Estimating normal bladder capacity in children

Characterization of pediatric urinary microbiome at species-level resolution indicates variation due to sex, age, and urologic history

BACKGROUND

Recently, associations between recurrent urinary tract infections (UTI) and the urinary microbiome (urobiome) composition have been identified in adults. However, little is known about the urobiome in children. We aimed to characterize the urobiome of children with species-level resolution and to identify associations based on UTI history.

STUDY DESIGN

Fifty-four children (31 females and 21 males) from 3 months to 11 years of age participated in the study. Catheterized urine specimens were obtained from children undergoing a clinically indicated voiding cystourethrogram. To improve the analysis of the pediatric urobiome, we used a novel protocol using filters to collect biomass from the urine coupled with synthetic long-read 16S rRNA gene sequencing to obtain culture-independent species-level resolution data. We tested for differences in microbial composition between sex and history of UTIs using non-parametric tests on individual bacteria and alpha diversity measures.

RESULTS

We detected bacteria in 61% of samples from 54 children (mean age 40.7 months, 57% females). Similar to adults, urobiomes were distinct across individuals and varied by sex. The urobiome of females showed higher diversity as measured by the inverse Simpson and Shannon indices but not the Pielou evenness index or number of observed species (p = 0.05, p = 0.04, p = 0.35, and p = 0.11, respectively). Additionally, several species were significantly overrepresented in females compared to males, including those from the genera Anaerococcus, Prevotella, and Schaalia (p = 0.03, 0.04, and 0.02, respectively). Urobiome diversity increased with age, driven mainly by males. Comparison of children with a history of 1, 2, or 3+ UTIs revealed that urobiome diversity significantly decreases in the group that experienced 3+ UTIs as measured by the Simpson, Shannon, and Pielou indices (p = 0.03, p = 0.05, p = 0.01). Several bacteria were also found to be reduced in abundance.

DISCUSSION

In this study, we confirm that urobiome can be identified from catheter-collected urine specimens in infants as young as 3 months, providing further evidence that the pediatric bladder is not sterile. In addition to confirming variations in the urobiome related to sex, we identify age-related changes in children under 5 years of age, which conflicts with some prior research. We additionally identify associations with a history of UTIs.

CONCLUSIONS

Our study provides additional evidence that the pediatric urobiome exists. The bacteria in the bladder of children appear to be affected by early urologic events and warrants future research.

Characterization of pediatric urinary microbiome at species-level resolution indicates variation due to sex, age, and urologic history

Background

Recently, associations between recurrent urinary tract infections (UTI) and the urinary microbiome (urobiome) composition have been identified in adults. However, little is known about the urobiome in children. We aimed to characterize the urobiome of children with species-level resolution and to identify associations based on UTI history.

Study design

Fifty-four children (31 females and 21 males) from 3 months to 5 years of age participated in the study. Catheterized urine specimens were obtained from children undergoing a clinically indicated voiding cystourethrogram. To improve the analysis of the pediatric urobiome, we used a novel protocol using filters to collect biomass from the urine coupled with synthetic long-read 16S rRNA gene sequencing to obtain culture-independent species-level resolution data. We tested for differences in microbial composition between sex and history of UTIs using non-parametric tests on individual bacteria and alpha diversity measures.

Results

We detected bacteria in 61% of samples from 54 children (mean age 40.7 months, 57% females). Similar to adults, urobiomes were distinct across individuals and varied by sex. The urobiome of females showed higher diversity as measured by the inverse Simpson and Shannon indices but not the Pielou evenness index or number of observed species (p = 0.05, p=0.04, p = 0.35, and p = 0.11, respectively). Additionally, several species were significantly overrepresented in females compared to males, including those from the genera Anaerococcus, Prevotella, and Schaalia (p = 0.03, 0.04, and 0.02, respectively). Urobiome diversity increased with age, driven mainly by males. Comparison of children with a history of 1, 2, or 3+ UTIs revealed that urobiome diversity significantly decreases in the group that experienced 3+ UTIs as measured by the Simpson, Shannon, and Pielou indices (p = 0.03, p = 0.05, p = 0.01). Several bacteria were also found to be reduced in abundance.

Discussion

In this study, we confirm that urobiome can be identified from catheter-collected urine specimens in infants as young as 3 months, providing further evidence that the pediatric bladder is not sterile. In addition to confirming variations in the urobiome related to sex, we identify age-related changes in children under 5 years of age, which conflicts with some prior research. We additionally identify associations with a history of UTIs.

Conclusions

Our study provides additional evidence that the pediatric urobiome exists. The bacteria in the bladder of children appear to be affected by early urologic events and warrants future research.

Bladder capacity in an elimination communication infant: a case report

BACKGROUND

Bladder capacity is essential in assessing children with voiding dysfunction, yet it is currently unclear how best to determine a benchmark bladder capacity; various formulas have been proposed.

CASE PRESENTATION

This report details the unique case of an elimination communication Caucasian infant (< 2 years old) who achieved nighttime and daytime dryness by 6 months of age. His first morning voids were measured from 8 to 20 months of age and compared with three formulas: (1) the Koff formula, a widely used formula based on fill volumes in anesthetized infants; (2) the Kaefer formula, a formula based on fill volume in nonanesthetized infants; and (3) the Holmdahl formula, a formula based on frequency-volume charts in normal infants.

CONCLUSION

This infant's first morning void was found to be most consistent with Kaefer's formula. Further research is required to determine if formulas based on fill volume in nonanesthetized infants provide the more accurate benchmark bladder capacity in infants.

Bladder capacity and growth in classic bladder exstrophy: A novel predictive tool

INTRODUCTION

Bladder capacity (BC) is an important metric in the management of patients with classic bladder exstrophy (CBE). BC is frequently used to determine eligibility for surgical continence procedures, such as bladder neck reconstruction (BNR), and is associated with the likelihood of achieving urinary continence.

OBJECTIVE

To use readily available parameters to develop a nomogram that could be used by patients and pediatric urologists to predict BC in patients with CBE.

STUDY DESIGN

An institutional database of CBE patients was reviewed for those who have undergone annual gravity cystogram 6 months after bladder closure. Candidate clinical predictors were used to model BC. Linear mixed effects models with random intercept and slope were used to construct models predicting log transformed BC and were compared with adjusted R2, Akaike Information Criterion (AIC), and cross-validated mean square error (MSE). Final model evaluated via K-fold cross-validation. Analyses were performed using R version 3.5.3 and the prediction tool was developed with ShinyR.

RESULTS

In total, 369 patients (107 female, 262 male) with CBE had at least one BC measurement after bladder closure. Patients had a median of 3 annual measurements (range 1-10). The final nomogram includes outcome of primary closure, sex, log-transformed age at successful closure, time from successful closure, and interaction between outcome of primary closure and log-transformed age at successful closure as the fixed effects with random effect for patient and random slope for time since successful closure (Extended Summary).

DISCUSSION

Using readily accessible patient and disease related information, the bladder capacity nomogram in this study provides a more accurate prediction of bladder capacity ahead of continence procedures when compared to the age-based Koff equation estimates. A multi-center study using this web-based CBE bladder growth nomogram (https://exstrophybladdergrowth.shinyapps.io/be_app/) will be needed for widespread application.

CONCLUSION

Bladder capacity in those with CBE, while known to be influenced by a broad swath of intrinsic and extrinsic factors, may be modeled by the sex, outcome of primary bladder closure, age at successful bladder closure and age at evaluation.

Can we predict urethral length of boys? - An observational study

INTRODUCTION

An additional knowledge about normal anatomy of urethra in boys can improve clinical outcome of any urological interventions. This will also reduce catheter related complications like intra vesical knotting and urethral injuries. At present there is no systematic data available which has studied the urethral length of boys. We have done this study to analyse the length of urethra in boys.

AIM

The aim of the study is to measure the urethral length in Indian children from the age of 1 year till 15 years and plot a nomogram. Furthermore to analyse the influence of anthropometry on urethral length and derived a formula to predict the urethral length in boys.

STUDY DESIGN

This is a single institution prospective observational study. After obtaining clearance from the institutional review board, a total of 180 children from the age of 1-15 were recruited for the study. The urethral length was measured during Foley's catheter removal. Other data like age, weight, and height of the patient are collected and the obtained values were analysed with SPSS software. The acquired figures were further used to derive formulae to predict urethral length.

RESULTS

A nomogram of urethral length based on age was plotted. With collected figures, five separate formulae were derived to calculate the urethral length based on the age, height and weight. Furthermore for day-to-day use we have deduced a formulas to calculate urethral length which are simplified forms of original formulae.

DISCUSSION

The length of urethra of a new-born male is 5 cm, which attains 8 cm by three years of age and to 17 cm by adulthood. There were attempts to measure the urethral length in adults using cystoscopy, Foley's catheter and different imaging techniques like Magnetic Resonance Imaging and dynamic retrograde urethrography. Simplified formulae which has been derived from this study for clinical use is Urethral length = 8.7 + Age (in year) × 0.55 CONCLUSION: Our results will complement the current anatomical understanding of the urethra. This evades some rare complications of catheterisation and facilitate reconstructive procedures.

A Study of Urodynamic Parameters at Different Bladder Filling Stages for Predicting Upper Urinary Tract Dilatation

Purpose

To identify more accurate predictors of upper urinary tract dilatation (UUTD) in neurogenic bladder (NB) children, we studied the relationship among urodynamic parameters at different bladder filling stages, detrusor leak point pressure (DLPP) and UUTD.

Methods

A total of 158 children (3–16 years) with NB were included and then divided into 2 groups according to whether their NB diagnosis was complicated with UUTD: the UUTD group (39 patients) and those without UUTD group (control group, 119 patients). The bladder filling phase was divided into 3 equal parts: the early, middle, and end filling stages. The bladder compliance (BC) and detrusor pressure (△P_det) at each phase and DLPP at the end filling stage were recorded.

Results

A BC<8 mL/cm H₂O both in the middle and end stages is more specific than a BC<9 mL/cm H₂O in the end stage (72%, 73%, vs. 66%), and △P_det >8 cm H₂O in the early stage, 20 cm H₂O in the middle stage and 25 cm H₂O in the end stage are more sensitive than △P_det >40 cm H₂O in the end stage (82%, 85%, 85%, vs. 49%). A DLPP cutoff value of 20 cm H₂O showed higher sensitivity for predicting UUTD than 40 cm H₂O.

Conclusions

Low BC and a high △P_det in the middle and end filling stages are more accurate factors than classic indicators for predicting UUTD. In addition, a DLPP value of >20 cm H₂O in the end bladder filling stage shows high sensitivity.

Can ultrasound measurement of bladder wall thickness be a useful adjunct for regular urodynamics in children with spina bifida?

INTRODUCTION

Spina bifida is a major cause of neurologic bladder dysfunction among children. The goal of neurogenic bladder treatment is to preserve renal function. Close follow-up is essential, as lower urinary tract functions can change with patient growth. Presently, invasive urodynamics is the gold standard for precisely assessing lower urinary tract function. Ultrasound is a low-cost, non-invasive, uncomplicated examination that can be easily repeated. Bladder wall thickness (BWT) measurement by ultrasound has been proposed as a non-invasive alternative for identifying lower urinary tract dysfunctions.

OBJECTIVE

Currently there are few reports on BWT in children with spina bifida, and BWT assessment methodology has yet to be defined. The present study aim was to investigate whether BWT could be a useful adjunct for regular urodynamics in children with spina bifida. We especially focused on the precise bladder volume during BWT measurements that were simultaneously performed with urodynamics.

STUDY DESIGN

This prospective observational study investigated 33 patients with spina bifida who underwent video urodynamics. We assessed BWT measurements using ultrasound simultaneously performed with video urodynamics. BWT was calculated for the ventral and dorsal walls at 0%, 20%, 40%, 60%, 80%, and 100% of the expected bladder capacity.

RESULTS

Median of bladder capacity was 240 mL, and bladder compliance was 19.2 mL/cmH₂O. Detrusor overactivity was present in 66.7% and vesicoureteral reflux was present in 27.3% of the patients. BWT of the ventral wall was significantly lower than the dorsal wall. During increases in the bladder volume, both the ventral and dorsal walls exhibited proportional thinning (p < 0.05). There were no significant differences for BWT between males and females. Although there was a higher statistical tendency for detrusor overactivity versus without detrusor overactivity (p = 0.085), there were no significant differences found between patients with and without detrusor overactivity.

DISCUSSION

This is the first report where multiple BWT measurements points with video urodynamics were simultaneously performed. Selection of bladder volumes for BWT measurements is critical. Our current study measured six points for each patient during urodynamics. However, available data was not sufficient for detecting bladder function. Until now, there has been no valid standard condition defined for measuring BWT and thus, lack of a standardized method has resulted in discrepancies among studies.

CONCLUSION

Our measurement conditions showed BWT may not correlate with the degree of bladder detrusor dysfunction. As BWT ultrasound cannot identify bladder dysfunction of children with spina bifida, this cannot be used as a substitute for invasive urodynamics.

Uroflowmetric analysis and derivation of nomograms for normal paediatric Indian population between 5 to 15 years of age

Objective

We aimed to established normal uroflowmetric values and subsequently derived nomograms of maximum flow rate (Q_max) and average flow rate (Q_avg) against voided volume (VV) in children aged 5–15 years at our institute.

Methods

A total of 440 children underwent uroflowmetric evaluation with no history of urological, renal, psychiatric, or neurological disorder between 5 and 15 years of age. Each subject data regarding Q_max, Q_avg, VV, time to Q_max, and flow time, as well as age, sex, height, and weight were recorded. Of the 440 children, around 300 (68.18%) children could produce a normal flow rate at VV of more than 50 mL. Of the remaining 140 (31.82%) children, 50.00% voided less than 50 mL, and remaining 50.00% had abnormal voiding pattern, staccato or interrupted (21.43% each) and plateau or tower shaped (3.57% each). Cases were divided into two age groups (5–9 years and 10–15 years), and uroflowmetric analysis was done between boys and girls in both age groups to derive nomograms of Q_avg and Q_max.

Results

Q_max and Q_avg flow nomograms were plotted for boys and girls. Mean Q_max for boys was 16.68 mL/s and for girls 20.69 mL/s. The mean Q_avg values were 11.04 mL/s and 8.60 mL/s for girls and boys, respectively. The Q_max and Q_avg values were higher in girls. There were significant increases in flow rates with increasing age, body surface area, and VV in both sexes.

Conclusions

Nomograms for Q_max and Q_avg may be a useful tool in evaluation of lower urinary tract disturbances in children.

Bladder Point-of-Care Ultrasound: A Time Saver in the Pediatric Emergency Department

BACKGROUND

Pediatric patients undergoing transabdominal pelvic ultrasound require a full bladder as an acoustic window. Patients are typically relied upon to subjectively identify bladder fullness, but inaccurate reporting often leads to delays in test results, diagnosis, and treatment.

OBJECTIVES

Our aim was to objectively evaluate bladder fullness by comparing the height of the bladder to the height of the uterus on point-of-care ultrasound (POCUS). Our hypothesis was that this method would result in faster time to imaging and decrease emergency department length of stay (ED LOS).

METHODS

Bladder fullness was assessed using POCUS every 30 min until the bladder was full. If the height of the bladder was equal to or greater than the height of the uterus in the sagittal view, the bladder was considered full. The POCUS group was compared with a control group that relied solely on patients' self-identified bladder fullness.

RESULTS

Females aged 8-18 years old with pelvic pain in the pediatric ED were included in the study. Forty POCUS patients were compared with a control group of 105 patients. The POCUS group demonstrated a decrease in time to pelvic imaging by 38.7 min (95% confidence interval -59.2 to -18.2; p < 0.0001) and a decrease in LOS by 49.2 min (95% CI -89.7 to -8.61; p = 0.004). There was poor overall agreement on bladder fullness between patient's subjective sensation and POCUS (k = 0.04).

CONCLUSION

POCUS to evaluate bladder fullness by comparing the height of the bladder with the height of the uterus reduces time to pelvic imaging and ED LOS.

Bladder and voiding dysfunction in adolescents with anorexia nervosa: a novel finding and potential causes

PURPOSE

This study aimed to investigate the bladder capacity (BC) and bladder dynamics of adolescents with anorexia nervosa (AN).

METHODS

The participants consisted of 15 adolescents newly diagnosed with AN according to the DSM 5 criteria and in the acute weight loss period who were questioned about the symptoms of lower urinary tract (LUT) dysfunction. Functional bladder capacity (FBC) and voided volume with uroflowmetry were measured for each subject; the larger volume of the two was chosen for the bladder capacity. Uroflowmetry was used to obtain uroflow curves for the participants whose patterns were labeled as pathologic if they were outside the bell-shape.

RESULTS

Fourteen (93.3%) of the patients exhibited at least one of the LUT dysfunction symptoms (pathologic voiding symptom/urinary incontinence/pathologic uroflow pattern). BC was observed to increase in 86.6% (n = 13) of the patients. Eighty% of the patients (n = 12) showed pathological uroflow patterns. In patients with pathological uroflow patterns, which showed insufficiency of bladder contraction, assistance of abdominal muscles was needed during voiding.

CONCLUSION

The novel findings presented in this study are the increase of BC in adolescents with AN, the presence of at least one type of voiding or bladder dysfunction, and the pathology of uroflow patterns of most patients show that the bladder dynamics is affected in AN. The most important contribution of this study to the literature is that impaired bladder dynamics was determined to be a medical complication of AN.

LEVEL OF EVIDENCE

Case-control analytic study, Level III.

Evaluation of Functional Bladder Capacity in Children with Nocturnal Enuresis According to Type and Treatment Outcome

Purpose

This study aimed to identify whether functional bladder capacity (FBC) differs among subgroups of nocturnal enuresis (NE) patients and can be used to predict treatment response.

Methods

A total of 69 children with NE were included in this study between July 2017 and February 2019 according to medical chart review, retrospectively. All patients completed a questionnaire about voiding symptoms and 48-hour frequency/volume (48-h F/V) charts. FBC was obtained from the 48-h F/V charts and uroflowmetry (UFM) with post-void residual volume (PVR). All patients were primarily treated with standard urotherapy and pharmacological therapy. The response rate was analyzed at 3 months after treatment.

Results

The mean age of the 69 patients (42 male, 27 female) was 83.3 ± 22.4 months (range, 5–13 years) at the first visit. The percentages of children with monosymptomatic NE (MNE) and non-monosymptomatic NE (NMNE) on the questionnaire were 40.6% (28/69) and 59.4% (41/69), respectively. FBC of all patients was lower than the normal range of expected bladder capacity, and there were no significant differences between measurement methods, NE types (MNE vs NMNE), or response rates (p > 0.05).

Conclusion

Children with NE had diminished FBC in both 48-h F/V charts and UFM with PVR. We found no difference in FBC by NE type or treatment outcome. Therefore, FBC cannot be used to distinguish between NE types or predict treatment responses.

Pediatric cystogram: Are we considering age-adjusted bladder capacity?

INTRODUCTION

There are a small number of reports in the literature describing bladder rupture during cystograms in children. We hypothesized that children undergoing cystograms may have their bladder overfilled during the test. We aimed to evaluate the current practice when performing cystograms in our institution, contrasting actual volume used to fill the bladder to the age-adjusted bladder capacity.

METHODS

We performed a retrospective review of all voiding cystourethrograms(VCUG) and radionuclide cystograms (RNC) performed at the Children's Hospital of Eastern Ontario from 2006-2013. Formulas used to estimate age-adjusted bladder capacity: 1) infants <1 year: Capacity (mL) = (2.5 × age [months]) + 38 (Holmdahl et al, 1996); and 2) older children >1 year: Capacity (mL) = (2 + age [years]) × 30 (Koff et al, 1983).

RESULTS

A total of 2411 cystograms were done (1387 VCUG; 1024 RNC) in 817 infants and 1594 children older than one year - 1113 boys and 1298 girls. Generally, bladders tended to be overfilled with 32% more volume in mL than the expected age-adjusted bladder capacity - VCUG 151 (122) mL vs 120 (97) mL (p< 0.001) and RNC 191 (97) mL vs. 151(74) mL (p<0.001). Most importantly, infants had a striking overfilling rate of 64% and 38 % more volume than their expected age-adjusted bladder capacity for VCUG and RNC, respectively (p<0.001).

CONCLUSION

Bladders are filled above the estimated age-adjusted capacity in mL at the following rates: 32% in the whole group and 64% in infants undergoing VCUG. It raises concern of possible bladder rupture in this age group. Furthermore, this may lead to overgrading and overdiagnosing of vesicoureteric reflux, as well as overestimation of post-void residual. Attention should be paid to filling to age-adjusted bladder capacity and allowing the child adequate time to void during performance of the cystogram.

Ureteral tunnel length versus ureteral orifice configuration in the determination of ureterovesical junction competence: A computer simulation model

INTRODUCTION

The long-held belief that a ureteral re-implant tunnel should be five times the diameter of the ureter, as proposed by Paquin in 1959, ignores the effect of the orifice on the occurrence of reflux. In 1969, Lyon proposed that the shape of the ureteral orifice (UO) is more important than the intravesical tunnel. However, both theories missed quantitative evidence from principles of physics. The goal of the current study was to test Lyon's theory through numerical models (i.e. to quantify the sensitivity of ureterovesical junction (UVJ) competence to intravesical tunnel length and to the UO).

MATERIALS AND METHODS

The closure of a three-dimensional spatial configuration of ureter, constrained within a bladder, was simulated. Two common UO shapes (i.e. golf type vs 2-mm volcano type (Summary Fig.)), and two different intravesical ureteral tunnel length/diameter ratios (3:1 and 5:1) were examined. The required closure pressures were then compared.

RESULTS

The UO was a significant factor in determining closure pressure. Given the same intravesical ureteral tunnel length/diameter ratio, the required closure pressure for the volcanic orifice was 78% less than that for the golf orifice. On the other hand, the intravesical ureteral tunnel length/diameter ratio had minimal effect on the required closure pressure. As the intravesical ureteral tunnel length/diameter ratio changed from 3:1 to 5:1, the required closure pressure was reduced by less than 7%, regardless of the orifice shape.

CONCLUSIONS

The simulation results showed that UVJ competence was more sensitive to a 2-mm protrusion of the UO compared to an increase in the intravesical tunnel length from 3:1 to 5:1. This agrees with Lyon's theory, and at the same time challenges Paquin's 5:1 rule. Researchers could use this information to consider the UO configuration in further animal, human, computer or material models.

Risk Factors Associated With Recurrent Urinary Tract Infection in Neurogenic Bladders Managed by Clean Intermittent Catheterization

OBJECTIVE

To identify risk factors for recurrent urinary tract infection (UTI) in patients who perform clean intermittent catheterization (CIC).

METHODS

A 6-year retrospective chart review of patients with spina bifida or tethered cord who perform clean intermittent catheterization (8 months to 58 years) was conducted. A strict case definition for UTI was applied, and per-subject UTI events, demographic, and clinical data were abstracted. Data were compared between groups defined by no or infrequent UTI (≤1.0 UTI/study year) and frequent UTI (>1.0 UTI/study year).

RESULTS

Of 194 total patients, 146 (75%) had no UTIs or infrequent UTIs, and 48 (25%) patients had frequent UTIs. On univariate analysis, only younger age and suprasacral cord lesions were associated with frequent UTIs (P = .002 and P = .007, respectively). Among the 128 patients with urodynamic studies, bladder capacity, compliance, detrusor overactivity, and detrusor leak point pressure were not associated with frequent UTI on univariate analysis. On multivariate analysis, increasing age was found to be associated with decreased odds of UTI by 7% per year (odds ratio 0.93, P = .016).

CONCLUSION

The risk of UTI among individuals with spina bifida or tethered cord declines with increasing age. Bladder function based on urodynamic parameters did not correlate with frequent UTIs.

Design and Methodological Considerations of the Centers for Disease Control and Prevention Urologic and Renal Protocol for the Newborn and Young Child with Spina Bifida

PURPOSE

Care of children with spina bifida has significantly advanced in the last half century, resulting in gains in longevity and quality of life for affected children and caregivers. Bladder dysfunction is the norm in patients with spina bifida and may result in infection, renal scarring and chronic kidney disease. However, the optimal urological management for spina bifida related bladder dysfunction is unknown.

MATERIALS AND METHODS

In 2012 the Centers for Disease Control and Prevention convened a working group composed of pediatric urologists, nephrologists, epidemiologists, methodologists, community advocates and Centers for Disease Control and Prevention personnel to develop a protocol to optimize urological care of children with spina bifida from the newborn period through age 5 years.

RESULTS

An iterative quality improvement protocol was selected. In this model participating institutions agree to prospectively treat all newborns with spina bifida using a single consensus based protocol. During the 5-year study period outcomes will be routinely assessed and the protocol adjusted as needed to optimize patient and process outcomes. Primary study outcomes include urinary tract infections, renal scarring, renal function and bladder characteristics. The protocol specifies the timing and use of testing (eg ultrasonography, urodynamics) and interventions (eg intermittent catheterization, prophylactic antibiotics, antimuscarinic medications). Starting in 2014 the Centers for Disease Control and Prevention began funding 9 study sites to implement and evaluate the protocol.

CONCLUSIONS

The Centers for Disease Control and Prevention Urologic and Renal Protocol for the Newborn and Young Child with Spina Bifida began accruing patients in 2015. Assessment in the first 5 years will focus on urinary tract infections, renal function, renal scarring and clinical process improvements.

The Effect of a Full Bladder on Proportions of Diagnostic Ultrasound Studies in Children with Suspected Appendicitis

OBJECTIVES

We examined the effect of a full bladder on proportions of diagnostic ultrasound (US) studies in children with suspected appendicitis. We also examined the effect of a full bladder on proportions of fully visualized ovaries on US in children with suspected appendicitis.

METHODS

We conducted a retrospective health record review of children aged 2-17 years presenting to a tertiary pediatric emergency department (ED) with suspected appendicitis who had an ultrasound performed. We compared proportions of diagnostic US studies in children with full and sub-optimally filled bladders. We also compared proportions of ovarian visualization in females with full and sub-optimally filled bladders.

RESULTS

678 children were included in our final analysis. The proportion of diagnostic US studies did not vary significantly between groups with a full (132/283, 47%, 95% confidence interval [CI] 38%-56%) or sub-optimally filled bladder (205/395, 52%, 95% CI 47%-57%)(p=0.17). Rates of ovarian visualization were higher in females with a full bladder (196/205, 96%, 95% CI 93%-99%) compared to those with a sub-optimally filled bladder (180/223, 81%, 95% CI 76%-86%) (p<0.01).

CONCLUSIONS

Administrators and clinical decision makers should consider removing routine bladder filling practice from current pediatric appendicitis protocols in males and in pre-pubertal females where ovarian pathology is not suspected. Selective bladder filling prior to US should be performed in females when ovarian pathology is suspected.

Bladder rupture after voiding cystourethrography: A case report and literature review on pitfalls and bladder volume estimation

Voiding cystourethrography (VCUG) is a common diagnostic study in pediatric urology. Although generally considered a safe procedure, VCUG can incur some complications. Bladder rupture following VCUG is a very rare complication and mostly happens in the setting of unused bladders, previous surgeries, or underlying disease. The rupture is almost always intraperitoneal needing prompt surgical treatment. We present a unique case of extraperitoneal bladder rupture after VCUG in an 8-month-old boy. The rupture remained unnoticed and the patient recovered spontaneously without medical or surgical intervention. To the best of our knowledge, this is the first such case report in the English literature. The information provided may guide clinicians on the proper use of bladder volume formulas in children and also help them in getting a proper VCUG study.

Outcomes of living donor renal transplantation in children with lower urinary tract dysfunction: a comparative retrospective study

OBJECTIVES

To compare outcomes of renal transplantation (RTx) in children with end-stage renal disease (ESRD) resulting from lower urinary tract dysfunction (LUTD) vs other causes.

PATIENTS AND METHODS

A database of children (<18 years old) who underwent RTx between May 2008 and April 2012 was reviewed. Patients were divided into those with LUTD (group A, n = 29) and those with other causes of ESRD (group B, n = 74). RTx was performed after achieving low intravesical pressure (<30 cmH2 O) with adequate bladder capacity and drainage. The groups were compared using Student's t-test, Mann-Whitney, chi-squared or exact tests. Graft survival rates (GSRs) were evaluated using Kaplan-Meier curves and the log-rank test.

RESULTS

The mean ± sd (range) age of the study cohort was 5.05 ± 12.4 (2.2-18) years. Causes of LUTD were posterior urethral valve (PUV; 41.4%), vesico-ureteric reflux (VUR; 37.9%), neurogenic bladder (10.3%), prune belly syndrome (3.4%), obstructive megaureter (3.4%) and urethral stricture disease (3.4%). There was no significant difference in age, dialysis duration or donor type. In group A, 25 of the 29 patients (86.2%) underwent ≥1 surgery to optimize the urinary tract for allograft. Pretransplant nephrectomy was performed in 15 of the 29 patients (51.7%), PUV ablation in nine patients (31%) and ileocystoplasty in four patients (13.7%). The mean ± sd follow-up was 4.52 ± 1.55 and 4.07 ± 1.27 years in groups A and B, respectively. There was no significant difference in creatinine and eGFR between the groups at different points of follow-up. The GSRs at the end of the study were 93.1 and 91.1% in groups A and B, respectively (P = 1.00). According to Kaplan-Meier survival curves, there was no significant difference in the GSR between the groups using the log-rank test (P = 0.503). No graft was lost as a result of urological complications. In group B, one child died from septicaemia. The rate of urinary tract infections was 24 and 12% in groups A and B, respectively, but was not significant. No significant difference was found between the groups with regard to the incidence of post-transplantation hydronephrosis. Of the 22 patients who had hydronephrosis after transplantation, three were complicated by UTI. Injection of bulking agents was required in two patients for treatment of grade 3 VUR. In the third patient, augmentation cystoplasty was needed.

CONCLUSION

Acceptable graft function, survival and UTI rates can be achieved in children with ESRD attributable to LUTD. Thorough assessment and optimization of LUT, together with close follow-up, are key for successful RTx.

Robot-assisted Laparoscopic Augmentation Ileocystoplasty and Mitrofanoff Appendicovesicostomy in Children: Updated Interim Results

BACKGROUND

Robot-assisted laparoscopic augmentation ileocystoplasty with Mitrofanoff appendicovesicostomy (RALIMA) may protect the upper urinary tract and reestablish continence in patients with refractory neurogenic bladder. Robotic assistance can provide the benefits of minimally invasive surgery without the steep learning curve of pure laparoscopy.

OBJECTIVE

To highlight the interim outcomes of RALIMA with salient tips and technical modifications through comparison with patients undergoing open augmentation ileocystoplasty (OAI).

DESIGN, SETTINGS, AND PARTICIPANTS

A retrospective chart review of 17 patients undergoing robot-assisted laparoscopic augmentation ileocystoplasty (RALI) and 13 patients undergoing OAI by a single surgeon at an academic center from 2008 to 2012 (OAI) or 2014 (RALI).

SURGICAL PROCEDURE

RALI and all concomitant procedures were performed completely intracorporeally using the da Vinci surgical system (Intuitive Surgical, Inc., Sunnyvale, CA, USA).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Outcomes of interest included change in bladder capacity, operative time, pain medication use, hospitalization time, and perioperative complication rates.

RESULTS AND LIMITATIONS

Of 17 patients selected, 15 successfully underwent RALI. Overall, 11, 6, and 4 patients had a concomitant Mitrofanoff appendicovesicostomy, antegrade colonic enema channel, and bladder neck closure, respectively. The median operative time was significantly longer in RALI (623 vs 287 min; p<0.01). Median length of stay (LOS) was shorter in RALI (6 vs 8 d; p=0.01). The postoperative percentage increase in bladder capacity, narcotic use, and complication rates did not differ between RALI and OAI. Limitations include the retrospective study design and the small cohort of patients.

CONCLUSIONS

RALI appears to offer functional outcomes similar to OAI. Although it is a significantly longer procedure, it may decrease LOS and avoid epidural use. Further refinements may reduce operative time.

PATIENT SUMMARY

In this report, we examined outcomes after robotic bladder augmentation surgery in children. We found that the robotic approach may eliminate epidural analgesia use and decrease hospitalization time after surgery.

Are we accurately predicting bladder capacity in infants?

INTRODUCTION

Estimating bladder capacity is an important component in the evaluation of many urological disorders. For estimates to be of clinical value, precise reference ranges are needed. While accepted reference ranges have been established in adults and older children, none have been validated in infants. We endeavour to determine the normal bladder capacity of children less than 1 year of age.

METHODS

We retrospectively reviewed the charts of children aged 0 to 12 months with cutaneous stigmata of spinal dysraphism who were referred to the urology clinic to rule out tethered cord between October 2004 and July 2011. Patients with normal urologic assessment, who did not have surgery during the time they were followed, were included in the study cohort. Urodynamic studies were performed using the Laborie Medical Technologies UDS-600. Bladder filling occurred via a catheter at a rate of 10% of the expected total bladder capacity/minute. Bladder capacity was defined as the volume of filling when the child voided around the catheter. We collected data, including age at urodynamics, bladder capacity, detrusor pressure at capacity, bladder compliance and length of follow-up.

RESULT

In total, 46% (84/183) of patients had a normal urologic assessment and met the inclusion criteria. The median age was 9.0 months (interquartile range [IQR] 6.8-11.0). The average bladder capacity was 48.9 mL (standard deviation [SD] 32.8) and the mean detrusor pressure at capacity was 8.5 cmH2O (SD 10.0). Mean compliance was 14.1 mL/cmH2O (SD 13.6). The average length of follow-up was 40.7 months (SD 26.2) and during this interval no patients were found to have urologic or neurologic abnormalities and none underwent tethered cord release.

CONCLUSION

Bladder capacity in infants with a median age of 9.0 months was found to be 48.9 mL. This is less than half of the volume predicted by a commonly employed formula. A novel method of estimating bladder capacity in infants is required.

Bladder exstrophy: current management and postoperative imaging

Bladder exstrophy is a rare malformation characterized by an infra-umbilical abdominal wall defect, incomplete closure of the bladder with mucosa continuous with the abdominal wall, epispadias, and alterations in the pelvic bones and muscles. It is part of the exstrophy-epispadias complex, with cloacal exstrophy on the severe and epispadias on the mild ends of the spectrum. Bladder exstrophy is the most common of these entities and is more common in boys. The goal of this paper is to describe common methods of repair and to provide an imaging review of the postoperative appearances.

Role of vesicostomy in the management of posterior urethral valve in Sub-Saharan Africa

OBJECTIVE

To review the role of vesicostomy in the management of posterior urethral valve (PUV), in neonates and infants, given the limitations for endoscopic treatment in this setting.

METHODS

A review of 35 patients who presented with posterior urethral valve over a 10-year period. Demographic and clinical information were prospectively recorded on a structured pro forma, and the data extracted analysed using SPSS 11.0.

RESULTS

The 35 boys were aged 3 days to 10 years (median 3 weeks). Twenty-three (65.7%) had a vesicostomy (age range 3 days-3 years, median 3 weeks). The mode of presentation was poor urinary stream 15 (65.2%), urinary retention 4 (17.4%), and renal failure 6 (26.1%). Main findings were palpable bladder 23 (100%), hydronephrosis 4 (17.4%). Abdominal ultrasound confirmed hydronephrosis and thickened bladder wall, and voiding/expressive cystourethrogram confirmed dilated posterior urethra and vesicoureteric reflux in all 23 patients. Complications following vesicostomy were stoma stenosis 1 (4.3%), bladder mucosal prolapse 1 (4.3%), perivesicostomy abscess 1 (4.3%); there was no mortality. Following vesicostomy, 10 (43.5%) patients had excision of the valves and vesicostomy closure at age 2-8 years (median 4 years). They are well, with normal renal ultrasonographic findings, bladder capacity range 115-280 ml, and normal urea, serum electrolytes, creatinine, at 3 years of follow up. Thirteen (56.5%) are still awaiting valvotomy but have remained well and with normal ultrasonographic renal findings.

CONCLUSION

Vesicostomy is a useful temporising mode of urinary diversion in neonates and infants with posterior urethral valve (in the absence of unobstructed upper tracts) when facilities for endoscopic valve ablation are not readily available.

New contralateral vesicoureteral reflux after unilateral ureteral reimplantation: predictive factors and clinical outcomes

PURPOSE

Although unilateral ureteral reimplantation for vesicoureteral reflux is highly successful, new contralateral reflux will develop postoperatively in some patients. We examined predictors and clinical outcomes of postoperative contralateral vesicoureteral reflux.

MATERIALS AND METHODS

We reviewed patients who underwent nontapered unilateral reimplantation for primary vesicoureteral reflux graded on a 3-point scale at our institution from January 1990 to December 2002, and identified those with subsequent contralateral vesicoureteral reflux. We analyzed the association of patient/procedure characteristics with incidence, and time to resolution of contralateral reflux and postoperative urinary tract infection. Multivariable models controlled for variables associated with incidence and time to resolution of contralateral reflux.

RESULTS

A total of 395 patients (77.2% female, median age 5.3 years) underwent ureteral reimplantation for vesicoureteral reflux. Preoperative reflux was grade 1 in 2.8% of patients, grade 2 in 56.6% and grade 3 in 40.6%. Technical success was 95.4%. After reimplantation 39 patients (9.9%) had new contralateral reflux (grade 1 in 7, grade 2 in 27 and grade 3 in 5). Median followup was 51.8 months. On multivariate analysis younger age (less than 6 years, OR 3.7, p = 0.006) and low observed bladder capacity as percent of predicted bladder capacity (less than 50% of predicted capacity, OR 6.3, p = 0.02) were significant predictors of contralateral reflux. Contralateral reflux resolved in 21 of 27 patients (77.8%) on subsequent cystography at a median of 21.5 months. Two patients underwent reimplantation for persistent contralateral reflux. Four of 39 patients (10.3%) with contralateral reflux had postoperative febrile urinary tract infections at a median of 26 months, with spontaneous resolution of contralateral reflux in all.

CONCLUSIONS

Younger patients and those with low observed vs predicted bladder capacity may be at increased risk for postoperative contralateral vesicoureteral reflux. A majority of contralateral reflux will resolve spontaneously, and the clinical course is typically benign.

Lower urinary tract development and disease

Congenital anomalies of the lower urinary tract (CALUT) are a family of birth defects of the ureter, the bladder, and the urethra. CALUT includes ureteral anomaliesc such as congenital abnormalities of the ureteropelvic junction (UPJ) and ureterovesical junction (UVJ), and birth defects of the bladder and the urethra such as bladder-exstrophy-epispadias complex (BEEC), prune belly syndrome (PBS), and posterior urethral valves (PUVs). CALUT is one of the most common birth defects and is often associated with antenatal hydronephrosis, vesicoureteral reflux (VUR), urinary tract obstruction, urinary tract infections (UTI), chronic kidney disease, and renal failure in children. Here, we discuss the current genetic and molecular knowledge about lower urinary tract development and genetic basis of CALUT in both human and mouse models. We provide an overview of the developmental processes leading to the formation of the ureter, the bladder, and the urethra, and different genes and signaling pathways controlling these developmental processes. Human genetic disorders that affect the ureter, the bladder and the urethra and associated gene mutations are also presented. As we are entering the postgenomic era of personalized medicine, information in this article may provide useful interpretation for the genetic and genomic test results collected from patients with lower urinary tract birth defects. With evidence-based interpretations, clinicians may provide more effective personalized therapies to patients and genetic counseling for their families.

Uroflowmetry nomograms for healthy children 5 to 15 years old

PURPOSE

We determined flow rates and generated flow rate-voided volume nomograms based on healthy children 5 to 15 years old voiding spontaneously in their natural environment.

MATERIALS AND METHODS

A total of 824 healthy school children of both genders were enrolled. A single uroflow record from each child was evaluated. A total of 103 children with a voided volume of less than 50 ml and/or a staccato/interrupted uroflow pattern were excluded, and 721 records were analyzed. Data were evaluated using several mathematical formulas and goodness of fit was determined. Linear regression analysis was used to generate nomograms.

RESULTS

Flow rates and voided volumes increased with increasing age, with the effect being more pronounced in girls. No significant difference was noted in uroflow rates from 5 to 10 years, but significant differences (p <0.001) started appearing at 11 to 15 years. Also no significant difference was noted in uroflow rates among children 11 to 15 years. Therefore, 2 age groups were designated, with group 1 consisting of patients 5 to 10 years old and group 2 consisting of patients 11 to 15 years old. There were 222 boys and 122 girls in group 1 and 240 boys and 137 girls in group 2. In group 1 the maximum and average ± SD flow rates were 15.26 ± 4.54 ml per second and 7.68 ± 3.26 ml per second, respectively, for boys and 17.98 ± 6.06 ml per second and 9.19 ± 4.23 ml per second, respectively, for girls. In group 2 these rates were 22.50 ± 7.24 ml per second and 10.78 ± 4.03 ml per second, respectively, for boys and 27.16 ± 9.37 ml per second and 13.48 ± 5.21 ml per second, respectively, for girls.

CONCLUSIONS

This large study, which expands the scant existing literature on uroflow parameters in healthy children, will hopefully promote wider application of uroflowmetry testing in the pediatric population.

Does hydronephrosis predict the presence of severe vesicoureteral reflux?

We hypothesized that, in patients with vesicoureteral reflux (VUR) grade IV or V, hydronephrosis will likely be found, if the patient has a full bladder during the renal ultrasound examination. Eight hundred thirty-seven patients were included in the study. Patients ranged in age from <1 month to 18.7 years, with a median age of 1.3 years. Five hundred sixty-nine were female and 268 were male. In this retrospective study, each patient underwent a voiding cystourethrogram (VCUG) and a renal ultrasound examination. The presence of hydronephrosis and bladder filling status in 131 renal units with VUR grade IV or V was evaluated. Sensitivity and specificity for hydronephrosis to detect the presence of VUR grades IV and V were 60 and 92 %, respectively. Positive predictive value and negative predictive value were 74 and 87 %, respectively. Odds ratios for the relationship between hydronephrosis and severe VUR was significant (p = 0.046).

CONCLUSION

In patients with grade IV or V VUR, hydronephrosis will be observed in the presence of a full bladder. Therefore, a renal ultrasound could be considered a screening test to decide on performing a VCUG.

Twelve-hour daytime observation of voiding pattern in newborns <4 weeks of age

AIM

To investigate the voiding pattern in <4-week-old newborns by 12-h daytime observation periods.

METHODS

Twenty-one healthy 1- to 28-day-old newborns were included (10 full term, 11 preterm). The 12-h free voiding parameters, including voiding frequency (VF), voiding volume (VV), post-voiding residual volumes (PRV) and status at voiding (awake/sleep), were recorded at day 1, 4, 7, 14 and 28 after birth.

RESULTS

Voiding was recorded 778 times. VF increased in the full-term and preterm newborns between day 4 and 7, decreased in preterms between day 14 and 28, but remained higher than in the full terms. VV increased twice in full terms and once in preterms during 28 days and PRV fluctuated. In contrast, VV was higher in the full term than in the preterms at days 4, 7, 14 and 28. PRV was higher at days 4 and 28. Interrupted voiding was less frequent in the full term than in the preterms.

CONCLUSION

Voiding pattern in the preterms differed in many ways from that of the full-term newborns. Frequent interrupted and incomplete voiding pattern in the preterm newborns indicates a disrupted coordination of the detrusor-sphincter and a delayed maturation of the neural micturition centre.

Evaluation of maximum voided volume in Korean children by use of a 48-h frequency volume chart

Study Type - Diagnostic (validating cohort). Level of Evidence 2a. What's known on the subject? and What does the study add? The relationship between the maximum voided volume followed a linear curve. The formula presented, bladder capacity (mL) = 12 ×[age (years) + 11], is thought to be a reasonable one for Korean children. Korean children have a smaller bladder capacity than that reported in previous Western studies.

OBJECTIVE

• To develop practical guidelines for the prediction of normal bladder capacity in Korean children measured by a frequency volume chart (FVC), maximum voided volume (MVV) is an important factor in the diagnosis of children with abnormal voiding function.

SUBJECTS AND METHODS

• In all, 298 children, aged 3-13 years, with no history of voiding disorders volunteered for the study. The MVV was determined in 219 subjects by use of a completely recorded FVC.

RESULTS

• Linear regression analysis was used to define the exact relationship between age and bladder capacity. An approximate formula related age to bladder capacity as follows: bladder capacity (mL) = 12 ×[age (years) + 11].

CONCLUSIONS

• The relationship between the MVV measured by a FVC by age (3-13 years) of Korean children followed a linear curve. • When applied to normal voiding patterns, the formula presented appears to be a reasonable one for Korean children.

A healthy bladder: a consensus statement

A panel of experts in urology, urogynecology, nursing, and behavioral therapy convened in 2010 to discuss the importance of a healthy bladder on overall health. They determined that a consensus statement was necessary to raise awareness among the general public, healthcare providers, payors, and policymakers, with the goals of minimizing the impact of poor bladder health and stimulating primary prevention of bladder conditions. In this statement, 'healthy' bladder function is described, as well as internal and external factors that influence bladder health. It is suggested that primary prevention strategies should be aimed at providing education regarding normal lower urinary tract structures and functioning to the public, including patients and healthcare providers. This education may promote the achievement of optimal bladder health by increasing healthy bladder habits and behaviors, awareness of risk factors, healthcare seeking, and clinician engagement and reducing stigma and other barriers to treatment. Promoting optimal bladder health may reduce the personal, societal and economic impact of bladder conditions, including anxiety and depression and costs associated with conditions or diseases and their treatment. While adopting healthy bladder habits and behaviors and behaviors may improve or maintain bladder health, it is important to recognize that certain symptoms may indicate the presence of conditions that require medical attention; many bladder conditions are treatable with a range of options for most bladder conditions. Lastly, the authors propose clinical directives based on persuasive and convergent research to improve and maintain bladder health. The authors hope that this statement will lead to promotion and achievement of optimal bladder health, which may improve overall health and help minimize the effects of bladder conditions on the public, healthcare professionals, educators, employers, and payors. The advisors are in consensus regarding the recommendations for improving and maintaining bladder health presented herein.

Echocontrast cystosonography versus micturating cystourethrography in the detection of vesicoureteric reflux

Purpose:

To compare echocontrast cystosonography (ECS) using in-vivo agitated saline with fluoroscopic micturating cystourethrography (MCU) in the detection and grading of vesicoureteric reflux (VUR).

Materials and methods:

This was a prospective study of 25 children, who had MCU between 2007 and 2009. ECS was performed and findings documented prior to MCU. Baseline renal and bladder sonograms were obtained. The bladder was filled with normal saline followed by introduction of 10–20 mls of air to generate microbubbles. Detection of VUR was based on two sonographic criteria: (1) presence of microbubbles in the pelvicaliceal system (PCS), and (2) increase in dilatation of the PCS. VUR was graded as (1) Grade I: microbubbles seen in ureter only; (2) Grade II: microbubbles seen in non-dilated PCS; and (3) Grade III-V: microbubbles seen in dilated PCS. The ECS findings were compared using MCU as the gold standard.

Results:

Of the 50 kidney-ureter (K-U) units studied, ECS detected 9 of 10 K-U units with VUR on MCU. ECS did not detect a Grade II VUR. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value for criterion 1 was 90%, 87.5%, 88%, 64.3% and 97%, respectively, compared to criterion 2 which was 70%, 90%, 86%, 64% and 92%, respectively. The grading of VUR was similar on both ECS and MCU except for one case.

Conclusion:

ECS using agitated saline was a sensitive technique for the detection of VUR. ECS grading was comparable with MCU grading of VUR.

Pediatric kidney recipients with small capacity, defunctionalized urinary bladders receiving adult-sized kidney without prior bladder augmentation

BACKGROUND

Children with small capacity, defunctionalized urinary bladders present unique operative challenges. Thus, traditional practice has included pretransplant bladder augmentation, but this has several adverse consequences.

METHODS

A single-institutional, retrospective review from January 1, 2004 to December 31, 2008 was conducted. Twelve pediatric patients, whom had not undergone pretransplant bladder augmentation, did not have neurogenic bladders or require preoperative catheterization, and a small capacity defunctionalized bladders were included. All were managed by the same surgeon with a previously described ureteral implantation, and a 7F ureteral stent attached to a large diameter suprapubic catheter was removed in a joint manner without cystoscopy at 2 weeks. Data were collected on patient and graft survival, rejection episodes, urinary tract infection (UTI) requiring antibiotics, grade of vesicoureteral reflux, and posttransplant bladder capacity.

RESULTS

One-year patient and graft survival rates were 100%. One patient experienced a clinical rejection episode, which was successfully treated. Five patients (41.7%) had a UTI requiring abx treatment within the first postoperative year, but at 1 year, all patients had sterile urinary tracts. After removal of suprapubic catheters and ureteral stents, all patients were able to void spontaneously. Seven patients had no posttransplant ureteral reflux, three had grade 1 reflux, and two had grade 3 reflux (both successfully treated). The average age estimated pretransplant bladder and 1 year posttransplant bladder capacity was 14.5% and 84% of expected, respectively.

CONCLUSIONS

In pediatric end-stage renal disease patients with a small capacity defunctionalized bladder, it is reasonable to proceed with kidney transplantation without pretransplant bladder augmentation, thus avoiding an unnecessary surgery.

Catheterizable serous lined urinary outlet in children and adolescents: a choice when other treatments fail

PURPOSE

We evaluated the functional outcome of continent catheterizable outlet using the serous lined extramural tunnel technique as a continence mechanism in children and adolescents.

MATERIALS AND METHODS

We retrospectively studied all patients who underwent continent catheterizable stoma using the serous lined extramural technique between May 1993 and March 2008. Patient records were reviewed for age, sex, indication for surgery, surgical details and postoperative course. All patients were evaluated for continence with emphasis on frequency of clean intermittent catheterization. Urodynamic evaluation was done for patients with leaking stoma. Stoma related complications were also recorded.

RESULTS

A total of 37 boys and 23 girls 3 to 18 years old underwent continent catheterizable stoma using the serous lined extramural technique. Total bladder substitution was performed in 13 patients using continent ileal W-shaped reservoir, and 47 patients underwent augmentation ileocystoplasty mounted with serous lined outlet. The outlet channel was appendix in 39 patients (65%), tapered ileal segment in 13 (21.5%) and Monti ileal tube in 8 (13.5%). After a median followup of 43 months (range 10 to 180) 55 patients (91.6%) achieved continence, with catheterization frequency of 3 to 5 times during the daytime and 1 to 2 times at night. Stoma related complications were leaking stoma in 5 patients (8.4%), stomal stenosis in 6 (10%), parastomal hernia in 2 (3.3%) and reservoir stones in 8 (13.3%). Reoperation rate was 18.3% (11 patients).

CONCLUSIONS

The serous lined continent outlet seems to be a durable and efficient technique for treating children with incontinence, with an acceptable complication rate.

Bladder volume on voiding cystourethrogram correlates with indications and results in male infants

OBJECTIVES

To evaluate whether the bladder size on the voiding cystourethrogram (VCUG) might be a proxy for voiding abnormalities. Voiding abnormalities have been implicated in the development of hydronephrosis, reflux, and urinary tract infections.

METHODS

We evaluated the volume of contrast infused for 617 consecutive VCUGs. We compared the actual volume infused during the VCUG to the expected bladder capacity. We correlated the percentage of predicted capacity with (a) the reason for the VCUG; (b) the VCUG results; (c) the patient's sex; and (d) their body mass index. We analyzed the results for the entire group, as well as by age, sex, reflux grade, and body mass index. We also examined the findings from those patients undergoing consecutive studies.

RESULTS

The bladder size on the VCUG was greater than predicted (1.74 times predicted). This was particularly true for patients <2 years old (2.22 vs 1.41 times predicted; P < .001) and for boys (2.01 vs 1.63 times predicted; P < .001). Both the reason for the VCUG (more prenatal patients with hydronephrosis than others; P < .001) and the VCUG findings (new reflux found more than others) had a relationship with the bladder size on the VCUG (P < .001). The body mass index did not correlate with the bladder size on the VCUG. Of the 87 patients undergoing 2 studies, the 53 patients with either no or improved reflux on the second study tended to have a larger than predicted bladder size on the VCUG (P = .07).

CONCLUSIONS

The bladder volume on the VCUG was greater than predicted for male infants with prenatal hydronephrosis and reflux. In other groups, the marked variation within groups prevented the use of the bladder volume on the VCUG as a proxy for voiding dysfunction.

Lower urinary tract dysfunction in childhood

Lower urinary tract syndrome is common in children. Incontinence, urinary tract infection, vesicoureteral reflux, and constipation are commonly associated with this syndrome. Examining the clinical history of the afflicted patient plays a major role in the accurate diagnosis and treatment of lower urinary tract disorder. Along with pharmacologic treatment, pelvic floor muscle retraining, biofeedback therapy, and adaptation of a healthy lifestyle are advocated for rapid recovery of patients.

Age related nocturnal urine volume and maximum voided volume in healthy children: reappraisal of International Children's Continence Society definitions

PURPOSE

We determined normal, age related reference data regarding maximum voided volume and nocturnal urine production using the same methodology as in clinical practice.

MATERIALS AND METHODS

A total of 62 girls and 86 boys without enuresis (mean +/- SD age 9.64 +/- 2.63 years, range 3 to 15) completed 4 days (2 weekends) of frequency-volume charts and 14 days of home recording of nocturnal urine production. From these recordings maximum voided volume with and without first morning void was derived for each subject. Also, average nocturnal urine volume with and without nocturia was calculated. Percentiles were produced by dividing the population into 1-year age groups.

RESULTS

Based on 2,836 daytime voids and 1,977 overnight recordings, maximum voided volume and nocturnal urine volume showed a significant linear relationship with age but not with gender. Maximum voided volume with first morning void was significantly higher than without (403 +/- 137 ml vs 281 +/- 112 ml, p <0.0001) and the 50th percentile line of maximum voided volume with first morning void was 80 to 100 ml higher than Koff's formula (30 x [age + 1] ml). Conversely the 50th percentile of maximum voided volume without first morning void was almost identical to Koff's formula. Regarding nocturnal measurements, nocturia was noted on 128 nights (6.5%) and nocturnal urine volume on nights with nocturia was significantly higher than on nights without nocturia (365 +/- 160 ml vs 248 +/- 75 ml, respectively, p <0.0001). The 97.5th nocturnal urine volume percentile line of healthy children deviated markedly from the current International Children's Continence Society definition of nocturnal polyuria, especially at low and high ages.

CONCLUSIONS

We demonstrate clearly that the universally used formula 30 x (age + 1) ml is indeed valid for a population of healthy Danish children but only if the first morning void is disregarded. Furthermore, we question the validity of the current International Children's Continence Society formula for nocturnal polyuria (nocturnal urine volume greater than 130% of maximum voided volume for age), and instead we propose the formula, nocturnal urine volume greater than 20 x (age + 9) ml.

Intractable voiding dysfunction in children with normal spinal imaging: predictors of failed conservative management

OBJECTIVES

To identify the factors that might predict which individuals ultimately fail to resolve voiding symptoms by analyzing their presenting symptoms and video-urodynamic findings. Older children with intractable voiding dysfunction and no evidence of neurologic abnormality, who are recalcitrant to medical treatment, pose a management challenge.

METHODS

The charts of neurologically normal children with intractable voiding dysfunction, who had fluorourodynamic studies and normal lumbosacral magnetic resonance imaging, were reviewed. A database was created that included the urodynamics, presenting urinary symptoms, presence of soiling or constipation, age at onset of symptoms, cystogram and bladder ultrasound findings, and treatments given. Long-term follow-up was determined from chart review (all patients) or by a mailed survey (15 patients). Patients without symptoms and off medication were defined as normal.

RESULTS

A total of 50 children met the criteria mentioned earlier in the text, presented at a mean age of 9.4 years (range, 3.8-17.3) and were followed up for a mean of 4 years (range, 1-11) from their initial urodynamic evaluation. Of them, 33 (66%) remained symptomatic and 1 (34%) normalized. A total of 31 were found to have uninhibited bladder contractions (UBCs) with daytime wetting, of which 24 (77.4%) failed to normalize (P = .037). All 9 with UBCs and detrusor-sphincter dyssynergia remained symptomatic (P = .02).

CONCLUSIONS

The majority failed to resolve their voiding symptoms. Children who presented with daytime wetting, UBC, and detrusor-sphincter dyssynergia were the most likely to remain symptomatic. Patients with these characteristics might be considered for more aggressive alternative therapies, after a period of medical management.

Bladder function in infants

The purpose with the present review was to describe what could be considered as normal urodynamic findings in neonates and infants. During the first months of life, urodynamics were characterised by small bladder capacity and high voiding pressure levels, the latter especially marked in male infants. Also dyscoordination at voiding was a common finding. However, detrusor overactivity (unstable contractions) during filling was uncommon in infants. Towards the end of infancy, findings became more in accordance with what is seen in older children. Concluding these findings concerning urodynamic pattern in early infancy high voiding pressure levels must be looked upon as normal and the same is true for intermittent increase in activity in the pelvic floor during voiding. However, instability during filling is rarely seen.