Growth in Boys with Posterior Urethral Valves

Current strategies to predict and manage sequelae of posterior urethral valves in children

Posterior urethral valves (PUV) constitute a significant urological cause of chronic kidney disease (CKD) in children. The condition is characterised by the unique pathophysiology of the evolution of bladder dysfunction after relief of obstruction, which contributes to CKD. Improvements in prenatal diagnosis followed by selective foetal intervention have not yet produced improvement in long-term renal outcomes, although better patient selection may alter this in the future. Proactive management with surveillance, pharmacotherapy, timed voiding, double voiding, and/or assisted bladder-emptying, is being increasingly offered to those with severe bladder dysfunction and has the potential of reducing the burden of renal disease. Clinicians are currently able to counsel regarding the prognosis using serum creatinine and other emerging markers. However, much of this work remains to be validated. Satisfactory graft survival rates are now reported with aggressive management of bladder dysfunction in children who are candidates for renal transplantation. Knowledge gaps exist in identifying early markers of renal injury, risk stratification, and in understanding patient and carer perspectives in PUV.

Intermittent voiding per urethra as an indicator of cutaneous vesicostomy malfunction

PURPOSE

To present a new approach for management of cutaneous vesicostomy (CV) prolapse, with special emphasis on normal appearing vesicostomy may be malfunctioning. To introduce the application of temporary stoma-free drainage as a diagnostic and therapeutic tool.

MATERIALS AND METHODS

From December 2000 to September 2006, 66 children (61 males and 5 females) with CV were studied. The mean age at vesicostomy was 7 months (range 1-30), and the main underlying disease was posterior urethral valves (in 45 children, 68%). Indications for CV included significant hydroureteronephrosis (HUN) and recurrent urinary tract infection. Patients were followed up for complications and were treated based on our institutional approach. All patients with persistent upper tract dilatation and micturition per urethra underwent temporary bladder (via stoma) free drainage. Patients with stomal stenosis were managed either by a revision surgery or by simple dilatation and intermittent catheterization. Purse string suturing was applied in mucosal prolapses as the first choice.

RESULTS

The complications were observed in 21 patients (31%), including twelve stomal stenosis, nine severe mucosal prolapses, and two recurrent urinary infections. HUN and significant voiding per urethra persisted following initial CV in 19 out of 66 patients (29%), eleven of which having normal appearing CVs. Seventeen of these patients were managed by temporary stoma-free drainage (accompanied by purse string suturing in mucosal prolapse), and two patients with severe stenosis underwent surgical revision. Temporary stoma-free drainage improved HUN in 94% of patients (16 of 17).

CONCLUSIONS

Voiding per urethra is an indicator of CV malfunction, and temporary stoma-free drainage can be a diagnostic and therapeutic option in such children. A seemingly open CV may still be malfunctioning, and ureterovesical or intravesical obstructions should be considered if HUN does not improve following temporary stoma-free drainage.

Posterior urethral valves: long-term outcome

Posterior urethral valves represent the most common cause of bladder outlet obstruction in infancy that impairs renal and bladder function. Long-term outcome of patients with previous PUV is evaluated. Patients over 18 years of age, treated from 1982 to 1995 before the age of 3 years were considered. Previous surgery, renal function, bladder activity, urinary incontinence, and fertility/sexual activity were evaluated. Clinical interview, creatinine clearance, uroflowmetry with ultrasound post-void urine residue, and self-administered questionnaire were recorded. Out of 45 identified records, 24 patients (53.3%) accepted to be enrolled (age 18-34 years, mean 23 years). The mean follow-up was 19.5 years (16-30 years). Out of the 21 excluded patients, 20 did not reply to the clinical interview and 1 died at age of 6 years. All the 24 patients had early endoscopic section of PUV; nine also received transient ureterocutaneostomy or vesicostomy. Ureteroneocystostomy was performed in five patients and ureterocystoplasty with unilateral nephrectomy in two. At follow-up chronic renal failure was detected in 13 patients (54.1%) and 9 (37.5%) had arterial hypertension. End-stage renal disease developed in five patients (20.8%): three had successful renal transplantation and two were in dialysis. Lower urinary tract symptoms were present in seven patients (29.1%). No significant fertility deficit and sexual dysfunction were observed in 23 patients, while 1 patient was azoospermic. No paternity was reported so far. Long-term outcome of patients with previously treated PUV is mandatory. Kidney, bladder, and sexual functions should be monitored till adulthood to verify any modified behaviour.

Long-term outcomes in children treated by prenatal vesicoamniotic shunting for lower urinary tract obstruction

OBJECTIVE

Limited information is available about long-term outcomes in children treated prenatally for lower urinary tract obstruction. Our aim was to evaluate outcomes in children treated in utero with vesicoamniotic shunts.

METHODS

Clinical outcomes in 20 pregnancies with a singleton male fetus, oligo/anhydramnios, and lower urinary tract obstruction were studied using chart review and phone and written clinical questionnaire for parents, pediatricians, and urologists.

RESULTS

Overall 1-year survival was 91%. Two neonatal deaths occurred from pulmonary hypoplasia. Mean gestational age at delivery was 34.6 weeks, mean days from shunting to delivery were 84.4, and mean birth weight was 2,574 g. Prenatal urinary prognosis was good in 13, borderline in 2, and poor in 3 of the survivors. Mean age at follow-up was 5.83 years. Posterior urethral valves were confirmed in 7 males, urethral atresia in 4, and prune belly syndrome in 7. Eight children had acceptable renal function, 4 had mild insufficiency, and 6 required dialysis and eventual renal transplant. Eleven children had normal bladder function with spontaneous voiding, 6 required catheterization, and 1 child still had a vesicostomy. Height and weight were below the 25th percentile in 9 children. Persistent respiratory problems were present in 8, musculoskeletal problems in 9, and frequent urinary tract infections were reported in 9. Health-related quality of life results in our group with lower urinary tract obstruction were similar to those in a healthy child population.

CONCLUSION

Male children who underwent prenatal bladder shunting were neurodevelopmentally normal. Although one third of the surviving babies required dialysis and transplantation, the majority have acceptable renal and bladder function and report satisfactory quality of life.

LEVEL OF EVIDENCE

III.

LONG-TERM FOLLOWUP OF BILATERAL HIGH (SOBER) URINARY DIVERSION IN PATIENTS WITH POSTERIOR URETHRAL VALVES AND ITS EFFECT ON BLADDER FUNCTION

PURPOSE

Although valve ablation is the treatment of choice in patients with posterior urethral valves (PUV), temporary high (ureterostomy) diversion remains controversial. In this study we evaluated the effect of bilateral Sober high urinary diversion on renal and bladder function.

MATERIALS AND METHODS

We retrospectively reviewed the records of 36 patients with PUV who underwent bilateral Sober-type diversion. Following valve ablation urodynamic studies were done in all patients after diversion and repeated after ureterostomy closure. The mean duration of diversion was 55 months. Vesicoureteral reflux (VUR), renal dysplasia, serum creatinine during followup and urodynamic parameters were recorded.

RESULTS

All patients underwent endoscopic valve ablation. Renal function impairment at the end of followup was present in 15 patients. Renal dysplasia was found in 10 patients, while VUR was present in 16 at the time of the first urodynamic studies. Urodynamic studies after ureterostomy closure showed well preserved bladder capacity or compliance in 80% and 69% of cases, respectively. About a third of patients showed increased capacity and normal compliance. Univariate analysis showed that VUR, urinary tract infection and renal dysplasia significantly correlated with impaired renal function. On multivariate analysis renal dysplasia was an independent prognostic factor for poor prognosis.

CONCLUSIONS

In patients with PUV temporary high diversion of the Sober type does not have a negative influence on bladder function. It immediately releases high intrarenal pressures but only improves renal function temporarily and may contribute to postpone the time of end stage renal failure. Renal dysplasia dictates long-term renal outcomes in this group.

Initial and long-term management of posterior urethral valves

Posterior urethral valves are the most common cause of congenital obstructive uropathy, resulting in renal failure in childhood. Nowadays, in most cases, diagnosis is suggested by antenatal ultrasound. However, antenatal intervention has not resulted in a significantly improved outcome. Endoscopic valve ablation is the initial treatment in most of these neonates, but others procedures, like vesicostomy or ureterostomy, can also be justified in some particular cases in order to improve renal function prognosis. Different factors like bladder dysfunction, VUR, polyuria and proteinuria, can be responsible for the slow and progressive deterioration in renal function that some of these patients show over the years. By treating them all, we may prevent or delay the onset of end stage renal disease.

Initial management of complex pediatric disorders: prunebelly syndrome, posterior urethral valves

Prunebelly syndrome and posterior urethral valves are conditions of detrusor dysfunction associated with antenatal urethral obstruction. The resultant severe hydroureteronephrosis and renal dysplasia initiate a sequence potentially leading to renal failure. This article reviews clinical features and explores neonatal evaluation and treatment for both conditions. A comprehensive approach to initial management aimed at optimal renal preservation and bladder rehabilitation is proposed.

WHEN CAN PERSISTENT HYDROURETERONEPHROSIS IN POSTERIOR URETHRAL VALVE DISEASE BE CONSIDERED RESIDUAL STRETCHING?

PURPOSE

Persistent hydroureteronephrosis (HUN) is often seen in boys with a history of a posterior urethral valve even years after valve ablation and it is often assumed to represent residual stretching. We determined the association of HUN with urodynamic abnormalities, the effect on HUN of treating these abnormalities and when persistent HUN could be considered residual stretching.

MATERIALS AND METHODS

Of 71 patients with a posterior urethral valve evaluated after valve ablation 20 (28.2%) had persistent HUN in a total of 32 renal units (RUs). The degree of HUN was graded as mild, moderate or severe. Videourodynamics were performed in all patients with persistent HUN and abnormal urodynamic findings were aggressively treated. HUN was then reassessed and categorized as resolved, improved or unchanged.

RESULTS

Abnormal urodynamic findings, primarily hypocompliance and instability, were noted in all 20 patients with HUN. All patients compliant with treatment showed dramatic improvement or complete resolution of abnormal urodynamic parameters. The 32 RUs with persistent HUN were initially graded as mild (8), moderate (13) and severe (11). HUN resolved in 15 RUs and improved to a lower grade in 11 in 26 of the 27 RUs (96.3%) in the 17 patients compliant with treatment. The 3 boys (5 RUs) who were noncompliant with treatment had neither decreased HUN nor improved urodynamic parameters. The 12 of 27 RUs (44.4%) in the treatment group in which HUN failed to resolve completely had no distal ureteral obstruction or identifiable persistent urodynamic abnormality and, thus, they can be labeled as having residual stretching.

CONCLUSIONS

Persistent HUN following valve ablation should not be considered residual dilatation until a thorough urodynamic evaluation has been done and any abnormal parameters are addressed. With correction of these abnormal parameters one can expect significant lessening of HUN and hopefully improved long-term preservation of renal function.

DOES MODE OF TREATMENT AFFECT THE OUTCOME OF NEONATAL POSTERIOR URETHRAL VALVES?

PURPOSE

A prospective study on the outcome of posterior urethral valves (PUV) was performed. The data analyzed were whether the modality of treatment (fulguration vs vesicostomy) affected renal function and somatic growth, and whether the presence of vesicoureteral reflux (VUR) and abnormal serum creatinine levels affected somatic growth.

MATERIALS AND METHODS

A total of 45 consecutive neonates were diagnosed and treated for PUV with fulguration (24) or vesicostomy (21) between 1997 and 2003. Postoperative stable creatinine values, renal function and somatic growth were recorded. Well tempered renal scans using diethylenetetraminepentaacetic acid were performed during the first and second years of life at followup. Standard anthropometric techniques and statistical methods were used to compute distance statistics for body weight and crown-heel length at age intervals of 3 months for year 1 and 6 months for year 2.

RESULTS

Of the patients 9 were lost to followup and 6 died in the first year of life due to renal failure. Preoperative and postoperative mean serum creatinine was 1.6 +/- 1.5 and 0.7 +/- 0.2 mg/dl, for the fulguration group and 1.7 +/- 1.5 and 0.9 +/- 0.7 mg/dl, respectively, for the vesicostomy group. In 10 patients renal function deteriorated or there was no improvement after treatment. With the advancement of age neonates with PUV showed normal increase in body weight and crown-heel length. Those with VUR were significantly shorter compared to neonates with no VUR at the end of year 2 of life (p <0.05). Patients with creatinine less than 1 mg/dl had significantly greater increase in body weight (at 3 and 6 months) as well as crown-heel length (at 3 and 9 months), respectively (p <0.05). Physical growth of the fulguration and vesicostomy groups remained substantially lower than that of their normal healthy counterparts. Newborns treated with vesicostomy did not have any breakthrough urinary tract infections. Although patients treated with vesicostomy were lighter and smaller initially (p <0.05), they were comparable to those treated with fulguration at the end of 2 years, thus demonstrating catch-up growth.

CONCLUSIONS

Our prospective study demonstrated that transurethral fulguration and vesicostomy are equally effective for neonatal valves and achieve similar renal function. Both groups showed retarded growth compared to healthy counterparts. Somatic growth was delayed by serum creatinine greater than 1.0 mg/dl and the presence of VUR. Vesicostomy seemed to help neonates catch-up the growth deficit in the first 2 years of life.

Posterior urethral valves: prognostic factors

OBJECTIVE

To determine which variables besides bladder dysfunction can help to predict the outcome of renal function in boys with posterior urethral valves (PUV).

PATIENTS AND METHODS

All 40 patients with PUV in this retrospective study were diagnosed and began treatment in our hospital within the first 3 months of life, and have had >or= 5 years of follow-up. At the time of diagnosis, 33 were in renal insufficiency (RI) and seven had normal renal function (RF). At the time of the study 16 were in chronic renal failure (CRF) and 24 had normal RF. We compared their RF (initial and during follow-up), vesico-ureteric reflux (VUR), urinary tract infection (UTI), proteinuria, hypertension, renal echogenicity, final patient age and initial management.

RESULTS

The mean serum creatinine values before and after initial treatment were worse in boys who developed CRF than in those who did not (P = 0.08); the mean glomerular filtrate rate (GFR) at 1 year old was 52 mL/min/1.73 m2 in the former and 102 in the latter (P < 0.001). Proteinuria was present during the follow-up in 79% of patients in CRF and in only 17% of those with normal RF. All patients who developed CRF had echogenic renal changes while only 53% of the others had (P < 0.01). Other variables showed no statistically significant differences (VUR, UTI, hypertension and final patient age). Of 33 patients in RI at diagnosis, nine were treated by valve ablation and 24 by temporary pyelo-ureterostomy. The initial mean serum creatinine value was worse in the latter than in the former (20.8 vs 13.0 mg/L). However, at 1 year old the mean GFR was better in the latter than in the former (P < 0.05). These GFR differences persisted during the first years of life but had disappeared by the fifth.

CONCLUSIONS

The most significant prognostic factor for the future development of CRF is the GFR at 1 year old. The onset of proteinuria during the follow-up is associated with a worse prognosis. Echogenic renal changes may help to identify those dysplastic kidneys that will develop RI. Neonatal boys in RI who underwent pyelo-ureterostomy had better RF during the first years of life than those who underwent valve ablation.

[Vesicostomy in children. Our experience with 43 patients]

INTRODUCTION AND OBJECTIVES

Cutaneous vesicostomy (CV) is a choice temporary urinary diversion technique for patients with upper urinary tract (URT) dilation, secondary to vesical o infravesical disease. The objective of this study is to share our experience in children undergoing such diversion, analysing its efficacy to prevent urinary infections, improve or resolve the ureterectasia, and stabilise or improve renal function; in short the functional and morphological recovery of URT.

MATERIAL AND METHODS

43 children, mean age 2.5 years (range: 1 month-14 years) with ureterohydronephrosis grade IV-V, persistent urinary infection and/or renal function impairment underwent cutaneous vesicostomy (Blocksom's technique in 36 and Lapides' procedure in the rest). Thirty subjects had neuropathic bladder (26 with secondary vesicoureteral reflux), 7 massive primary vesicoureteral reflux, and 6 posterior urethral valve.

RESULTS

All children (100%) with neurogenic bladder (30 cases), showed improvement of ureteral-pyelic-calyceal ectasia after the diversion, and 90% improved renal function with disappearance of vesiculoureteral reflux in 65%. Augmentation cystoplasty with gut was performed in 12 patients during vesicostomy closure, using Mitrofanoff's type diversion in 5 of them. The same continent diversion with cecal appendix was used in another 7 children as the only procedure. The remaining 11 children still retain their vesicostomy. In 5 of the 7 children with primary vesicoureteral reflux, the reflux disappeared and so the vesicostomy was closed. Reflux correction during the same surgical procedure was required for the other 2 children. Of the 6 children with posterior urethral valves, 2 received a renal transplant, one is in waiting list and the rest (50%) maintain an acceptable renal function. In the first year of follow-up, 4 patients developed symptomatic urinary infection that later disappeared. The rest had occasional asymptomatic bacteriuria that required no treatment. Complications included vesical prolapse due to ostomy in 4 patients, lithiasis in 3 and stomal stenosis in 2.

CONCLUSIONS

We consider vesicostomy to be the choice urinary diversion technique in cases of common section obstruction and/or non-obstructive ureterohydronephrosis in new-borns who do not improve with conservative treatment.

Obstructive nephropathy in children: long-term progression after relief of posterior urethral valve

BACKGROUND

Approximately one third of children with end-stage renal disease have the illness because of urinary tract malformations, obstructive uropathy, and hypoplasia/dysplasia. The significant drop in infant mortality from obstructive uropathies in recent decades, attributable to prenatal diagnosis with renal ultrasonography and coordinated surgical and medical care, necessitated a reevaluation of the long-term outcome.

METHODS

To that end, we examined the long-term progression of obstructive nephropathy after neonatal relief of posterior urethral valves in our center over a span of 21 years, with diagnosis and care being provided by the same pediatric and urology team.

RESULTS

The 10 consecutive cases of posterior urethral valves represented 7% of all patients with congenital malformative uropathies seen over this period. The following procedures were performed: primary valve ablation (90%) and vesicostomy (40%). Seventy percent of patients progressed to end-stage renal disease over a (mean +/- standard error of the mean) follow-up of 11.3 +/- 2.1 years. The linear plot of the log of the inverse of serum creatinine versus time suggested unrelenting progression. The rate of progression was rapid after serum creatinine exceeded 5 mg/dL but the rate was slow and steady from serum creatinine of 1.5 to 5 mg/dL.

CONCLUSIONS

To test the effect of a therapeutic intervention to ameliorate the rate of progression, this steady and prolonged progression of 0.5 mg/dL per year between serum creatinine concentration of 1.5 to 5 mg/dL would seem the optimal study.

Applications of the KTP laser in the treatment of posterior urethral valves, ureteroceles, and urethral strictures in the pediatric patient

PURPOSE

We describes our experience using the potassium titanyl phosphate (KTP)-532 laser in treating posterior urethral valves, ureteroceles, and urethral strictures in the pediatric patient.

METHODS

A retrospective chart review was performed from 1987 to 1997 on a total of 33 pediatric patients who underwent retrograde endoscopic treatment for posterior urethral valves (PUV), ureteroceles (UC), and urethral strictures using a KTP-532 laser.

RESULTS

Overall, our success rate was excellent in the treatment of valves and ureteroceles. With a mean follow-up of three years in the PUV group, no urethral strictures of micturation abnormalities were seen. The majority of ureteroceles were decompressed and only half of our patients required and additional procedure. Our experience with urethral strictures, however, was not as promising. All of these patients ultimately required open urethral reconstruction.

CONCLUSION

The desirable thermal characteristics of the KTP laser, along with minimal complications and the availability of delicate pediatric endoscopic instruments have made this operation optimally suited for treating posterior urethral valves and ureteroceles in infants. However, the advantages for treating urethral strictures in children with the laser still remains to be established.

Evolution of upper urinary tract and renal function in patients with posterior urethral valves

From January 1972 to June 1993, 166 patients with posterior urethral valves (PUV) were treated in our surgical department, 59 with a milder form of PUV (upper urinary tract [UUT] complication rate 29%) and 107 with a severer form (UUT complication rate 96.3%). Only the latter group was studied for long-term (mean 9.3 years) evaluation of the UUT and renal function. A temporary vesicostomy was the primary treatment in 25 patients. Indications for temporary diversion were very young age and/or low birth weight, severe and bilateral UUT complications, and severe renal damage. All the other patients were treated by primary endoscopic valve fulguration. After removal of the lower urinary tract obstruction, vesicorenal reflux (VRR) resolved spontaneously or was ameliorated in 59.2% of the renal units. Spontaneous normalization or evident amelioration were found at long-term follow-up in nearly 70% of dilated, non-refluxing ureters. Ureteral reimplantation was performed on 41 of the 202 dilated or refluxing ureters (surgical rate 20.3%). The surgical failure rate requiring reoperation was 5% (2/41). The prerequisite for successful reimplantation was a large-capacity, stable, and compliant bladder. Ten nephroureterectomies were carried out for unilateral, massive VRR and renal dysplasia; 1 late nephrectomy was performed for arterial hypertension. The evolution of renal function showed statistically significant overall improvement, which was more evident in patients diagnosed and treated in the 1st month of life (P = 0.000) than in those treated between 1 and 12 months (P = 0.004) or after 1 year of age (P = 0.025). Renal function considerably improved in the vesicostomy group (P = 0.000). Thirteen patients (12.4%) are now either dead (2) or have end-stage renal disease (6) or chronic renal insufficiency evolving toward end-stage renal disease (5); 5 of these 13 were treated by vesicostomy in the first days or months of life, and at presentation the glomerular filtration rate (GFR) was less than 25 ml/min . 1.73 m(2). Determination of basic GFR and, even more, functional renal reserve is relevant in predicting the long-term evolution. In the author's opinion, vesicostomy is the procedure of choice in very ill newborns or infants. Aggressive management with early surgical reconstruction is rarely justified, because frequently UUT complications resolve spontaneously or clearly improve, and their surgical treatment has limited and very precise indications.

Cutaneous vesicostomy in the young child: indications and results

With newer methods of managing lower urinary tract pathology in the young child, the role of cutaneous vesicostomy may be changing. This prompted a review of 50 consecutive patients treated with initial vesicostomy at our center over ten-year period. These children underwent vesicostomy diversion at a median age of 5.8 months and, of the 34 vesicostomies which have been subsequently closed, for a median duration of twenty-five months. Our indications agree with series reported previously and include patients with meningomyelocele, posterior urethral valves, or other forms of congenital or acquired lower urinary tract anomaly or dysfunction, along with complicating factors such as vesicoureteral reflux, recurrent infections, and/or renal deterioration. However, we also have identified a major group--those with primary gross vesicoureteral reflux--not previously included in detail. Follow-up averaged thirty-eight months. Improvement or stabilization of upper urinary tracts was achieved in over 90 percent of cases, and this trend continued after vesicostomy closure. As well, cutaneous vesicostomy allowed ureteral dilation to normalize, decreasing the degree of reflux and need for subsequent ureteral tapering and reimplantation at closure. Finally, though our stomal revision rate of 20 percent is high, modified techniques are being pursued.

Radiographic and serologic correlates of azotemia in patients with posterior urethral valves

A retrospective statistical analysis with a minimum followup of 10 years was done on 102 patients who presented in early childhood with posterior urethral valves. All patients were treated with initial bladder drainage. Factors correlating with the development of renal failure were evaluated. No patient with a normal kidney on 1 side had renal failure. Calculated glomerular filtration rate was significantly higher in patients who retained adequate renal function (80.7 +/- 17.8 ml. per minute per 1.73 m.2), as compared with those who had renal failure (18.6 +/- 9.6 ml. per minute per 1.73 m.2). Patients with renal failure also had a significantly higher serum creatinine level at stabilization (2.0 +/- 0.8 mg./dl.) than those who had adequate renal function (0.5 +/- 0.2 mg./dl.). The presence of bilateral high grade vesicoureteral reflux, hydronephrosis and nonfunction was significantly higher in patients with renal failure. Patient age at presentation was not a significant factor. These data represent a guideline for the prognosis and management protocols of infants with dilated upper urinary tracts and posterior urethral valves.

Influence of initial therapy on progression of renal failure and body growth in children with posterior urethral valves

Children with posterior urethral valves are at high risk for renal failure and growth retardation. It has been proposed that the type of initial surgical treatment (that is primary ablation versus high diversion) can affect the outcome of children with posterior urethral valves. We evaluated 43 children with posterior urethral valves treated and followed at our hospital from 1975 to 1990 (17 since birth and 26 referred patients). A total of 19 patients was treated by a high urinary diversion, (high urinary diversion group), 19 were treated by primary fulguration and 2 by vesicostomy (fulguration and vesicostomy group), and 3 underwent fulguration and unilateral diversion (mixed treatment group, excluded from study). The clinical outcome and body growth were compared for the high urinary diversion, and fulguration and vesicostomy groups. A normal stature (above the 25th percentile) was reached by 4 patients (21%) from the high urinary diversion group and 11 (52%) in the fulguration and vesicostomy group. This difference was not statistically significant. In contrast, renal function was predictive of body growth: 73% of the children with normal serum creatinine and 20% of the children with renal failure achieved a normal stature (p less than 0.05). One patient from the mixed treatment group died of pulmonary hypoplasia. We conclude that the type of primary surgical treatment (fulguration and vesicostomy or high urinary diversion) did not influence progression of renal failure or body growth in children with posterior urethral valves. Regardless of the surgical or medical treatment, which can greatly influence mortality, renal failure developed in almost 50% of the children with posterior urethral valves.

Laser treatment of posterior urethral valves in neonates

The posterior valves of 13 neonates were resected using the neodymium:YAG laser in retrograde transurethral endoscopy. There were no strictures or other complications.

Long-term urinary continence and renal function in neonates with posterior urethral valves

Posterior urethral valves are known to be associated with considerable morbidity and mortality especially in the neonate. Recently the role of bladder dysfunction in the pathophysiology of renal function impairment and urinary incontinence after valve ablation has been questioned. From 1976 to 1986 we treated 50 male newborns with posterior urethral valves at our institution. Initial treatment in all cases consisted of bladder drainage by a urethral catheter, and correction of existing fluid and electrolyte abnormalities. Subsequent treatment was dictated by the degree of upper tract abnormalities and it included valve ablation alone in 24 patients, vesicostomy and later valve ablation in 8, valve ablation and later upper tract reconstruction in 14 and cutaneous ureterostomy in 4. Followup ranges from 2 to 12 years (mean 6.8). Long-term renal functional impairment was related to the serum creatinine at age 1 year. If the serum creatinine was below 1.0 mg.% all patients (31) had normal values at long-term followup and if it was greater than 1.0 mg.% (19) then only 7 patients had normal values at followup. Urinary continence was assessed in 42 patients and it was normal in 34 (81%). The etiology of incontinence in the remaining 8 patients was bladder dysfunction in 6 and sphincter incompetence in 2. Those patients with urinary incontinence also had a high incidence of upper tract abnormalities (6 of 8, 75%) compared to continent valve patients (10 of 34, 29%).

The management of posterior urethral valves by initial vesicostomy and delayed valve ablation

We managed 32 neonates and infants with temporary vesicostomy and delayed valve ablation. The criterion on which successful management was gauged was estimated creatinine clearance. Renal failure or death occurred in 30% of the patients and 7% required transplantation. There was no apparent difference between our patients managed initially with vesicostomy and other series managed initially with valve ablation in preventing the complications of posterior urethral valves.

Primary vesicoureteral reflux in blacks with posterior urethral valves: does it occur?

Primary vesicoureteral reflux (VUR) is thought to be largely independent of obstruction. Therefore, in patients with urethral obstruction due to posterior urethral valves (PUV) the occurrence of VUR is coincidental. In addition, primary VUR is reported to be uncommon in black children. If these two premises are correct, then primary VUR should be rare in black males with PUV. To test this hypothesis, we reviewed the medical records and radiographs of 43 males with PUV. Twenty-one of the 37 non-black males with PUV had VUR, of which 67% was primary and 33% was secondary. Three of the six blacks with PUV had VUR of which all was secondary. Thus, blacks with PUV lend credence to the theory that primary VUR is not caused by obstruction and support the observation that primary VUR is rare in black children, even those with PUV.

Neodymium:YAG laser ablation of posterior urethral valves

We report successful neodymium:YAG laser ablation of posterior urethral valves in 6 boys. No strictures or incontinence resulted.

Posterior urethral valves in the newborn: treatment and functional results

Between 1977 and 1984, 30 newborn boys were diagnosed and treated with posterior urethral valves. Presenting symptoms varied but included respiratory distress, oligohydramnios, urinary ascites, abdominal mass, urinary retention, and renal insufficiency. Diagnostic modalities consisted of excretory urography and voiding cystourethrography in all patients and ultrasonography in 20 (12 prenatal). Treatment consisted of valve ablation alone in 14, vesicostomy and later valve ablation in 4 premature infants, valve ablation and later upper tract reconstruction in 8, loop ureterostomy in 2, and valve ablation and immediate reconstruction in 2. Follow-up in our patients has demonstrated that even though surgical reconstruction may be technically successful, ultimate functional outcome may be dependent upon the degree of renal impairment at presentation.

Vesicoureteral reflux and reflux nephropathy

Vesicoureteral reflux (VUR) is mainly a primary phenomenon due to incompetence of the ureterovesical junction, mostly affecting a pediatric population. During micturition cystourethrography (MCU) reflux into the kidney--intrarenal reflux (IRR)--is occasionally seen. In areas with IRR the kidney surface may subsequently be depressed and the papillae retracted (reflux nephropathy (RN]. VUR may lead to hypertension and/or end-stage renal failure. Most commonly, VUR is discovered during evaluation for urinary tract infection, but it may also be present in patients with hypertension, toxemia of pregnancy, chronic renal failure and proteinuria, and it may be found in siblings of patients with VUR. For the time being VUR is demonstrated at radiographic MCU, whereas RN is diagnosed by demonstration of focal scars and of abnormal parenchymal thickness at urography. In children with VUR and no abnormalities of calyces or parenchymal defects standardized measurement of the parenchymal thickness at three sites may identify kidneys which are likely to develop focal scars. Quantitation of focal scarring should be performed in connection with a measure of the overall kidney size. The occurrence of IRR is dependent of the papillary morphology, intrapelvic pressure and urine flow. There may be an important relationship between renal ischemia and IRR in producing a 'vicious circle of deleterious effects' which, combined with parenchymal extravasation, may lead to RN. Treatment of VUR includes medical and surgical management. Since renal scarring may occur in infancy, prevention should focus on infants and young children. Infants and young children with severe VUR may have normal urograms. Therefore a MCU should also be performed, preferably with the recommended standardized technique.

The variable effect of posterior urethral valves as illustrated in identical twins

To our knowledge, we report the second instance of posterior urethral valves in identical twin boys. Initial symptoms, age at presentation and radiographic findings were different in each boy, and reflect the varying nature of this congenital anomaly. Although the brothers are identical twins from the same environment with identical Rh and ABO blood groupings and identical HLA haplotypes, developmental differences have been marked.

Fetal urinary tract obstruction: is active intervention before delivery indicated?

Obstruction of the urinary tract was diagnosed by ultrasound in four fetuses at 16-30 weeks: three of these diagnoses were confirmed after delivery; the fourth fetus had multicystic kidneys with hydroureter and hydronephrosis but no obstruction. The fetus with obstruction diagnosed at 16 weeks was terminated: it had lung hypoplasia with the prune-belly syndrome. The other two fetuses with obstruction were diagnosed at 25 and 34 weeks; the urinary tracts of both were drained for 5-14 days with reduction of distension. Both were born alive but that diagnosed at 25 weeks died of lung hypoplasia, the other survived, required nephrectomy and at the age of 3 is small but developing normally. Fetal urinary tract obstruction may prevent normal development of the lungs, be associated with other anomalies which cannot be diagnosed before delivery and retard infant development in survivors. Drainage of the dilated urinary tract does not harm the fetus or mother but has not been shown to improve neonatal survival or infant development.

Bilateral percutaneous nephrostomy as adjunctive treatment in a newborn infant with posterior urethral valves

A case report illustrates that percutaneous nephrostomy is a simple alternative to surgical ureterostomy when temporary supravesical diversion is necessary in a newborn with posterior urethral valves.