An initial report of a novel multi-institutional bladder exstrophy consortium: a collaboration focused on primary surgery and subsequent care

PURPOSE

For bladder exstrophy repair it is universally accepted that successful initial surgery is paramount to achieve the optimal outcome. Gaining the necessary surgical experience is challenging due to the rarity of bladder exstrophy. We report preliminary findings of a multi-institutional collaboration created to increase experience and proficiency with the care of bladder exstrophy.

MATERIALS AND METHODS

Our 3 institutions alternatively served as the host site for scheduled surgeries with observation, commentary and critique by visitors from the other sites. The technique was complete primary repair with bilateral iliac osteotomy. The timing of complete primary repair at age 1 to 3 months facilitated collaboration. We recorded patient demographics and outcomes, and the impact of this collaboration on our technique and experience. Video recording was used for real-time observation and teaching, and future analysis, editing and review.

RESULTS

A total of 16 site visits occurred from February 2013 through May 2014. Complete primary repair was performed in 9 males and 7 females with bladder exstrophy. Median age at complete primary repair was 2 months (range 0.1 to 28.8). Median followup was 8.9 months (range 2.8 to 18.2). All closures were successful with no dehiscence. Complications included urethrocutaneous fistula in 2 patients, 1 episode of pyelonephritis in 3 each and urethral obstruction in 2 females, of whom 1 required clean intermittent catheterization.

CONCLUSIONS

We report a multi-institutional collaboration to standardize the surgical management of bladder exstrophy. This effort increased the annual experience of each institution involved from threefold to ninefold and it has accelerated the physician knowledge base to ultimately benefit patient care.

Practice patterns and resource utilization for infants with bladder exstrophy: a national perspective

PURPOSE

Substantial variability exists in bladder exstrophy care, and little is known about costs associated with the condition. We define the care patterns and first year cost for patients with bladder exstrophy at select freestanding pediatric hospitals in the United States.

MATERIALS AND METHODS

We used the Pediatric Health Information System database to identify patients with bladder exstrophy born between January 1999 and December 2010 who underwent primary closure in the first 120 days of life. Demographic, surgical, postoperative and cost data for all encounters were assessed. Multivariate linear regression was used to examine the association between patient, surgeon and hospital characteristics and costs.

RESULTS

Of the 381 patients who underwent primary closure within the first 120 days of life 279 (73%) did so within the first 3 days of life. A total of 119 patients (31%) underwent pelvic osteotomy, including 51 of 279 (18%) who underwent closure within the first 3 days of life, 38 of 67 (56%) who underwent closure between 4 and 30 days of life, and 30 of 35 (86%) who underwent closure between 31 and 120 days of life (p = 0.0017). Median inflation adjusted, first year cost in United States dollars per patient was $66,577 (IQR $45,335 to $102,398). Presence of nonrenal comorbidity and completion of primary closure after 30 days of life increased first year costs by 24% and 53%, respectively. Increased post-closure length of stay was associated with greater costs.

CONCLUSIONS

At select freestanding United States pediatric hospitals the majority of bladder exstrophy closures are performed within the first 3 days of life. Most, but not all, patients undergoing closure after the neonatal period undergo osteotomy. The presence of nonrenal comorbidity and increased postoperative length of stay are associated with greater costs.

Dkk1 in the peri-cloaca mesenchyme regulates formation of anorectal and genitourinary tracts

Anorectal malformation (ARM) is a common birth defect but the developmental history and the underlying molecular mechanism are poorly understood. Using murine genetic models, we report here that a signaling molecule Dickkopf-1 (Dkk1) is a critical regulator. The anorectal and genitourinary tracts are major derivatives of caudal hindgut, or the cloaca.Dkk1 is highly expressed in the dorsal peri-cloacal mesenchymal (dPCM) progenitors. We show that the deletion of Dkk1 causes the imperforate anus with rectourinary fistula. Mutant genital tubercles exhibit a preputial hypospadias phenotype and premature urethral canalization.Dkk1 mutants have an ectopic expansion of the dPCM tissue, which correlates with an aberrant increase of cell proliferation and survival. This ectopic tissue is detectable before the earliest sign of the anus formation, suggesting that it is most likely the primary or early cause of the defect. Deletion of Dkk1 results in an elevation of the Wnt/ß-catenin activity. Signaling molecules Shh, Fgf8 and Bmp4 are also upregulated. Furthermore, genetic hyperactivation of Wnt/ß-catenin signal pathway in the cloacal mesenchyme partially recapitulates Dkk1 mutant phenotypes. Together, these findings underscore the importance ofDKK1 in regulating behavior of dPCM progenitors, and suggest that formation of anus and urethral depends on Dkk1-mediated dynamic inhibition of the canonical Wnt/ß-catenin signal pathway.

The impact of electrocautery method on post-operative bleeding complications after non-newborn circumcision and revision circumcision

PURPOSE

We evaluated post-operative bleeding complications in non-newborns following use of monopolar versus bipolar electrocautery for circumcision or revision circumcision.

MATERIALS AND METHODS

We retrospectively reviewed sequentially performed cases of circumcision and revision circumcision performed by nine pediatric urologists at our institution from 2005 to 2010. In order to incorporate both the monopolar and bipolar electrocautery experience for a single surgeon employing bipolar technique, sequential cases from 2002 to 2010 were reviewed. Variables assessed included age, procedure, method of electrocautery, skin approximation and dressing, and bleeding complications.

RESULTS

1810 patients that underwent either circumcision or revision circumcision were reviewed. Complete data was available for 1617 patients. Age at operation was a mean 3.7 ± 4.9 yrs and median 1.5 yrs. Return for bleeding complication for all surgeons, was 2/336 (0.6%) for bipolar and 28/1281 (2.2%) for monopolar (p = 0.0545). For the single surgeon using bipolar technique, returns were 2/336 (0.6%) for bipolar and 5/309 (1.6%) for monopolar (p = 0.2133). Returns per procedure type were 1/200 (0.5%) bipolar and 24/844 (2.8%) monopolar for primary circumcision (p = 0.0513), and 1/136 (0.7%) bipolar and 4/437 (0.9%) monopolar (p = 0.84) for revision. Four of 1617 (0.2%) patients returned to the operating room [4/1281 (0.3%) monopolar (p = 0.31)]. There was no difference in return to the operating room for circumcision versus revision.

CONCLUSION

Return for bleeding complications after circumcision and revision circumcision occurred more frequently after monopolar electrocautery compared to bipolar. However, there was no significant difference between the two electrocautery methods. Either form of electrocautery appears to be effective for this common pediatric urologic procedure.

Embryonic origin and remodeling of the urinary and digestive outlets

Separating digestive and urinary outlets is a critical step during mammalian embryogenesis. However, the natural history of these structures is poorly studied, and little is known about their embryonic origin. Here, we show that peri-cloacal mesenchymal (PCM) progenitors are the major source of these structures. Surprisingly, PCM progenitors also contribute to perineum, a structural barrier separating the urinary and digestive tracts, suggesting a potential role of PCM progenitors in establishing independent urinary and digestive outlets. We demonstrate that Six1 and Six2 are complementarily but asymmetrically expressed in the PCM progenitors. Deletion of these genes results in decreased cell survival and proliferation, and consequently in agenesis of the perineum and severe hypoplasia of the genital tubercle. Together, these findings suggest that PCM progenitors are the unexpected source of perineum and genital tubercle, and establish a basic framework for investigating normal and abnormal development of anorectal and genitourinary structures.

Urological complications and vesicoureteral reflux following pediatric kidney transplantation

PURPOSE

Ureteral complications of renal transplantation can dramatically impact renal outcomes. We studied whether complications are associated with preexisting genitourinary pathology or transplant using a deceased donor allograft.

MATERIALS AND METHODS

We retrospectively reviewed all patients undergoing renal transplantation at our institution between 2000 and 2010. We abstracted patient demographic details, donor type (living vs deceased), end-stage renal disease etiology, reimplant technique, stent use, preoperative and postoperative imaging, history of lower genitourinary pathology and postoperative complication management.

RESULTS

A total of 211 kidneys were transplanted into 206 patients (mean age 13.7 years, mean followup 4.6 years). Most patients (89%) underwent extravesical ureteroneocystostomy without stenting (97%), with roughly half (47%) of transplants being from living donors. Preexisting urological pathology was present in 34% of cases. Postoperative obstruction or extravasation occurred in 16 cases (7.6%), of which 15 were acute. Complications were not associated with donor type, preexisting urological pathology other than posterior urethral valves, surgical technique, etiology of end-stage renal disease or patient age. However, posterior urethral valves or other preexisting genitourinary pathology was not associated with an increased likelihood of genitourinary complications. Posterior urethral valves were associated with development of postoperative vesicoureteral reflux (OR 6.7, p = 0.004) but were not associated with stent placement, surgical technique, donor type or etiology of end-stage renal disease.

CONCLUSIONS

Patients with posterior urethral valves undergoing renal transplantation are at increased risk for postoperative vesicoureteral reflux but not for other acute surgical complications. There is no association between donor type, etiology of end-stage renal disease, surgical technique or patient age and increased complications.

The use of bladder neck reconstruction in bladder exstrophy

A major goal of bladder exstrophy (BE) management is achieving urinary continence, most commonly with surgical bladder neck reconstruction (BNR). This is a report of outcome of BNR after complete primary repair of exstrophy (CPRE). At our institution, patient history, ultrasound, cystogram (VCUG) and urodynamic study (UDS) were performed during a prospective evaluation of patients with BE. Dry interval of >3 hours was used as the definition of continence and dry interval <1-hour incontinence. Bladder capacity was measured at VCUG and/or UDS. UDS was also used to assess bladder compliance. From 1994 to 2010, we cared for 47 BE patients (31 male, 15 female) after CPRE. For patients ≥3 years after CPRE, BNR was performed in 9 of 22 (41%) male and 3 of 11 (27%) female patients. Mean age at BNR was 6.3 and 5.9 years for male and female patients, respectively. The mean (±SD) bladder capacity pre-BNR was 104.8 (±20.4 mL). There was a significant increase in capacity from pre-BNR to ≥1.5 years post-BNR (P = 0.013) and from <1.5 and ≥1.5 years post-BNR (P = 0.002). In conclusion, most patients with BE require BNR after CPRE. The need for BNR is more common in male patients.

Bladder neck reconstruction is often necessary after complete primary repair of exstrophy

PURPOSE

A major goal of bladder exstrophy management is urinary continence, often using bladder neck reconstruction. We report our experience with bladder neck reconstruction after complete primary repair of exstrophy.

MATERIALS AND METHODS

Patient history, ultrasound, voiding cystourethrogram, examination using anesthesia and urodynamics were performed during a prospective evaluation. Continence was assessed using the International Children's Continence Society classification and the dry interval. Bladder capacity was measured by examination using anesthesia, voiding cystourethrogram and/or urodynamics. Urodynamics were also done to assess bladder compliance and detrusor muscle function.

RESULTS

From 1994 to 2010 we treated 31 male and 15 female patients with bladder exstrophy after complete primary repair of exstrophy. Of patients 5 years old or older bladder neck reconstruction was performed after complete primary repair in 9 of 21 males (43%) and in 3 of 11 females (27%) at a mean age of 6.3 and 8.1 years, respectively. By the International Children's Continence Society classification 6 of 12 patients (50%) were continent less than 1.5 years after bladder neck reconstruction and 2 of 9 (23%) were evaluable 1.5 years or greater after reconstruction. Median bladder capacity was 100 ml before, 50 ml less than 1.5 years after and 123 ml 1.5 years or greater after bladder neck reconstruction. Three males and 2 females emptied via an appendicovesicostomy. Two boys underwent augmentation.

CONCLUSIONS

In our experience most patients with bladder exstrophy require bladder neck reconstruction after complete primary repair of exstrophy. The need for reconstruction is more common in males. Our rates of bladder neck reconstruction after complete primary repair of exstrophy and of continence after bladder neck reconstruction are similar to those in other reports.

Urodynamic abnormalities in toilet trained children with primary vesicoureteral reflux

PURPOSE

We investigated associated urodynamic abnormalities in toilet trained children with vesicoureteral reflux.

MATERIALS AND METHODS

A total of 298 toilet trained children with primary vesicoureteral reflux underwent urodynamic evaluation. Urodynamic parameters were reviewed and correlated with age, gender, presence of lower urinary tract symptoms and reflux severity.

RESULTS

Symptomatic lower urinary tract symptoms were present in 111 children (37.2%, group 1). Children with lower urinary tract symptoms had significantly decreased severity of vesicoureteral reflux compared to children without these symptoms (187 patients, group 2). The majority of the patients had normal early bladder compliance regardless of presence of lower urinary tract symptoms or reflux grade. On the other hand, decreased late bladder compliance was more common in group 1 vs group 2. Ratio of cystometric bladder capacity to expected bladder capacity was higher in group 2. Detrusor overactivity was observed in 28.5% of the children, and the incidence was significantly higher in group 1 vs group 2, and in mild vs moderate or severe reflux. Dysfunctional voiding from bladder sphincter dyscoordination was seen in 32% of children 2.5 to 4 years old with vesicoureteral reflux and lower urinary tract symptoms, compared to 8% in children 5 to 16 years old.

CONCLUSIONS

The presence of lower urinary tract symptoms in children with vesicoureteral reflux correlated well with some urodynamic findings suggestive of overactive bladder and negatively correlated with reflux severity. In contrast, dysfunctional voiding was more common in younger children with reflux and lower urinary tract symptoms. These findings suggest that treatment of voiding dysfunction should be directed toward the specific type of abnormality in children with vesicoureteral reflux.

Management of recurrent urethral strictures after hypospadias repair: is there a role for repeat dilation or endoscopic incision?

OBJECTIVE

Urethral strictures are among the most common complications after hypospadias repair. We report our 10-year experience with endoscopic incision or dilation of urethral strictures after hypospadias repair, to determine the best management technique.

METHODS

All cases of urethral strictures after hypospadias repair treated with direct vision internal urethrotomy (DVIU), dilation or urethroplasty at our institution from 1997 to 2007 were included. Records were reviewed and clinical parameters analyzed. Data were statistically analyzed to identify risk factors for stricture recurrence after initial or subsequent treatment(s).

RESULTS

Of 2273 patients, 73 were treated for a postoperative urethral stricture and 15 others were referred for stricture treatment. Of these 88 patients, 39 were treated with initial dilation or DVIU and 49 underwent urethroplasty or reoperative hypospadias repair. Fifteen (38%) of the patients treated with initial DVIU or dilation showed no recurrence. Of the patients that did have a recurrence, a repeat DVIU or dilation had a success rate of 17% with no difference in success between these two groups. Choice of therapy between repeat dilation/DVIU and urethroplasty at the second procedure showed a statistically significant higher success rate in the urethroplasty group (67% vs 17%, P=0.03).

CONCLUSION

Although numbers are small, our data suggest that if there is recurrent stricture after initial DVIU/dilation then a formal urethroplasty has a significantly higher success rate than repeat DVIU/dilation.