Transplantation in children with end stage renal disease of urologic origin

Bladder Augmentation (Enterocystoplasty): the Current State of a Historic Operation

PURPOSE OF REVIEW

The goal of this paper was to evaluate the current use of enterocystoplasty, a historical operation for bladder dysfunction but with continued and increasing modern relevance.

RECENT FINDINGS

Since the advent of third line neuromodulation techniques for neurogenic and idiopathic overactive bladder (OAB), the usage of enterocystoplasty has decreased. However, this procedure continues to be utilized in pediatric urology patients and the most refractory OAB patients. Adult urologist should be familiar with this operative technique in an effort to manage pediatric patients transitioning to adulthood. Minimally invasive techniques for this surgical procedure have been described with very limited outcome data. It is important for all urologists to be familiar with enterocystoplasty, both technically and with the unique needs of these patients postoperatively. Further studies evaluating the outcomes of this procedure in idiopathic overactive bladder patients and efforts to standardize recommendations for neurogenic bladder patients will help guide care in the future.

Indications for Augmentation Cystoplasty in the Era of OnabotulinumtoxinA

Overactive bladder (OAB) with or without a neurogenic etiology that is refractory to conventional first-, second-, and third-line therapies is a challenging condition that typically leaves the physician and the patient with few options. Historically, treatment for patients who did not respond to any of the few pharmacologic choices focused on more invasive surgical options--specifically, augmentation cystoplasty (AC). In 2011 and 2013, the Food and Drug Administration (FDA) approved intradetrusor injection of onabotulinumtoxinA for the treatment of neurogenic detrusor overactivity (NDO) and idiopathic detrusor overactivity (IDO), respectively. Since then, a dramatic decline in the use of AC has called into question its utility in the treatment algorithm of this difficult patient population. The purpose of this paper is to review the current body of literature in order to outline the circumstances in which AC is still a relevant therapeutic option.

The past, present and future of augmentation cystoplasty

What's known on the subject? And what does the study add? There is a wealth of evidence on the development, indications, outcomes and complications of augmentation cystoplasty (AC). Over the last decade, new evidence has been emerging to influence our clinical practice and application of this technique. AC is indicated as part of the treatment pathway for both neurogenic and idiopathic detrusor overactivity, usually where other interventions have failed or are inappropriate. The most commonly used technique remains augmentation with a detubularised patch of ileum (ileocystoplasty). Controversy persists over the role of routine surveillance following ileocystoplasty for the detection of subsequent bladder carcinoma; however the indication for surveillance after gastrocystoplasty is clearer due to a rising incidence of malignancy in this group. Despite a reduction in the overall numbers of AC operations being performed, it clearly still has a role to play, which we re-examine with contemporary studies from the last decade.

Kidney transplantation with two donor ureters in patient with previous ileogastric conduit

The purpose of our publication is to focus upon the technical aspects of a rare combination of kidney transplant with two donor ureters in a patient with neurogenic bladder and previous reconstruction of a continent ileogastric conduit.

Pediatric renal transplantation

Renal transplantation in children is a most rewarding treatment that dramatically changes the overall health and lifestyle of children with ESRD. Complexities in different aspects of renal transplantation in children are obvious. Optimum technical conditions and drug therapy must be provided for the success of renal transplantation. Application of recent advances in immunology and long-term care to clinical transplantation continue to improve graft and patient survival rates. Optimization of growth and development also can be improved with the use of rhGH.

Enterocystoplasty in renal transplantation candidates: urodynamic evaluation and outcome

In anticipation of renal transplantation 11 patients with end stage renal disease and small volume, poorly compliant bladders underwent enterocystoplasty. The etiology of bladder dysfunction included myelodysplasia in 4 patients, posterior urethral valves in 4 and vesicoureteral reflux in 3. Mean patient age at the time of bladder augmentation was 16.4 years (range 10 to 28). Detubularized bowel segments were used in all patients and included ileum in 7, ileocecal segment in 3 and sigmoid in 1. Urodynamic evaluation before and after enterocystoplasty demonstrated marked improvement in bladder capacity and compliance. These 11 patients have received 13 renal transplants with an 85% graft survival at a mean followup of 30.1 months. No bladder ruptures or other perioperative complications have occurred. All patients remain continent on clean intermittent catheterization. Our experience suggests that enterocystoplasty is a safe and effective method of restoring lower urinary tract function in the patient with end stage renal disease and a small, noncompliant bladder.

Results of renal transplantation in boys treated for posterior urethral valves

The results of renal transplantation in boys treated for posterior urethral valves were evaluated and compared with a matched control group. Patient and graft survival was equal in both groups, although serum creatinine levels were slightly higher in the posterior urethral valves group. Postoperative complications, such as urinary tract infections, occurred more frequently in the posterior urethral valves group. Urodynamic evaluation was performed before transplantation in 11 of 20 patients. Adequate treatment of bladder dysfunction, such as poor compliance and/or hyperreflexia, is essential in diminishing the risks of secondary graft damage due to severe bladder dysfunction.

Urinary tract infections in children with posterior urethral valves after kidney transplantation

The records of 14 boys with posterior urethral valves who had renal failure and subsequently underwent renal transplantation were reviewed to determine the postoperative incidence of urinary tract infection relative to that of 29 male transplant children without valves, who served as controls. There were no significant differences between the posterior urethral valve patients and controls with regard to age, donor source, immunosuppression, followup after transplantation or mean calculated creatinine clearance. Vesicoureteral reflux was found in 1 child with posterior urethral valves and 3 of the children in the control group (p not significant). A total of 15 urinary tract infections occurred in 5 children (36%) with posterior urethral valves, for a rate of 1 per 30 patient-months of followup, and 6 urinary tract infections occurred in 2 controls (7%), for a rate of 1 per 216 patient-months of followup (p < 0.05). However, only 1 of 26 controls (4%) without vesicoureteral reflux had urinary tract infection, for a rate 1 per 1,144 patient-months (p < 0.01). Conversely, the rate of urinary tract infections in controls with vesicoureteral reflux was similar to that of children with posterior urethral valves. Of the 5 children with posterior urethral valves 4 had the initial urinary tract infection within 2 months of transplantation and 10 of 15 episodes occurred within the first 4 months. Antimicrobial prophylaxis did not appear to decrease the rate of infection in children with posterior urethral valves. A history of posterior urethral valves increases the frequency of urinary tract infection after renal transplantation but the usefulness of antimicrobial prophylaxis and the relationship to long-term graft function remain to be determined. Urinary tract infection rarely develops in other transplanted boys without vesicoureteral reflux.

Familial renal adysplasia

Renal dysplasia and agenesis as isolated findings are usually considered sporadic, noninherited abnormalities. We report three kindreds with familial renal adysplasia. Two or more children were affected in each of the families and at least one member--whether proband, sibling, or parent--had a clinically silent anomaly. Normal kidneys in the parents did not preclude the occurrence of renal adysplasia in more than one child. The empiric risks for offspring and first-degree relatives were 50% and 25%, respectively, suggesting a strong genetic factor such as a major dominant gene with variable expression. Because the disease appears to be genetic in some cases of renal adysplasia, careful screening of the proband's family, subsequent children, and pregnancies is important for the purpose of accurate genetic counseling.

Outcome of renal transplantation after urinary diversion and enterocystoplasty: a retrospective, controlled study

A total of 17 patients with intestinal urinary diversion of enterocystoplasty underwent renal transplantation between 1970 and 1988. Patient age ranged from 4 to 35 years (mean age 20 years). The patients were divided into 2 groups. In group 1 (10 patients, 2 of whom required retransplantation) the ureter of the transplanted kidney was implanted into an ileal (7) or colonic (1) conduit or enterocystoplasty (2). In group 2 (7 patients, 1 of whom required a second transplant) the diversion was taken down and the transplanted ureter was implanted into the defunctionalized bladder. There were 14 living related and 6 cadaveric kidneys transplanted. Graft survival rates were 58 and 87% in groups 1 and 2, respectively, with an over-all rate of 70% (14 of 20 kidneys). There was no statistical difference in the graft survival rate between the 2 groups. The complications in group 1 included ureteroileal anastomotic leak (3 patients), ureteroileal stenosis (1), calculus formation (1), urosepsis (1), hyperchloremic metabolic acidosis (1), and wound infection and dehiscence (1). There were no complications in group 2. Renal transplantation into a pre-existing urinary intestinal conduit or augmented bladder does not statistically adversely affect patient or graft survival. However, the complication rate is much higher when the ureter is implanted into an intestinal segment. Therefore, it is preferable whenever possible to implant the ureter into the native bladder.

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%).

Continent cutaneous Ileostomy (Kock pouch) prior to renal transplantation

Two patients in end-stage renal failure and with neurogenic bladders due to spina bifida complicated by myelomeningocele were considered for renal transplantation. One patient had had a right nephrectomy and urinary diversion via an ileal conduit; the other, after various external drainage procedures (cystostomy, bilateral nephrostomy), had had a tubular ileocystoplasty. Both underwent 2 surgical procedures prior to renal transplantation: in case 1 we performed a left nephrectomy and then ileal conduit removal + Kock pouch; in case 2 a bilateral nephrectomy was performed via 2 posterior incisions and then we removed the ileocystoplasty and formed the pouch. The continent ileostomy was formed according to the original technique with slight modifications. The patients have been followed up for 12 and 15 months after transplantation.

Ureaplasma urealyticum upper urinary tract infection: persistence and pathogenicity in a canine model

Ureaplasma urealyticum is an opportunistic pathogen, commonly isolated from the lower urogenital tract. Although U. urealyticum has been cultured from the upper urinary tracts of patients with interstitial renal diseases and struvite renal calculi, the precise role of ureaplasmas in upper tract diseases is unknown. To evaluate their potential significance in the etiology of renal diseases, we studied survival, multiplication, and pathogenicity of U. urealyticum in canine kidneys with experimentally induced hydronephrosis. After inoculation of the prototypic serovar (Type 8, strain 960) of U. urealyticum, seral urine specimens were obtained using a subcutaneously positioned nephrostomy catheter. Although U. urealyticum survived for less than 48 hours in canine urine in vitro, organisms persisted in the obstructed upper urinary tract for at least 21 days. Urinary pH of infected renal units increased to 7.5 to 8.5, a most unfavorable range for U. urealyticum in culture. Renal parenchyma had higher concentrations of ureaplasmas (8.7 X 10(3) to 9.5 X 10(4) CFU/gm.) than either renal pelvis tissue (1.0 X 10(3) CFU/gm.) or urine (6.5 X 10(3) CFU/ml.). Histologic studies demonstrated progressive interstitial inflammation in infected kidneys but similar changes were not apparent in obstructed, uninfected kidneys. The obstructed upper urinary tract appears to provide favorable conditions for ureaplasmas which may cause progressive interstitial inflammation in the absence of other pathogens.

Inhibition of protein glycosylation causes renal dysplasia in the chick embryo

The pathogenesis of renal dysplasia, a common congenital renal malformation, remains poorly understood. However, the disease is believed to represent failure of normal renal morphogenesis. Recently, it has been demonstrated that a shift in the composition of the extracellular matrix from an interstitial type to a basement membrane type heralds induction of the renal mesenchyme. In addition, 2 agents that inhibit glycosylation of extracellular matrix glycoconjugates, 6-diazo-5-oxonorleucine and tunicamycin, prevent induction of tubules in vitro. To investigate the relationship between failure of tubulogenesis and renal dysplasia experimentally, we used these inhibitors as potential teratogens and examined the resultant effects of the renal distribution of 2 extracellular matrix constituents: laminin, a basement membrane glycoprotein, and fibronectin, an interstitial glycoprotein. We documented the normal shift in the distribution of laminin and fibronectin during tubulogenesis. Fibronectin, prominent in undifferentiated mesenchyme, tended to disappear during development, while laminin appeared in increasing amounts within differentiating tubules. Renal rudiments (7 to 9 days of incubation) were exposed to tunicamycin, 6-diazo-5-oxo-norleucine or control media in vitro and then they were permitted to develop further as grafts in ovo. In 127 surviving grafts those treated at 8 days of incubation for 48 hours most often were dysplastic: 12 of 18 (67 per cent) tunicamycin versus 3 of 16 (19 per cent) control media (p less than 0.025) and 8 of 13 (62 per cent) 6-diazo-5-oxo-norleucine versus 2 of 16 (12 per cent) control media (p less than 0.025). Most rudiments exposed to 6-diazo-5-oxo-norleucine or tunicamycin for only 24 hours at 8 days of incubation or at 7 or 9 days of incubation were not dysplastic. Finally, 4 chick kidneys with induced dysplasia and 2 fresh surgical specimens with dysplasia were stained for laminin and fibronectin with indirect immunofluorescence and all showed abnormal distributions of both glycoproteins. These results support existing theories that dysplasia is the result of a disruption in normal epithelial-mesenchymal interaction during the induction of renal tubules.

Renal transplantation in end stage renal disease patients with existing urinary diversion

From 1971 to 1984 renal transplantation was performed in 20 patients with end stage renal disease who presented with an existing form of urinary diversion. These patients were evaluated with a cystometrogram, voiding cystourethrogram and cystoscopy. In some cases bladder function was studied further by cycling through a suprapubically placed catheter. The bladder was considered unstable in 13 patients and undiversion was done at transplantation. The period of prior diversion ranged from 3 to 20 years (mean 12.7 years). There were no surgical complications postoperatively and normal bladder function returned in all patients. Currently, 8 patients have a functioning renal allograft 16 months to 9 years after transplantation (mean 4.2 years). Seven patients were considered to have a nonusable bladder owing to severe neurogenic disease or refractory contracture. In these patients transplantation was done into a pre-fashioned intestinal conduit (5) or cutaneous ureterostomy (2). Currently, 4 patients have a functioning renal allograft 16 months to 6.2 years after transplantation (mean 3.8 years). Transplantation candidates who present with an existing form of urinary diversion should be evaluated carefully, since many will have a usable bladder. Regardless of whether the bladder is usable, transplantation can be performed safely with no increased surgical or immunological risk.

Obstructive uropathies diagnosed in utero. The postnatal outcome--a study of 43 cases

The ultrasonic antenatal diagnosis of obstructive uropathies is now common. This study of 43 cases in which the mean follow-up is more than 2 years already allows us to show the importance of early diagnosis. The importance of a thorough postnatal examination is emphasised as well as the importance of preventing urinary tract infection. Although relief of the obstruction in the neonatal period in many cases allows an excellent recovery due to the exceptional qualities of the urinary tract at this age, there remain serious uropathies associated with significant renal dysplasia, for which ultrasonic diagnosis in utero is still insufficient. The results obtained allow us to be optimistic regarding the prognosis for many of these children.

Pediatric renal transplantation

This article outlines the current status of pediatric renal transplantation and emphasizes a practical approach to patient management. It discusses two areas of renal transplantation in children in which results differ significantly between children and adults. These areas are renal transplantation in the very young child and transplantation in children with renal failure secondary to urologic disease.

Intermittent clean catheterization: an alternative to diversion in continent transplant recipients with lower urinary tract dysfunction

A total of 3 renal transplant recipients who were candidates for urinary diversion underwent successful transplantation using a planned program of intermittent clean catheterization. The urinary tract dysfunction was caused by a lower motor neuron neurogenic bladder, prune belly syndrome and myelodysplasia. The patients remain dry between catheterizations and maintain serum creatinine levels of 1.1, 0.8 and 0.5 mg. per cent, respectively, with a followup of 6 to 25 months. There has been only 1 urinary tract infection during 42 patient-months at risk while on self-catheterization. Pre-transplant urologic evaluation and patient education are mandatory. The ideal candidate for intermittent clean catheterization is a patient with a low pressure bladder that fails to empty and who is continent between catheterizations. Intermittent clean catheterization is a safe and effective alternative to diversion in continent transplant recipients with lower urinary tract dysfunction.

Renal transplantation in children with occult neurogenic bladders drained by intermittent self catheterisation

Children with neurogenic bladders have usually not been considered for renal transplantation because of the potential complications caused by chronic infections of the urinary tract. Two girls with occult neurogenic bladders who were practising intermittent self catheterisation were given renal transplants. Both took prophylactic antibacterial agents after transplantation, and both experienced infections at some stage, but none of these infections produced a deterioration in renal function. In one patient creatinine clearance fell and signs of obstruction appeared, but this was because the patient had been catheterising herself only two or three times a week. When she resumed catheterisation four times a day creatinine clearance rose and the urographic and renographic appearances returned to normal. These results suggest that, with adequate catheterisation and urinary chemoprophylaxis, infection is not a particular problem in children with bladder dysfunction who undergo renal transplantation.

The role of urinary obstruction in the genesis of renal dysplasia. A model in the chick embryo

Although obstruction of urinary drainage is the current pathogenetic mechanism believed responsible for renal dysplasia, the results of experimental studies have not uniformly substantiated this impression. To help resolve this issue, we evaluated the effect of obstruction of the urinary drainage of the embryonic kidney upon the later development of the kidney. We developed a model which allowed us to ligate the ureter surgically of the chick embryo before and after the appearance of nephrons. Initially, the normal morphologic features of renal development were studied in 22 embryos at various stages of incubation and in 94 metanephric rudiments cultivated as chorioallantoic membrane (CAM) grafts. Then, the morphologic features of renal development were studied in 151 metanephric rudiments subjected to surgical ligation of the primitive ureter and then cultivated as CAM grafts. The ligations were performed with 9-0 silk suture, aided by the operating microscope, and induced before and after the appearance of nephrons. Renal differentiation of the non-ligated rudiments cultivated as CAM grafts resembled that which appeared in situ. Renal differentiation of 87 per cent of nonligated rudiments which survived grafting displayed normal renal development and 13 per cent displayed mild hydronephrosis. Renal differentiation of 67 per cent of the ligated rudiments which survived grafting displayed hydronephrosis and 33 per cent displayed normal development. Dysplasia was never seen in any specimen. Obstruction of the ureter of the developing kidney caused only hydronephrosis in the chick model. It appears that renal dysplasia is not solely caused by simply mechanical obstruction to urinary drainage, even when the obstruction is imposed at early stages of renal development.

The urological evaluation and management of patients with congenital lower urinary tract anomalies prior to renal transplantation

Previously, patients with chronic renal failure and major congenital anomalies of the lower urinary tract (often with urinary diversion) were thought to be poor candidates for renal transplantation. Pre-transplant evaluation and possible urinary reconstruction are essential in these patients to achieve successful renal transplantation. Ten patients, including 7 adults, presented with congenital anomalies of the lower urinary tract that were responsible for renal failure. Percutaneous suprapubic cystostomy aided in the assessment of bladder function. Undiagnosed posterior urethral valves were found in 2 adults. Patients with exstrophy, neurogenic bladder or a contracted bladder (with augmentation cystoplasty) had urinary drainage into the bladder at the time of renal transplantation. Sometimes an imperfect bladder can be used for urinary drainage with transplantation but, otherwise, intestinal conduits are still a viable alternative.