Linear growth after enterocystoplasty in children and adolescents: a review

Posterior urethral valves: Role of prenatal diagnosis and long-term management of bladder function; a single center point of view and review of literature

Posterior Urethral Valves (PUV) are the most common cause of lower urinary tract obstruction. More severe forms are detected early in pregnancy (mainly type I), while other forms are usually discovered later in childhood when investigating lower urinary tract symptoms. Bladder dysfunction is common and is associated with urinary incontinence in about 55% (0%-72%). Despite the removal of the obstruction by urethral valve ablation, pathological changes of the urinary tract can occur with progressive bladder dysfunction, which can cause deterioration of the upper urinary tract as well. For this reason, all children with PUV require long-term follow-up, always until puberty, and in many cases life-long. Therefore, management of PUV is not only limited to obstruction relief, but prevention and treatment of bladder dysfunction, based on urodynamic observations, is paramount. During time, urodynamic patterns may change from detrusor overactivity to decreased compliance/small capacity bladder, to myogenic failure (valve bladder). In the past, an aggressive surgical approach was performed in all patients, and valve resection was considered an emergency procedure. With the development of fetal surgery, vesico-amniotic shunting has been performed as well. Due to improvements of prenatal ultrasound, the presence of PUV is usually already suspected during pregnancy, and subsequent treatment should be performed in high-volume centers, with a multidisciplinary, more conservative approach. This is considered to be more effective and safer. Primary valve ablation is performed after clinical stability and is no longer considered an emergency procedure after birth. During childhood, a multidisciplinary approach (pediatric urologist, nephrologist, urotherapist) is recommended as well in all patients, to improve toilet training, using an advanced urotherapy program with medical treatments and urodynamic evaluations. The aim of this paper is to present our single center experience over 30 years.

Neuropathic Bladder and Augmentation Cystoplasty

Surgical indications for individuals with neuropathic bladder include unsafe urinary storage pressures, progressive upper tract deterioration, and continued urinary incontinence that is recalcitrant to oral pharmacologic or intradetrusor injection therapy and intermittent catheterization. Bladder augmentation is currently the gold standard surgical procedure used to increase bladder capacity and reduce storage pressures but has significant long-term risks. The medical and surgical management of neuropathic bladder, as well as long-term consequences of bladder augmentation, are reviewed.

Effect of gastrocystoplasty on height and bone density in children

Introduction:

Gastrointestinal tissue in the urinary tract results in numerous metabolic changes. This study investigates the effects of augmentation gastrocystoplasty on the height and bone mineralization in bladder exstrophy patients.

Aim and Objective:

To analyze the long-term outcome following gastrocystoplasty in terms of height, bone mineral density, acid base changes, and complications.

Materials and Methods:

Cross-sectional study was done after obtaining institutional ethics committee clearance. Inclusion criteria included retrospective analysis of all cases who had undergone gastrocystoplasty since 1992 and prospective analysis of all cases who are undergoing gastrocystoplasty during the study period from June 2008 to December 2010. Exclusion criteria included follow up period of less than 2 years and cases lost to follow up. Indian standard charts were used for anthropometric measurement, and bone density scan of lumbar vertebrae and upper end of femur were done for bone matrix and mineral density.

Results:

A total of 23 patients were included in the study. Out of 23 patients, 16 were males and 7 were females. Mean age at gastrocystoplasty was 8.28 years, and mean follow up period was 60 months. The median pre-augmentation and post-augmentation percentile height and weight were 56, 59 and 59, 61 respectively. Mean bone density value was 0.654.

Conclusion:

Augmentation gastrocystoplasty is a safe and viable option without any adverse effect on height or bone mineral density without altering metabolic or acid base homeostasis.

Enterocystoplasty: The long-term effects on bone mineral density

BACKGROUND

Studies show that enterocystoplasty has a negative effect on bone mineral density (BMD). The aim of this study was to investigate the long-term impact of enterocystoplasty on BMD. We used dual energy x-ray absorptiometry (DEXA) scans to determine BMD and identify patients with osteopenia and osteoporosis who are at potential long-term risk for fracture.

MATERIALS AND METHODS

We reviewed our database of >200 individuals, who had undergone enterocystoplasty or continent diversion for both neurogenic and non-neurogenic reasons during childhood. We chose to study the non-neurogenic group first for a number of technical reasons, and identified 24 individuals who had undergone the procedure for non-neurogenic reasons, and had more than 15 years of follow-up. In addition we had a control group of 10 individuals born with bladder exstrophy, who had undergone primary closure before the year 2000, without enterocystoplasty. We used DEXA scan T- and Z-scores to identify patients with osteopenia and osteoporosis.

RESULTS

Eleven of 24 patients had normal DEXA scans with normal T- and Z-scores; seven had identifiable osteopenia and increased long-term risk for fracture. Six had osteoporosis; three of whom had reduced glomerular filtration rate (GFR). Eight of the 10 individuals in the control group had a normal DEXA scan.

CONCLUSIONS

Enterocystoplasty during childhood can lead to loss of BMD. This does not seem to be related to the enterocystoplasty alone. It is more pronounced in individuals who have other risk factors, such as reduced GFR. The identification of BMD loss makes it possible to intervene before osteoporosis occurs and leads to pathologic fracture.

British Association of Paediatric Urologists consensus statement on the management of the neuropathic bladder

INTRODUCTION

A large number of children with spina bifida develop a neuropathic bladder and this group of patients still forms the largest group of children who require urological management. Although there are published guidelines on the management of the neuropathic bladder, they are not specific to children. It is unsurprising, therefore, that the initial investigation, assessment and management of children with spina bifida vary considerably. The 2014 British Association of Paediatric Urologists (BAPU) meeting was devoted to the management of the neuropathic bladder. The aim was to produce a consensus on the appropriate investigation and management of a child with a neuropathic bladder.

METHODS AND MATERIALS

A questionnaire was devised and the members were polled on their current practice. Six paediatric urology fellows presented an evidence-based literature review on different aspects of the neuropathic bladder. At the end of the session, the members of the organisation present were polled again using the same questions.

RESULTS

The BAPU felt that the use of urodynamics in the neuropathic bladder should be selectively determined by clinical parameters. Regarding CIC, the group was evenly split between universal use or only when poor emptying was established. Oxybutinin was the first-line anticholinergic of choice. Most paediatric urologists routinely used Botox and were happy to use it repeatedly. The surgical intervention most frequently employed was determined to be an ileocystoplasty, with most surgeons deferring the need for surveillance cystoscopy until at least 10 years after surgery.

CONCLUSION

It was felt that a consensus statement is not a guideline or a way to establish best practice; however, it serves as a way of surveying current practice and providing a benchmark for clinicians involved in the management of these patients.

Anthropometric measurements as an indicator of nutritional status in spina bifida patients undergoing enterocystoplasty

OBJECTIVE

To use anthropometric measurements to compare nutritional status in children with neurogenic bladder dysfunction secondary to meningomyelocele who underwent enterocystoplasty and those who did not undergo surgery.

METHODS

A case-control study was conducted in 20 children, divided into two groups: those who had enterocystoplasty (Group A) and those who did not undergo surgery (Group B), matched for genre and age. Weight, height, arm circumference, and triceps skinfold thickness were the parameters used. Nutritional assessment was determined by calculating the indexes, based on age and genre. Classification was based on the percentile and the results were compared with the reference values.

RESULTS

The mean age was 6.41 years in Group A and 6.35 years in Group B. The interval between surgery and evaluation was 11 months. The following measures were found for Group A: 80% of children were eutrophic, a percentage 30% greater than that in Group B; arm muscle circumference was adequate in 40% of patients, a percentage 20% greater than that in Group B; arm muscle area was adequate in 90%, a percentage 30% greater than that in Group B. Values in Group B were as follows: for triceps skinfold thickness, 60% of patients had values above the mean, a percentage 20% greater than that in Group A; for arm fat index, 60% of patients were above the mean value, 40% greater than in Group A.

CONCLUSION

Patients who had undergone enterocystoplasty showed better nutritional status, while the control group presented higher fat indexes in anthropometric measures. However, the differences between groups were not statistically significant.

Ileal bladder augmentation and vitamin B12: levels decrease with time after surgery

OBJECTIVE

We investigated vitamin B12 deficiency following ileocystoplasty in children.

METHODS

Patients who underwent ileocystoplasty between December 1993 and September 2006 were included and B12 levels were retrospectively analysed. Patients with a serum B12 of less than 150 pg/ml were considered deficient. The distance of the ileal segment from the ileocaecal valve was recorded.

RESULTS

There were 105 patients in the series; 61 were male. Mean age at surgery was 7.7 years (SD = 3.9). The mean interval from surgery to most recent B12 level was 50 months (SD = 30). None of the patients were on B12 supplementation. Two patients were B12 deficient, both more than 7 years after surgery; 44% of patients with levels available 7 years after surgery had a B12 below 300 pg/ml. There was a significant negative correlation between B12 level and length of follow up (Spearman's rank, P < 0.01). Twenty patients with an ileal segment sparing 60 cm from the ileocaecal valve had a higher mean B12 (524 vs 419, SEM 60 vs 28). This was not statistically significant.

CONCLUSION

We demonstrate a reduction in serum B12 level with time following ileocystoplasty. These patients should have their B12 levels measured in the long term.

Exstrophy bladder: Effect of sigmoid colocystoplasty on physical growth and bone mineral density

Background and Aims:

Introduction of intestinal tissue in the urinary tract results in numerous metabolic changes. This study investigates the effects of augmentation sigmoid colocystoplasty on the physical growth and bone mineralization in bladder exstrophy patients.

Materials and Methods:

Physical growth, serum biochemistry and bone mineral density were assessed pre and post augmentation in 34 of 54 patients who were treated by staged sigmoid colocystoplasty for classical bladder exstrophy during the period 1985–2007. Physical growth was determined by comparing the height and weight for age with standard growth charts. Serum biochemistry included calcium, phosphate and alkaline phosphatase levels. Bone mineral density (BMD) was determined at the femoral head using the dual energy X-ray absorptiometry (DEXA) scan at 15 ± 4.5 months after the augmentation. The DEXA scan findings were compared with 22 normal Indian children who served as controls and 18 unaugmented patients with bladder exstrophy. In 13 augmented patients, the DEXA scan could be repeated after an interval of six months.

Results:

The mean percentile height and weight were comparable in the pre and post-augmentation period with no statistically significant difference (P=0.135 for height and P=0.232 for weight). Biochemical parameters of bone metabolism also did not show any statistically significant changes after colocystoplasty. The BMD was 0.665 ± 0.062 g/cm² in the controls and 0.612 ± 0.10 g/cm² in the unaugmented bladder exstrophy patients. In the augmented patients, the BMD was 0.645 ± 0.175 g/cm² and six months later it was 0.657 ± 0.158 g/cm². These differences were not statistically significant.

Conclusions:

In our study, no significant effects on the physical growth and bone mineral metabolism were observed in exstrophy bladder patients following sigmoid colocystoplasty.

Continent urinary diversion in the epispadias-exstrophy complex

Despite improvements in modern surgical reconstructive techniques, many patients with epispadias-exstrophy continue to experience urinary incontinence. Continent diversion is commonly performed to achieve urinary continence and improve quality of life. In this work we describe the population that can be considered for continent urinary diversion, consider the benefits and implications of concurrent augmentation and bladder neck closure, and review recent literature regarding continence outcomes and common complications. Even in this complex patient population, urinary continence can be reliably achieved by bladder augmentation and the use of intermittent catheterization via a catheterizable cutaneous stoma with or without closure of the bladder neck.

Meningomylocele: An update

Therapy-resistant overactivity of detrusor or small capacity and poor compliance, will usually need to be treated by bladder augmentation. Ileal or colonic patches are used frequently for augmenting the bladder, with either intestinal segment appearing to be equally useful. Stomach is rarely used because of the associated complications, but it is the only available intestinal segment for patients with impaired renal function. Concerns regarding long-term effects of associated metabolic acidosis, including abnormalities in linear growth and bone metabolism are misplaced. Ureterocystoplasty offers an attractive urothelium-preserving alternative, avoiding the metabolic complications, mucus production and cancer risk of heterotopic epithelium associated with enterocystoplasty. Though ideal for patients with dilated ureter and nonfunctioning kidney, in patients with functioning kidney it carries added risks associated with transuretero-ureterostomy, mainly obstruction. Ureteral dilatation in meningomyelocele patients is avoidable with proper follow-up and treatment. Therefore they rarely should be candidates for this operation. Alternative urothelium-preserving techniques, such as auto augmentation and seromuscular cystoplasty, have not proven to be as successful as standard augmentation with intestinal segment. Work is in progress on various bioengineering techniques to culture and combine bladder cells in tissue culture for regeneration. Early efforts are exciting, but preliminary.

Osteoporosis in children and adolescents: etiology and management

Bone mass increases progressively during childhood, but mainly during adolescence when approximately 40% of total bone mass is accumulated. Peak bone mass is reached in late adolescence, and is a well recognised risk factor for osteoporosis later in life. Thus, increasing peak bone mass can prevent osteoporosis. The critical interpretation of bone mass measurements is a crucial factor for the diagnosis of osteopenia/osteoporosis in children and adolescents. To date, there are insufficient data to formally define osteopenia/osteoporosis in this patient group, and the guidelines used for adult patients are not applicable. In males and females aged <20 years the terminology 'low bone density for chronologic age' may be used if the Z-score is less than -2. For children and adolescents, this terminology is more appropriate than osteopenia/osteoporosis. Moreover, the T-score should not be used in children and adolescents. Many disorders, by various mechanisms, may affect the acquisition of bone mass during childhood and adolescence. Indeed, the number of disorders that have been identified as affecting bone mass in this age group is increasing as a consequence of the wide use of bone mass measurements. The increased survival of children and adolescents with chronic diseases or malignancies, as well as the use of some treatment regimens has resulted in an increase in the incidence of reduced bone mass in this age group. Experience in treating the various disorders associated with osteoporosis in childhood is limited at present. The first approach to osteoporosis management in children and adolescents should be aimed at treating the underlying disease. The use of bisphosphonates in children and adolescents with osteoporosis is increasing and their positive effect in improving bone mineral density is encouraging. Osteoporosis prevention is a key factor and it should begin in childhood. Pediatricians should have a fundamental role in the prevention of osteoporosis, suggesting strategies to achieve an optimal peak bone mass.