Ultrasonographic bladder measurements can replace urodynamic study for the diagnosis of non-monosymptomatic nocturnal enuresis

Could urinary nerve growth factor and bladder wall thickness predict the treatment outcome of children with overactive bladder?

Objective:

Bladder wall thickness (BWTh) measurements and Nerve Growth Factor (NGF) /creatinine (Cr) values, as noninvasive tools, were found to predict daytime voiding problems in children with overactive bladder (OAB). The goal of this research was to examine if bladder wall thickness together with urine NGF/Cr could be a clinical utility in treatment outcome of OAB in children.

Patients and Methods:

A total of 60 children with OAB, (Group 1; n=40) and healthy normal controls (Group 2; n=20), aged 6-14 years old were involved in this prospective study. Children were evaluated with detailed history and physical examination, including neurologic examination, and were asked to complete a self-reported questionnaire and a 3-day bladder diary with the aid of their parents. Uroflowmetry was performed in all cases. Urinary nerve growth factor levels were measured by the ELISA and BWTh was measured trans-abdominally by one uro-radiologist specialized in pediatric ultrasonography. Urinary NGF levels were normalized by urinary creatinine levels and compared among all subgroups. Children with OAB received urotherapy as first line treatment at least for three months. 18 children refractory to urotherapy received anticholinergic therapy defined as group 3.

Results:

The median age of the study group was 10 (range 6 to 16). After urotherapy, 22 children had similar BWTh and NGF/Cr values compared to controls. (2.75 ± 1.15; 2.40 ± 1.00 mm; p=0.86 and 1.02 ± 0.10; 0.78 ± 0.15; p=0.12, respectively). After anticholinergic treatment, BWTh levels (2.25 ± 0.90; 2.40 ± 1.00 mm; p=0.94) and NGF/Cr values (0.95 ± 0.10; 0.78 ± 0.15; p=0.42, respectively) had no significantly difference compared to controls (Group 2).

In receiver operating characteristic analysis, bladder wall thickness was found to have sensitivity of 85% and specificity of 84.2% (3,20 AUC, 913; 95 %) and NGF/Cr had sensitivity of 90% and specificity of 92.1% (1,595; AUC, 947; 95 %) in predicting treatment outcome in children with OAB.

Conclusions:

Bladder wall thickness measurements and NGF/Cr values, as noninvasive tools, could guide outcomes in the treatment of children with overactive bladder.

Role of videourodynamic study in precision diagnosis and treatment for lower urinary tract dysfunction

Lower urinary tract symptoms (LUTS) are complicated and cannot be used alone to diagnose lower urinary tract dysfunctions (LUTDs) and guide treatment. Patients with bladder outlet obstruction (BOO), impaired detrusor contractility, and hypersensitive bladder might present with voiding predominant symptoms, whereas patients with detrusor overactivity (DO), dysfunctional voiding, or BOO might also present with storage symptoms. To clearly identify the pathophysiology of LUTD, a comprehensive urodynamic study (UDS) including pressure flow and image during the storage and emptying phases, naming videourodynamic study (VUDS), is necessary. This study is especially mandatory in the diagnosis of (1) male LUTS refractory to medical treatment for benign prostatic hyperplasia, (2) female voiding dysfunction and urinary retention, (3) diagnosis of overactive bladder syndrome refractory to first-line medication, (4) management of female stress urinary incontinence and postoperative LUTS, (5) diagnosis and management of neurogenic LUTD, (6) pediatric urinary incontinence and enuresis, (7) geriatric urinary incontinence, and (8) recurrent bacterial cystitis. Although VUDS should not be used as a screening test for any LUTS, it should be considered when the initial management cannot relieve LUTS, or when invasive surgical procedure is planning to undertake for patients with refractory LUTS. VUDS should be recommended as the second-line investigation when the initial diagnosis and treatment based on the symptoms alone or noninvasive tests fail to improve LUTS.

Interrater reliability of bladder ultrasound measurements in children

INTRODUCTION

Bladder ultrasound is becoming pivotal in the management and treatment of lower urinary tract dysfunction. There is a paucity of data regarding intra-observer and interobserver reliability of bladder ultrasound, especially in children. A previous study assessed interobserver agreement for both the postvoid residual volume and measurement of the bladder dimensions in adults showing excellent agreement.

OBJECTIVE

To examine the interobserver and intra-observer reliability of bladder wall thickness, bladder urinary and postvoid residual urinary volume using ultrasound evaluated by paediatricians having different training levels.

STUDY DESIGN

Four sonographers, 3 pediatric trainees and one experienced pediatric urologist measured the full bladder volume, the voiding residual volume, and the bladder wall thickness. Each sonographer made 3 measurements of each parameter. We assessed the interobserver and intra-observer variability by using intraclass correlations (ICCs). ICCs were calculated and tested with a significance level of 5%. The interrater ICC was calculated from the mean of the three measurements of each variable (full bladder volume, postvoid residual, bladder wall thickness). ICC ≥0.75 was considered excellent. Bland-Altman plots were also used to assess the interobserver agreement.

RESULTS

Sixty children were recruited (7.3 ± 1.1 years). The interobserver ICCs for bladder volume and voiding residual volume were 0.91 (confidence interval 0.85-0.95) for both. The interobserver ICCs for the bladder wall thickness was satisfactory 0.43, with a minimum detectable difference of 2 mm. The observed values for intra-observer analysis showed an excellent (ICC ≥ 0.90) agreement between the three measurements performed by each one of the sonographers. Bland-Altman plots showed that the bias (mean difference) was -0.35 and the limits of agreement were -3.43 and 2.73 for the bladder wall thickness measurements (Figure).

DISCUSSION

The interobserver reliability for both the postvoid residual volume and full bladder volume were excellent even in operators with different levels of training, pointing out the role of bladder ultrasound in the routine clinical practice. Weaker agreement was found for the bladder wall thickness measurement. The intra-observer agreement was excellent for all the measurements.

CONCLUSION

These results showed a good reliability of urinary bladder ultrasound in children aged 7.3 ± 1.1 years as far as bladder volume measurement is concerned. Given the variability of bladder wall thickness, a standardized methodology is desirable to increase its reliability.

'Frequently recurring' nocturnal polyuria is predictive of response to desmopressin in monosymptomatic nocturnal enuresis in childhood

INTRODUCTION

The nocturnal polyuria is considered a significant predictive value for response to desmopressin. The cutoff value useful to define nocturnal polyuria is still a matter of debate. Moreover, it is current notion that maximal voided volume (MVV) could be used as a predictor for desmopressin response.

OBJECTIVE

The objective of this study was to assess the impact of different definitions of nocturnal polyuria (and of its frequency) and MVV in predicting the response to desmopressin.

STUDY DESIGN

A total of 103 patients with frequent monosymptomatic nocturnal enuresis (≥4 wet nights/week) were enrolled. A bladder diary over a 4-day period was collected. The MVV was defined as the highest micturition volume detected at bladder diary. Nocturnal diuresis was measured in 5 wet nights. Then, patients were administered with 120 mcg of sublingual desmopressin. After 2 months, if there was no complete response, the dose was increased to 240 mcg. Nocturnal polyuria was defined as follows: 1.Definition 1: nocturnal urine production >130% of the expected bladder capacity (EBC). 2. Definition 2: >100% EBC. 3. Definition 3: > 20×(age + 9) mL. The primary outcome was 'response to desmopressin' after 3 months of treatment.

RESULTS

Fifty-three patients responded to desmopressin. Comparing the responses to desmopressin on the basis of the three definitions of nocturnal polyuria, no significant difference was found. There was no cutoff value of nocturnal polyuria expressed as %EBC useful in providing a significant receiver-operating characteristic (ROC) curve. The area under the ROC curve for MVV expressed as %EBC was 0.67 (95% confidence interval [CI], 0.54-0.80; p = 0.01). A MVV >103.1% of EBC had 78.8% (95% CI, 61.1-91.0) sensitivity and 47.5% (95% CI, 31.5-63.9) specificity for predicting response to desmopressin. Among the patients with nocturnal polyuria according to definition 1, a higher percentage of subjects with nocturnal polyuria in 4 out of 5 or 5 out of 5 nights responded to desmopressin, compared with other patients. Patients presenting with nocturnal polyuria according to definition 3 in 5 out of 5 nights showed a 100% of response to desmopressin. At multivariate analysis, the only significant odds ratio (OR) to respond to desmopressin was that of patients with nocturnal polyuria according to definition 1 in >3 nights (OR = 7.1, 95% CI, 1.3-40.3).

DISCUSSION AND CONCLUSIONS

The presence or absence of nocturnal polyuria-according to all three definitions-in at least one night was not effective in predicting the response to desmopressin. Predictors of desmopressin response were nocturnal polyuria in >3 out of 5 wet nights according to definition 1 and in 5 out of 5 wet nights according to definition 3.

Clinical features of, and association of bladder ultrasound and uroflowmetry with, overactive bladder recovery period in children

BACKGROUND

Overactive bladder (OAB) is a symptomatic syndrome defined by urinary urgency, usually accompanied by increased urination frequency and nocturia, with or without urinary incontinence. The prevalence of pediatric OAB in 5-13 year olds is as high as 16.6%, but the pathophysiology and epidemiology have not been sufficiently elucidated.

METHODS

We retrospectively reviewed medical records in 117 children with OAB aged between 5 and 15 years during the years 2012-2016. At initial presentation, abdominal ultrasound and uroflowmetry were performed, and behavioral modifications, such as timed voiding, and constipation therapy were initiated. If there was no response after 4 weeks, antimuscarinic treatment was added. We evaluated the clinical features of OAB and factors related to the recovery period, which was defined as the period from the start of behavioral modifications to cure.

RESULTS

The average recovery period was 11.9 ± 9.73 months. There was no significant difference in the recovery period according to age, gender, percentage of urination frequency, nocturnal enuresis, or constipation. The recovery period was significantly shorter in the group with bladder wall thickness ≥5 mm than with bladder wall thickness <5 mm. Children with a tower-shaped curve on uroflowmetry had a significantly shorter recovery period than those with a bell-shaped curve.

CONCLUSIONS

Bladder wall thickness and uroflow curve shape are related to the recovery period of pediatric OAB.

Can urinary nerve growth factor and bladder wall thickness correlation in children have a potential role to predict the outcome of non-monosymptomatic nocturnal enuresis?

INTRODUCTION

Measurement of bladder wall thickness (BWTh) by ultrasound has been introduced as a new and promising technique to assess bladder dysfunction, and increased levels of nerve growth factor have also been reported in the bladder tissue and urine of patients with sensory urgency and detrusor overactivity (DO).

OBJECTIVE

In this study we aimed to generate a clinically useful tool with urinary nerve growth factor levels and ultrasonographic BWTh to find possible pathogenetic clues and prognostic indicators as guides for the choice of therapy of non-monosymptomatic nocturnal enuresis.

METHODS

A total of 110 children, aged 6-16 years old, were involved in this prospective study. Group 1 consisted of children with non-monosymptomatic nocturnal enuresis (n = 40), Group 2 of children with monosymptomatic nocturnal enuresis (n = 40) and Group 3 of children with healthy normal controls (n = 30). Children were evaluated with detailed history and physical examination, including neurologic examination; they were asked to complete a self-reported questionnaire and a 3-day bladder diary with the aid of their parents. The number of wet nights, the number of voids per night, the presence of daytime voiding symptoms (urgency, urge incontinence, incontinence, holding maneuvers, frequency), fluid intake, and any history of urinary tract infections (UTIs) were recorded. Monosymptomatic nocturnal enuresis and non-monosymptomatic nocturnal enuresis diagnosis was made using the International Children's Continence Society definition. Urinary nerve growth factor levels were measured by enzyme-linked immunosorbent assay and BWTh was measured transabdominally by a uroradiologist who specialized in pediatric ultrasonography. Urinary nerve growth factor levels were normalized by urinary creatinine levels and compared in all subgroups.

RESULTS

The mean age of the study group was 9.6 (range 6-16) years. The mean BWTh was significantly increased in Group 1 compared with Group 2 (4.33 ± 1.12 mm, 2.33 ± 1.03 mm; p < 0.001) and healthy controls (4.33 ± 1.12 mm, 1.86 ± 0.57 mm; p < 0.001, respectively). Urinary levels of nerve growth factor corrected to urine creatinine (NGF/Cr) significantly increased in Group 1 with to Group 2 (2.75 ± 1.15 vs. 0.58 ± 0.15; p < 0.001) and controls (2.75 ± 1.15 vs.0.28 ± 0.10; p < 0.001, respectively). In receiver operating characteristic analysis, BWTh was found to have sensitivity of 95% and specificity of 85.7% (3.00 area under the curve [AUC] 0.937; 95%) and NGF/Cr had sensitivity of 97.5% and specificity of 98.6% (0.885; AUC, 999; 95%) in predicting lower urinary tract symptoms (LUTS) for non-monosymptomatic nocturnal enuresis (NMNE) (Figure).

DISCUSSION

In our study we have investigated that BWTh together with urinary NGF levels normalized to the concentration of urinary creatinine (NGF/Cr) may predict daytime voiding problems in children with primary nocturnal enuresis (PNE). The main basis of this study is previous findings which demonstrated that ultrasonography (US)-based measurement of BWTh is a useful diagnostic parameter for LUTS in children, and that increased levels of NGF in bladder tissue and urine such as sensory urgency, DO, and overactive bladder (OAB) was indicated by clinical and experimental studies. The present study demonstrated that urinary NGF/Cr levels and BWTh measurements were significantly increased in patients with NMNE with daytime urinary symptoms (urgency, urge-incontinence, incontinence, frequency) showing symptoms of an OAB than controls and MNE.

CONCLUSION

BWTh measurements and NGF/Cr values, as non-invasive tools, may guide therapy and improve outcomes in the treatment of children with NMNE. Further studies including a larger number of patients would be of great interest.

Lower Urinary Tract Urological Abnormalities and Urodynamic Findings of Physiological Urinary Incontinence Versus Non-mono Symptomatic Nocturnal Enuresis in Children

BACKGROUND

Although 98% of children attain daytime bladder control by three years of age, urinary incontinence is regarded physiological up to the fifth year of life.

OBJECTIVES

This study aimed to assess whether lower urinary tract urological abnormalities and abnormal urodynamic findings are infrequent in children with physiological urinary incontinence in contrast to those with non-monosymptomatic nocturnal enuresis (NMNE).

PATIENTS AND METHODS

During a three-year period (2007-2009), 66 neurologically normal children including 51 children (34 girls, 17 boys) older than five years of age with NMNE and intermittent daytime incontinence, and 15 children with physiological urinary incontinence (eight girls and seven boys) aged four to five years of age without any known urological abnormalities were enrolled in the study. Patients with neurologic deficits or known urological anomalies were excluded from the study. Kidney-bladder ultrasonography, voiding cystourethrography (VCUG), and urodynamic studies were performed to evaluate the anatomy of urinary tract and bladder function.

RESULTS

Urinary tract infection was found in 23 (34.8%) children, 17 (33.3%) and 6 (40%) patients with NMNE and physiological urinary incontinence, respectively. Out of 48 patients who underwent VCUG, vesicoureteral reflux (VUR) was found in seven and eight children younger and older than five years of age, respectively. Abnormal urodynamic findings were reported in 5 (62.5%) of eight children younger than five-year-old, and 14 (63.6%) of 22 patients older than 5-year-old.

CONCLUSIONS

VUR might be more frequent in children with physiological urinary incontinence than the normal population, and might be as common as NMNE with intermittent daytime incontinence.

Ultrasound bladder wall thickness measurement in diagnosis of recurrent urinary tract infections and cystitis cystica in prepubertal girls

OBJECTIVE

To evaluate urinary bladder wall thickness (BWT) assessed by ultrasound as a diagnostic tool for cystitis cystica.

PATIENTS AND METHODS

This was a 9-year prospective study comprising 120 prepubertal girls. Sixty subjects of whom half underwent cystoscopy represented cases while the other 60 (those with a single urinary tract infection and healthy subjects) represented controls.

RESULTS

Based on receiver operating characteristics (ROC) analysis, BWT discriminated very well between cases and controls with area under the ROC curve close to 1.0. At the optimum cut-off defined at 3.9 mm, negative predictive value (NPV) was 100% leaving no probability of cystic cystitis with BWT <3.9 mm. Positive predictive value (PPV) was also very high (95.2%), indicating only around 4.82% probability of no cystic cystitis in patients with BWT values ≥3.9 mm. BWT could also distinguish between healthy subjects and those with a cured single urinary tract infection, although discriminatory properties were moderate (area under ROC 86.7%, PPV 78.8%, NPV 85.2%).

CONCLUSION

Ultrasound mucosal bladder wall measurement is a non-invasive, simple and quite reliable method in diagnosis of cystitis cystica in prepubertal girls with recurrent urinary tract infections.

Bladder wall thickness and urodynamic correlation in children with primary nocturnal enuresis

OBJECTIVE

To investigate the correlations between ultrasonographic bladder wall thickness (BWTh) and urodynamic study (UDS) findings and estimate the diagnostic value of BWTh for prediction of DO in children with monosymptomatic and non-monosymptomatic primary nocturnal enuresis (PNE).

PATIENTS AND METHODS

Ultrasound measurements (US) and UDS were performed on a total of 100 children, 50 consecutive boys and 50 consecutive girls, 6-14 years old, with monosymptomatic PNE (group 1, n = 75), and non-monosymptomatic PNE (group 2, n = 25). The US Protocol was specially designed for the evaluation of BWTh. All children underwent urodynamic studies for detailed assessment of any underlying bladder overactivity. Findings were compared between the two groups of patients.

RESULTS

The mean BWTh was increased in the group 2 compared to the group 1 (mean ± SD = 2.4 ± 0.41 mm, mean ± SD = 1.52 ± 0.18 mm respectively, p < 0.05). Detrusor overactivity (DO) occurred in 23/75 (30.5%) children of the group 1 and in 17/25 (68%) children of the group 2 (p < 0.05). Comparing the BWTh between the two groups of patients and the UDS findings, it was found that BWTh was significantly correlated with DO(r = 0.92 and p < 0.001), children with DO presented significantly increased BWTh compared to those without (mean ± SD = 2.1 ± 0.4 mm, mean ± SD = 1.5 ± 0.4 mm respectively, p < 0.05) and the maximum amplitude of DO occurred in 20 children who had non-monosymptomatic PNE.

CONCLUSIONS

We suggest that BWTh could be applied as a screening tool to identify the cases of DO between the children with PNE. Children with non-monosymptomatic PNE presented increased BWTh and higher percentages of DO.