Mechanism of upper tract dilatation in patients with thick walled bladders, chronic retention of urine and associated hydroureteronephrosis

Stratification of neurogenic bladder risk in spina bifida using the urinary peptidome

Neurogenic bladder poses a major morbidity in children with spina bifida (SB), and videourodynamic studies (VUDS) are used to stratify this risk. This small-scale pilot study utilized current mass-spectrometry-based proteomic approaches to identify peptides or proteins in urine that may differentiate children at high risk of developing renal complications from a neurogenic bladder. Twenty-two urine samples of which nine had high bladder pressure storage that put the upper urinary tract at risk, while 13 with a lower risk for renal compromise were analyzed. More than 1,900 peptides across all 22 samples were quantified, and 115 peptides differed significantly (P < 0.05) between the two groups. Using machine learning approaches five peptides that showed the greatest differences between these two clinical categories were used to build a classifier. We tested this classifier by blind analysis of an additional six urine samples and showed that it correctly assigned the unknown samples in their proper risk category. These promising results indicate that a urinary screening test based on peptides could be performed on a regular basis to stratify the neurogenic bladder into low or high-risk categories. Expanding this work to larger cohorts as well as across a broad spectrum of urodynamics outcomes may provide a useful diagnostic test for neurogenic bladder.NEW & NOTEWORTHY This approach could help risk stratify the neurogenic bladder in patients with spina bifida and could allow us to safely defer on up to 1/3 of urodynamic studies. These pilot data justify a larger trial before this approach becomes a clinical tool.

Bladder and Ureteral Dysfunction Leading to Hydronephrosis and Hydroureteronephrosis in Adults

Chronic non-stone-related hydronephrosis from supravesical or bladder dysfunction in adults is often detected incidentally. This study aims to review the literature regarding supravesical obstruction or bladder dysfunction leading to bilateral hydronephrosis in adults and to develop an algorithm to identify patients at risk of renal failure. Cross-sectional studies, retrospective and prospective cohorts, clinical trials, and systematic reviews from 1980 to 2017 were included. From 8115 articles screened, 39 met the inclusion criteria. Despite the lack of studies addressing this issue, this review brings up a rational evidence-based algorithm to diagnose and manage adults with bilateral hydronephrosis due to supravesical or bladder disease or dysfunction.

Posterior urethral valve: Outcome of antenatal intervention

INTRODUCTION AND AIM

Antenatal treatment of obstructive uropathy, although widely performed, remains controversial. This study evaluated the long-term outcome of managing patients with posterior urethral valves (PUV), highlighting the effect of antenatal vesicoamniotic shunt placement for patients who underwent fetal surgery.

METHODS

The medical records of 58 patients with PUV were retrospectively reviewed from June 1998 to June 2004. On the basis of prenatal assessment of sonographic findings and serial urinary electrolytes and protein measurements, patients were divided into two groups: group 1 comprised patients who had antenatal vesicoamniotic shunt placement whereas group 2 comprised patients who underwent postnatal surgical correction of PUV. Their outcomes and long-term results were evaluated.

RESULTS

Patients were followed up from 6 months to 6(1/2) years (mean 3.9 years). Group 1 included 12 patients who had vesicoamniotic shunt placement and were confirmed postnatally to have PUV. Four patients out of 12 died (33.3%); three out of the eight living patients had perinatal complications. Of the eight living patients, three (37.5%) underwent valve ablation and five (62.5%) underwent urinary diversion (three vesicostomies and two cutaneous ureterostomies). Renal function returned to normal in only four patients (50%). Radiological abnormalities (hydronephrosis and/or reflux) resolved in three (37.5%) patients, was downgraded in one (12.5%) patient and persisted in four patients (50%). Group 2 included 46 patients who were treated postnatally. Thirty-five patients (76%) underwent primary valve ablation, while 11 (24%) underwent urinary diversion (seven vesicostomies, four cutaneous ureterostomy and one pyelostomy). Renal function returned to normal in all patients who underwent valve ablation, except in three, while renal function returned to normal in only three of 11 patients who underwent urinary diversion. Radiological hydronephrosis and/or reflux resolved in 28 patients (60.9%), was downgraded in six patients (13%) and persisted in 12 patients (26.1%).

CONCLUSIONS

Antenatal vesicoamniotic shunt placement makes no difference to the outcome and long-term results of patients with PUV and debate about its efficacy on renal outcome remains. Primary valve ablation is the keystone of treatment for patients with PUV that might achieve the primary goal of nephron preservation. The lowest creatinine concentration in the first year of life is the most appropriate predictor of future renal function.

LONG-TERM BLADDER DYSFUNCTION AND RENAL FUNCTION IN BOYS WITH POSTERIOR URETHRAL VALVES BASED ON URODYNAMIC FINDINGS

PURPOSE

Posterior urethral valves are the most common cause of congenital obstructive uropathy leading to renal failure in childhood. We investigate the influence of bladder dysfunction on renal function impairment.

MATERIALS AND METHODS

We retrospectively reviewed the records of 116 patients with posterior urethral valves. After valve ablation urodynamic studies were performed in all patients. The presence of vesicoureteral reflux (VUR), renal dysplasia, serum creatinine during followup as well as urodynamic abnormalities were recorded. Mean followup was 10.3 years after valve ablation.

RESULTS

All patients underwent endoscopic valve ablation and urinary diversion was performed in 32. Renal dysplasia was found in 9 patients. Renal function impairment at the end of followup was present in 35 patients. Urodynamic studies showed poor compliance in 30 boys, detrusor overactivity in 44, and poor compliance and detrusor overactivity in 17. Bilateral VUR was found in 17 boys at the time of diagnosis. Urodynamic studies were normal in 23 (20%) patients, of whom 4 had renal failure. Univariate analysis showed that poor compliance and detrusor overactivity had a significant correlation to renal function impairment in addition to bilateral VUR and renal dysplasia. In a multivariate analysis bilateral VUR was an independent prognostic factor for poor prognosis.

CONCLUSIONS

Bladder dysfunction may contribute to renal function impairment eventually but normal urodynamic findings do not preclude renal deterioration. It is likely that loss of compliance and detrusor overactivity would actually result in a valve bladder reaching its end point function.

Prognostic factors for persistent distal renal tubular acidosis after surgery for posterior urethral valve

Risk factors, including age at presentation, age at surgery, time between presentation and surgery, urodynamic abnormalities, and vesicoureteric reflux, were prospectively studied for the development of distal renal tubular acidosis (DRTA) before surgery and persistent DRTA after surgery in 24 boys with posterior urethral valve (PUV) with normal serum creatinine levels. DRTA was persistent in 11 of 17 boys (65%) at the end of follow-up after intervention. For the development of DRTA before surgery, only a longer time between presentation and surgery (intervening period) turned out to be a significant risk factor on multivariate analysis (beta = -0.13; P = 0.04). Boys with persistent DRTA after surgery had older age at presentation (P = 0.03), older age at surgery (P = 0.001), a longer intervening period (P = 0.0007), and bilateral or severe unilateral reflux (P = 0.04) before surgery. On univariate logistic regression, age at surgery (beta = -0.07; P = 0.04) and intervening period (beta = -0.13; P = 0.02) were found to be significant risk factors for persistent DRTA, but on multivariate analysis, only intervening period was found to be significant (beta = -0.13; P = 0.02). A delay in intervention after noticing voiding symptoms can predict a high incidence of DRTA before intervention and persistent DRTA after surgery in boys with PUV.

Sonographic diagnosis of hydronephrosis in patients with spinal cord injury: influence of bladder fullness

OBJECTIVE

To investigate and compare the diagnostic accuracy of prevoid and postvoid renal sonography in detecting hydronephrosis in patients with spinal cord injury.

STUDY DESIGN

A prospective, blind comparison of renal sonography and excretory urography in 67 spinal cord injury patients who underwent periodic urologic examinations. Renal sonography was performed twice, once when the patient's bladder was physiologically full (prevoid) and again when it was just emptied (postvoid).

RESULTS

Of 140 kidneys, 24 from 16 patients were found to have hydronephrosis by excretory urography; 116 kidneys had normal urogram findings. Prevoid sonography missed the diagnosis of hydronephrosis in one kidney and showed hydronephrosis in 18 kidneys that had normal results on excretory urography (sensitivity, 95.8%; specificity, 84.5%; negative predictive value, 99.0%). The postvoid sonograms did not detect hydronephrosis in four kidneys and showed hydronephrosis in six kidneys that had normal results on excretory urography (sensitivity, 83.3%; specificity, 94.8%; negative predictive value, 96.5%). Compared to excretory urography, renal sonography detected eight more upper urinary tract abnormalities, which were confirmed by cystograms or radioisotopic renograms.

CONCLUSION

Performing renal sonography while the bladder is full can increase the sensitivity in detecting hydronephrosis in asymptomatic spinal cord injured patients.

The predictive value of ultrasonography in evaluation of infants with posterior urethral valves

Between 1981 and 1989, 28 infants less than 6 months old with posterior urethral valves underwent ultrasound evaluation as part of the initial evaluation at our hospital. The single ultrasound feature that correlated with subsequent renal function was the status of corticomedullary differentiation. The presence of corticomedullary junctions in at least 1 kidney in 17 infants was always associated with a serum creatinine level of 0.8 mg./dl. or less in long-term followup. Of 11 patients with absent corticomedullary differentiation 7 had eventual creatinine levels of greater than 0.8 mg./dl. with 5 of them suffering clinically significant renal insufficiency. An association between vesicoureteral reflux and absent corticomedullary junctions was also found.

Bladder pressure and kidney function in children with myelomeningocoele: review article

Therapy of children with myelomeningocoele should achieve a double goal: on the one hand, obtain continence and, on the other hand, preserve kidney function without complications. The first goal is a social and psychological one, the latter is a vital one.

Cystoplasty: tubularisation or detubularisation?

Previous studies on substitution or augmentation cystoplasty have highlighted the profusion of surgical techniques available, but there is disagreement as to which is the best. We established an animal model to compare various types of cystoplasties, tubularised and detubularised, using ileum and caecum. Detubularisation did not abolish intrinsic bowel contractions but delayed their onset. No differences were noted in the frequency and amplitude of such contractions after detubularisation or between large and small bowel cystoplasties. Although intravenous urography did not demonstrate any abnormality in upper tract anatomy, a significant number of animals had some functional disturbance of the kidney after cystoplasty demonstrable on isotope renography, irrespective of the surgical technique. It may be possible to prevent these contractions with their associated harmful effects by preventing the bladder volume from building up excessively.

Effect of bladder filling on upper tract urodynamics in man

A group of 21 patients with hydronephrosis but normal bladders had their upper urinary tract pressures monitored while perfusing the affected kidneys through a fine bore nephrostomy tube, initially with the bladder on free drainage and subsequently during bladder filling. In 7 patients the renal pelvic pressures were altered by bladder filling and loin pain was reproduced in 4. It was concluded that with high upper tract flow rates, vesical filling can affect upper tract dynamics and this should be considered when evaluating patients with loin pain or potential obstructive uropathy.