The effect of dysfunctional voiding on the costs of treating vesicoureteral reflux: a computer model

Quality assessment of economic evaluation studies in pediatric surgery: a systematic review

PURPOSE

To assess economic evaluation studies (EES) in pediatric surgery and to identify potential factors associated with high-quality studies.

METHODS

A systematic review of the literature using PubMed and Cochrane databases was conducted to identify EES in pediatric surgery published between 1 June 1993 and 30 June 2013. Assessment criteria are derived from the Drummond checklist. A high quality study was defined as a Drummond score ≥7. Logistic regression analysis was used to determine factors associated with high quality studies.

RESULTS

119 studies were included. 43.7% (n=52) of studies were full EES. Cost-effectiveness analysis was the most frequent (61.5%) type of full EES. Only 31.6% of studies had a Drummond score ≥7 and 73% of these were full EES. The factors associated with high quality were identification of costs (OR: 14.08; 95% CI: 3.38-100; p<0.001), estimation of utility value (OR: 8.13; 95% CI: 2.02-43.47; p=0.005) and study funding (OR: 3.50; 95% CI: 1.27-10.10; p=0.02).

CONCLUSION

This review shows that the number and the quality of EES are low despite the increasing number of studies published in recent years. In the current context of budget constraints, our results should encourage pediatric surgeons to focus more on EES.

Social stress in mice induces voiding dysfunction and bladder wall remodeling

Several studies have anecdotally reported the occurrence of altered urinary voiding patterns in rodents exposed to social stress. A recent study characterized the urodynamic and central changes in a rat model of social defeat. Here, we describe a similar voiding phenotype induced in mice by social stress and in addition we describe potential molecular mechanisms underlying the resulting bladder wall remodeling. The mechanism leading to the altered voiding habits and underlying bladder phenotype may be relevant to the human syndrome of dysfunctional voiding which is thought to have a psychological component. To better characterize and investigate social stress-induced bladder wall hypertrophy, FVB mice (6 wk old) were randomized to either social stress or control manipulation. The stress involved repeated cycles of a 1-h direct exposure to a larger aggressive C57Bl6 breeder mouse followed by a 23-h period of barrier separation over 4 wk. Social stress resulted in altered urinary voiding patterns suggestive of urinary retention and increased bladder mass. In vivo cystometry revealed an increased volume at micturition with no change in the voiding pressure. Examination of these bladders revealed increased nuclear expression of the transcription factors MEF-2 and NFAT, as well as increased expression of the myosin heavy chain B isoform mRNA. BrdU uptake was increased within the urothelium and lamina propria layers in the social stress group. We conclude that social stress induces urinary retention that ultimately leads to shifts in transcription factors, alterations in myosin heavy chain isoform expression, and increases in DNA synthesis that mediate bladder wall remodeling. Social stress-induced bladder dysfunction in rodents may provide insight into the underlying mechanisms and potential treatment of dysfunctional voiding in humans.

Diagnosis and management of urinary incontinence and functional fecal incontinence (encopresis) in children

The ability to maintain normal continence for urine and stools is not achievable in all children by a certain age. Gaining control of urinary and fecal continence is a complex process, and not all steps and factors involved are fully understood. While normal development of anatomy and physiology are prerequisites to becoming fully continent, anatomic abnormalities, such as bladder exstrophy, epispadias, ectopic ureters, and neurogenic disturbances that can usually be recognized at birth and cause incontinence, will require specialist treatment, not only to restore continence but also to preserve renal function. Most forms of urinary incontinence are not caused by an anatomic or physiologic abnormality and, hence, are more difficult to diagnose and their management requires a sound knowledge of bladder and bowel function.

The Cost-Effectiveness of Dextranomer/Hyaluronic Acid Copolymer for the Management of Vesicoureteral Reflux. 2. Reflux Correction at the Time of Diagnosis as a Substitute for Traditional Management

PURPOSE

The use of dextranomer/hyaluronic acid copolymer has become increasingly popular as an alternative to ureteral reimplantation in the treatment of vesicoureteral reflux. We compared the cost-effectiveness of performing dextranomer/hyaluronic acid injection at the time of diagnosis of reflux to that of traditional management.

MATERIALS AND METHODS

A model to estimate the costs of managing vesicoureteral reflux has previously been created. We updated the model to compare the costs of managing vesicoureteral reflux by traditional methods with the costs of managing reflux if dextranomer/hyaluronic acid injection is performed at the time of diagnosis. The success rate required for dextranomer/hyaluronic acid injection at diagnosis to be as cost effective as traditional management was estimated. We used 2 models of dextranomer/hyaluronic acid injection at diagnosis-injection at diagnosis proceeding to traditional management if injection failed (scenario 1), and injection at diagnosis proceeding to ureteral reimplantation if injection failed (scenario 2).

RESULTS

If reflux is stratified by grade in scenario 1, for grades III, IV and V respective success rates of 88.5%, 66.6%, and 55.6% for unilateral reflux and 97.5%, 89.7% and 91.4% for bilateral reflux must be achieved to have equal cost-effectiveness to traditional management, while grades I and II reflux can never achieve equal cost-effectiveness. Stratified by grade for scenario 2, for grades III, IV and V respective success rates of 86.9%, 70.8% and 55.8% for unilateral reflux, and 97.6%, 89.8% and 89.8% for bilateral reflux must be achieved to attain equal cost-effectiveness compared to traditional management. In scenario 2 dextranomer/hyaluronic acid injection at diagnosis for grades I and II unilateral and bilateral reflux can never achieve equal cost-effectiveness compared to traditional management.

CONCLUSIONS

Based on the results of this study, in most clinical situations dextranomer/hyaluronic acid injection at the time of diagnosis is unlikely to be as cost effective as traditional management of vesicoureteral reflux.

The cost-effectiveness of dextranomer/hyaluronic acid copolymer for the management of vesicoureteral reflux. 1: substitution for surgical management

PURPOSE

We examined the cost-effectiveness of dextranomer/hyaluronic acid copolymer injection in patients who would otherwise undergo ureteral reimplantation.

MATERIALS AND METHODS

A model for managing vesicoureteral reflux has previously been created. We now update the model to compare the costs of treating vesicoureteral reflux using standard methods (ie ureteral reimplantation after failed medical therapy) with the costs of dextranomer/hyaluronic acid injection.

RESULTS

In the first scenario created dextranomer/hyaluronic acid injection is substituted for ureteral reimplantation when surgical intervention would be performed for treatment of breakthrough infection or failure of the reflux to resolve. For dextranomer/hyaluronic acid injection to have equal cost-effectiveness compared to ureteral reimplantation in this scenario success rates for dextranomer/hyaluronic acid injection would need to be 57.8% per ureter for patients with unilateral reflux and 75.3% per ureter for patients with bilateral reflux. However, if increasing grades of reflux require increasing volumes of dextranomer/hyaluronic acid, success rates would need to be 72.5% for patients with unilateral reflux and 93.8% for patients with bilateral reflux. In the second scenario created dextranomer/hyaluronic acid injection is repeated if it fails to resolve the reflux after the first injection. Success rates to obtain equal cost-effectiveness for the repeat dextranomer/hyaluronic acid injection would need to be 0%, 11.4% and 60.3% in patients with unilateral reflux if the respective success rates of the initial injection were 85%, 70% and 55%. Success rates for the second dextranomer/hyaluronic acid injection would need to be 0%, 29.1% and 76.7% per ureter in patients with bilateral reflux if the respective success rates of the initial injection were 85%, 70% and 55%. If increasing volumes of dextranomer/hyaluronic acid were required for increasing grades of reflux, a second dextranomer/hyaluronic acid injection would not be a viable option.

CONCLUSIONS

Based on our results, dextranomer/hyaluronic acid injection may be more cost-effective than ureteral reimplantation for children who meet standard criteria for surgical therapy, especially for lower grades of reflux. If increasing grades of reflux require an increased volume of dextranomer/hyaluronic acid, then injection would likely be cost-effective only for grades I and II unilateral and bilateral reflux, and perhaps unilateral grade III reflux.

Voiding dysfunction in children

The practicing urologist commonly sees children with lower-urinary tract dysfunction who wet or have recurrent urinary tract infections. This article identifies the proposed etiologies of such behavior in children in whom there are no anatomic or neuropathic causes, outlines the approach to evaluating affected children, and describes a stepwise,interdisciplinary approach to treatment.