bladder plate shows minimal inflammation at surgery and can be managed by the parents at home. Deferring surgery also offers the advantages of preoperative testosterone stimulation, promotion of mother-baby relationship as well as of transfer to Centers with adequate experience and proficiency in all aspects of bladder exstrophy reconstruction.

Impact of epispadias repair on bladder growth in boys with classic bladder exstrophy

OBJECTIVE

Growth of the bladder in children with bladder exstrophy is primarily responsible for later ability to void continently. Improvement in bladder capacity has been noted in some boys following epispadias repair. Does the timing of epispadias repair influence the ability of the bladder to grow?

METHODS

Data were collected regarding bladder volume measurements, obtained under anesthesia using a standard technique, during yearly follow-up of boys with classic bladder exstrophy. Volume prior to epispadias repair was compared to the next volume measure following repair. Timing of epispadias repair was compared to changes in bladder capacity in 30 boys. Monthly increases in bladder capacity were calculated in boys repaired at <12 (4), 13-24 (12) and 25-48 (14) months.

RESULTS

Patients who had surgery prior to 12 months of age had the highest rate of monthly increase in bladder capacity (2.40 cc/month). Monthly growth rates were 1.91 cc/month for patients repaired at 13-24 months and 1.18 cc/month for those repaired at 25-48 months.

CONCLUSIONS

Epispadias repair does lead to early increase in bladder capacity in boys with classic bladder exstrophy. The monthly increases in bladder capacity are greater in boys <12 months. Improvement in bladder volume is less likely when epispadias is repaired after age 29 months.

The exstrophy-epispadias complex

Exstrophy-epispadias complex (EEC) represents a spectrum of genitourinary malformations ranging in severity from epispadias (E) to classical bladder exstrophy (CEB) and exstrophy of the cloaca (EC). Depending on severity, EEC may involve the urinary system, musculoskeletal system, pelvis, pelvic floor, abdominal wall, genitalia, and sometimes the spine and anus. Prevalence at birth for the whole spectrum is reported at 1/10,000, ranging from 1/30,000 for CEB to 1/200,000 for EC, with an overall greater proportion of affected males. EEC is characterized by a visible defect of the lower abdominal wall, either with an evaginated bladder plate (CEB), or with an open urethral plate in males or a cleft in females (E). In CE, two exstrophied hemibladders, as well as omphalocele, an imperforate anus and spinal defects, can be seen after birth. EEC results from mechanical disruption or enlargement of the cloacal membrane; the timing of the rupture determines the severity of the malformation. The underlying cause remains unknown: both genetic and environmental factors are likely to play a role in the etiology of EEC. Diagnosis at birth is made on the basis of the clinical presentation but EEC may be detected prenatally by ultrasound from repeated non-visualization of a normally filled fetal bladder. Counseling should be provided to parents but, due to a favorable outcome, termination of the pregnancy is no longer recommended. Management is primarily surgical, with the main aims of obtaining secure abdominal wall closure, achieving urinary continence with preservation of renal function, and, finally, adequate cosmetic and functional genital reconstruction. Several methods for bladder reconstruction with creation of an outlet resistance during the newborn period are favored worldwide. Removal of the bladder template with complete urinary diversion to a rectal reservoir can be an alternative. After reconstructive surgery of the bladder, continence rates of about 80% are expected during childhood. Additional surgery might be needed to optimize bladder storage and emptying function. In cases of final reconstruction failure, urinary diversion should be undertaken. In puberty, genital and reproductive function are important issues. Psychosocial and psychosexual outcome depend on long-term multidisciplinary care to facilitate an adequate quality of life.

Effects of steroid hormones on morphology and vascular endothelial growth factor expression in female bladder

OBJECTIVES

To investigate the roles of steroid hormones, including estrogen, progesterone, and testosterone, in the morphology and vascularization of the female bladder.

METHODS

A total of 70 adult, female Sprague-Dawley rats were divided into 7 groups: group 1, sham; group 2, ovariectomized rats without treatment; group 3, low-dose estradiol; group 4, high-dose estradiol; group 5, progesterone; group 6, estradiol combined with progesterone; and group 7, testosterone. All were given for 4 weeks. The serum steroid hormone levels were determined by radioimmunoassay. The total weight and thickness of the bladder were measured. Morphologic changes were observed under light and electron microscopy. The expression of vascular endothelial growth factor (VEGF) in the bladder was evaluated by immmohistochemistry and Western blotting.

RESULTS

The ovariectomized rats had a thinner bladder wall compared with the sham group (0.97 +/- 0.11 mm vs 1.10 +/- 0.10 mm, P < .05) and widened spaces between the detrusor muscle fascicles with collagen deposit. Estrogen reversed these changes, and testosterone increased the thickness of the bladder wall to 1.26 +/- 0.12 mm (P < .05). VEGF staining was mainly located in the urothelium and endothelial cells, with weak staining in the smooth muscles. VEGF was almost absent in the urothelium after ovariectomy. In the estrogen- and androgen-treated groups, although the expression of VEGF was significantly greater than that in the nontreated ovariectomized group, it was still lower than normal.

CONCLUSIONS

Our findings suggest the importance of steroid hormones in maintaining the integrity of the bladder structure and regulating the expression of VEGF in the female urinary tract. Both estrogen and androgen can reverse the bladder muscle atrophy induced by ovariectomy. However, the decline in VEGF expression in the bladder cannot be fully recovered with either estrogen or androgen replacement.

Standing the test of time: long-term outcome of reconstruction of the exstrophy bladder

The surgical management of classic bladder exstrophy has evolved over time. Different techniques are used to address the challenge of reconstructing these patients. We review the long-term outcomes of bladder exstrophy treatment from the published literature with regard to urinary continence, voiding and secondary complications. Continence now can be achieved in up to 80% of children in specialist centres. Whether such success can sustained into adult life is uncertain. About 40% of adults are dry in the best hands. Up to 84% of children can void, but there is some evidence that this function is lost with time in 70%. The need for bladder augmentation is widely variable between series, reported in 0-70% of children. This reduces the ability to void spontaneously to about 50% of children. It brings with it the later risk of metabolic disturbance and stone formation. Adults with exstrophy have a 694-fold increase in the risk of bladder cancer by the age of 40 years.

Surgery Insight: advantages and pitfalls of surgical techniques for the correction of bladder exstrophy

Staged reconstruction repair of bladder exstrophy results in hydronephrosis or renal scarring in 15-25% of patients. A cosmetically acceptable and functional phallus can be achieved in 85% of patients, 20-30% of whom will require more than one operation for penile reconstruction. Episodes of penile glans loss or corporal loss are rarely reported with this technique. Widely disparate results relating to complete urinary continence and volitional voiding have been published, with urinary continence reported to occur in 7-85% of patients. The need for bladder augmentation to obtain urinary continence also varies, with reports that somewhere between 10% and 90% of patients require an augmentation procedure to gain urinary continence. Complete primary repair of bladder exstrophy using the penile disassembly technique results in hydronephrosis or renal scarring in 0-30% of patients, and hypospadias, as a consequence of this repair, will occur in 30-70% of patients. Loss of the glans and corpora appear more frequently with penile disassembly than in staged reconstruction of bladder exstrophy, however, the exact incidence of this complication is unknown. Reported complete urinary continence and volitional voiding rates are also varied following penile disassembly, ranging from 25-65%. A modified bladder-neck reconstruction to gain urinary continence is reportedly required in 15-90% of patients, with 5-10% requiring both bladder augmentation and bladder-neck reconstruction. Experience with complete primary repair of bladder exstrophy, using the penile disassembly approach, seems promising but is not a panacea. To outline the risks and benefits regarding the various surgical techniques for bladder exstrophy, we would recommend the establishment of a national registry for patients with this disorder.