Videourodynamic Findings in Young Infants With Severe Primary Reflux

Evaluation of the results of urodynamic studies in patients with vesicoureteral reflux

BACKGROUND

To investigate urodynamic abnormalities associated with vesicoureteral reflux (VUR) in toilet-trained children.

METHODS

The data of 157 children who were diagnosed with vesicoureteral reflux and referred to our hospital between 2013 and 2022 were retrospectively examined. The urodynamic parameters were analyzed and correlated with age, gender, lower urinary tract symptoms (LUTS), reflux severity, and laterality.

RESULTS

Overall, 131 (83.4%) patients had abnormal urodynamic findings with a male-to-female ratio of 1:1.4. The most common pathological finding was detrusor overactivity (DO), identified in 101 (64.3%) patients, followed by dysfunctional voiding (DV) in 74 (50.3%) patients. Children with VUR grades II and III exhibited a greater percentage of abnormal urodynamic findings than children with grades IV and V. The prevalence of DO was higher in children younger than 10 years old with unilateral and lower-grade VURs. DV was more frequent in children older than 10 years, with bilateral VUR, and higher grade VUR. The prevalence of LUTS, bowel and bladder dysfunction (BBD), and urinary tract infection (UTI) was higher among children with abnormal urodynamic findings.

CONCLUSIONS

Children with VUR have a high incidence of urodynamic disorders. Urodynamic dysfunction may contribute to the pathogenesis of VUR, especially in mild cases.

The impact of reflux pressure on renal scarring in children with sterile vesicoureteral reflux

INTRODUCTION

Vesicoureteral reflux (VUR) is a complex disease as patient spectrum is variable. Some cases struggle with recurrent febrile urinary tract infections (UTI) and end-up with renal scars despite intervention. While others suffer no clinical problems and need no treatment. The detrimental effect of VUR on kidneys depends on many factors like grade of reflux, detrusor pressure, and presence of voiding dysfunction. The adverse effects of sterile VUR on kidneys is still under discussion. Thus, we assessed the impact of detrusor pressure at VUR onset on renal scarring in children with sterile reflux.

MATERIALS AND METHODS

We retrospectively reviewed the five years follow-up data of 38 children who had unilateral VUR without UTI under treatment. No febrile or afebrile UTIs were detected during the follow-up in any children. All children were assessed with annual video-urodynamics and renal scintigraphy for five consecutive years. The detrusor pressure at VUR onset, grade of VUR, presence of involuntary detrusor contractions, bladder capacity and the presence of renal scaring were recorded. All VURs were recorded during the voiding phase and children with VUR during the filling phase were excluded from the study.

RESULTS

In the first line of video-urodynamic studies, the mean detrusor pressure at VUR onset was 24.3 ± 14.8 cm/H2O (median 34.5 cm/H2O, min: 6 - max: 47). There was no relation between boys and girls regarding median detrusor pressure at VUR onset (p = 0.356). Eventually, 22 (57.9%) children developed renal scars and ended up with surgery. There was no relation between scar development and age at first presentation (p = 0.888) The cut-off value for detrusor pressure at VUR onset was noted as 26 cm/H2O (AUC: 0.849 [p < 0.01], Figure). In children who developed renal scars eventually, the median detrusor pressure at VUR onset was significantly higher (p < 0.01).

DISCUSSION

The detrimental effect of VUR on kidneys is associated with recurrent infections, bladder dysfunction, and detrusor pressure. Dispute over risk of renal scarring in patients with sterile VUR still continues.

CONCLUSION

Children in whom VUR start at higher voiding pressures suffer more renal scars. The threshold of voiding detrusor pressure for risky patients is identified as 26 cm/H2O. It is true that patients suffering recurrent febrile UTIs have higher risk of developing renal scarring. However, the impact of sterile reflux should not be underestimated, since renal scars due to sterile reflux may develop in patients under antibiotic prophylaxis.

The accuracy of cystography under general anesthesia in children with vesicoureteral reflux

PURPOSE

To examine the accuracy of cystography under general anesthesia in children with vesicoureteral reflux (VUR).

MATERIALS AND METHODS

A prospective study of children who had VUR on cystography without general anesthesia (i.e., the gold-standard), and who are candidates for endoscopic VUR repair surgery. All children subsequently underwent a cystography under general anesthesia before injection using standardized method, which was compared to the gold-standard cystography. χ² and Mann-Whitney U tests were used to compare proportions and medians between groups.

RESULTS

Between 2017 and 2021, 126 renal units in 13 boys and 50 girls were included. Median age was 3.4 years (interquartile range [IQR] 1.5-6.5). Median time from cystography without to cystography with general anesthesia was 3.8 months (IQR 2.7-6). Of the 126 renal units, 96 had VUR on cystography without general anesthesia. On dichotomous analysis (no VUR vs. any VUR) sensitivity, specificity, negative and positive predictive values of cystography under general anesthesia were 47% (45/96), 87% (26/30), 34% (26/77) and 92% (45/49), respectively. Accuracy was 56.3%; Cohen's Kappa coefficient was 0.22, indicating poor agreement. In subgroup analysis, the sensitivity of cystography under general anesthesia was significantly lower in primary VUR (20% vs. 55% in secondary VUR, p = 0.01) and active VUR (14% vs. 52% in passive VUR, p = 0.008).

CONCLUSION

Cystography under general anesthesia was poorly correlated to cystography performed while the child was awake or lightly sedated. Clinical decision relying on this cystography is questionable.

International Consultation on Incontinence 2016; Executive summary: Urodynamic testing

AIMS

The International Consultation on Incontinence has published an update of the recommendations for the diagnosis and management of urine incontinence (ICI2016). This manuscript summarizes the consultations committee-recommendations with regard to urodynamic assessment.

METHODS

Expert consensus on the basis of structured evidence assessment has been the basis of the consultations publication and has been summarized by the committee for this manuscript.

RESULTS

Patients that are not satisfied with their initial management on the basis of their reported signs and symptoms of urinary incontinence, as well as all patients with neurological abnormalities that are potentially relevant for the function of the lower urinary tract, may very likely profit from objective diagnosis and staging and grading of their dysfunction, with urodynamic testing, regardless their age, vulnerability and/or comorbidities. The principles and technical innovations as well as the principal recommendations for the utilization of (invasive) urodynamic assessment for women, men, children, and vulnerable elderly, with or without neurogenic lower urinary tract dysfunction with urinary incontinence are provided in this abbreviated ICI recommendations-document.

CONCLUSIONS

The ICI2016 committee on urodynamics presents an executive summary of the most important reasons and recommendations for the use of urodynamic investigations for patients with urinary incontinence.

Pathophysiological and Therapeutic Considerations for Non-Neurogenic Lower Urinary Tract Dysfunction in Children

Non-neurogenic lower urinary tract dysfunction (LUTD) in children is very common in clinical practice and is important as an underlying cause of lower urinary tract symptoms, urinary tract infection and vesicoureteral reflux in affected children. LUTD in children is caused by multiple factors and might be related with a delay in functional maturation of the lower urinary tract. Behavioral and psychological problems often co-exist in children with LUTD and bowel dysfunction. Recent findings in functional brain imaging suggest that bladder bowel dysfunction and behavioral and psychiatric disorders in children might share common pathophysiological factors in the brain. Children with suspected LUTD should be evaluated properly by detailed history taking, validated questionnaire on voiding and defecation, voiding and bowel diary, urinalysis, screening ultrasound, uroflowmetry and post-void residual measurement. Invasive urodynamic study such as videourodynamics should be reserved for children in whom standard treatment fails. Initial treatment of non-neurogenic LUTD is standard urotherapy comprising education of the child and family, regular optimal voiding regimens and bowel programs. Pelvic floor muscle awareness, biofeedback and neuromodulation can be used as a supplementary purpose. Antimuscarinics and α-blockers are safely used for overactive bladder and dysfunctional voiding, respectively. For refractory cases, botulinum toxin A injection is a viable treatment option. Prudent use of urotherapy and pharmacotherapy for non-neurogenic LUTD should have a better chance to cure various problems and improve self-esteem and quality of life in affected children.

Radiological bladder characteristics in VCU for young children with high-grade VUR

OBJECTIVES

It has been suggested that infants with dilating vesicoureteral reflux (VUR) often have lower urinary tract (LUT) dysfunction. Signs such as high voiding pressure levels, low bladder capacity and dyscoordination at voiding have previously been thought to be indicative of dysfunction. However, these findings have also been recognised in healthy infants and are, thus, not specific to dysfunction in this age group. The urodynamic findings of interest for LUT dysfunction in children with high-grade VUR have been shown to be high bladder capacity with incomplete emptying, and often with overactivity during filling. Because the bladders in children with VUR are often only investigated with voiding cystourethrography (VCUG) and not urodynamics, the question has arisen as to whether some of the urodynamic findings indicating dysfunction can be recognised as radiological signs. The aim of the present study was to evaluate whether cystometric signs of LUT dysfunction in infants with high-grade VUR could be recognised in VCUG.

MATERIALS AND METHODS

One hundred and fifteen infants (80 boys) with Grades III-V VUR were included and investigated repeatedly with videocystometry (VCM) at a median age 6, 21 and 39 months. The sign looked for in the VCUG was bladder size (large, normal or small), according to the chosen levels in the bony pelvis. To validate the chosen levels for the different bladder sizes, bladder capacity data from a longitudinal study in healthy children were used. In addition, abnormalities in bladder wall/form and filling of the posterior urethra without voiding, as signs of bladder overactivity and detrusor-sphincter dyscoordination, were evaluated.

RESULTS

Bladder size was estimated on VCUG as large, normal or small, according to pelvic landmarks. Large bladder size was mainly seen at the second and third evaluations (64% and 46%), whereas small capacity was mainly seen during the first year (33%). Corresponding cystometric capacities (ml) showed a significant difference between the groups of small, normal and large bladder size. The cystometric capacities of large and small bladder size were also compared with bladder capacity in healthy controls, where large had significantly higher bladder capacity versus age (P = 0.0001) and small had significantly lower (P = 0.011) bladder capacity versus age than in the healthy controls. Bladder shape/wall pathology was mainly seen during the first year (42%), combined with small capacity, and correlated to overactive contractions during filling. Moreover, filling of the posterior urethra without voiding, indicating detrusor/sphincter dyscoordination at voiding, was quite common during the first year (33%), and then successively decreased.

CONCLUSIONS

The clinical implication from this study of small children with high-grade VUR was that a large bladder on VCUG was synonymous with a high-capacity bladder. According to earlier studies, this is a sign of LUT dysfunction in this age group and should therefore be an indicator for additional studies of bladder function. Overactive contractions could also be recognised in VCUG, but only at the infant evaluation, which should also be regarded as an indicator of LUT dysfunction. All other bladder VCUG signs mainly seen during early infancy were signs of immature bladder function and not a result of VUR dysfunction.

Best practice in the assessment of bladder function in infants

The purpose of this article is to review normal developmental bladder physiology in infants and bladder dysfunction in conditions such as neurogenic bladder, posterior urethral valves and high grade vesicoureteric reflux. We contrast the classical concept that bladder function in nontoilet-trained children is thought to be 'reflexive' or 'uninhibited', with the results of more recent research showing that infants most commonly have a stable detrusor. The infant bladder is physiologically distinct from the state seen in older children or adults. The voiding pattern of the infant is characterized by an interrupted voiding stream due to lack of proper urinary sphincter relaxation during voiding. This is called physiologic detrusor sphincter dyscoordination and is different from the pathologic 'detrusor sphincter dyssynergy' seen in patients with neurogenic bladder. Urodynamic abnormalities in neonates born with spina bifida are common and depend on the level and severity of the spinal cord malformation. Upper neuron lesions most commonly lead to an overactive bladder with or without detrusor sphincter dyssynergy while a lower neuron lesion is associated with an acontractile detrusor with possible denervation of the external urinary sphincter. In infants with neurogenic bladder, the role of 'early prophylactic treatment (clean intermittent catheterization and anticholinergics)' versus initial 'watchful waiting and treatment as needed' is still controversial and needs more research. Many urodynamic-based interventions have been suggested in patients with posterior urethral valves and are currently under scrutiny, but their impact on the long-term outcome of the upper and lower urinary tract is still unknown. Cumulative data suggest that there is no benefit to early intervention regarding bladder function in infants with high-grade vesicoureteric reflux.

Predict the spontaneous resolution of vesicoureteral reflux by direct radionuclide cystography

OBJECTIVES

To evaluate the prognostic value of initial direct radionuclide cystography (DRC) for spontaneous resolution of vesicoureteral reflux (VUR).

METHODS

Fifty-one children with initial diagnosis and 1-6 years' follow-up of VUR by DRC were enrolled in this study. VUR was graded according to the anatomic grading as (1) mild reflux corresponding to tracer just in ureter, (2) moderate reflux with accumulation of activity in a non-dilated collecting system and ureter, and (3) severe reflux equated with a dilated ureter and collecting system. The severity of VUR was also expressed according to the functional classification as (1) transient reflux, which occurred at filling or voiding phase only and (2) persistent reflux, present in both filling and voiding phases.

RESULTS

Twenty-nine of the 51 children had unilateral VUR, and the other 22 had bilateral VUR. In the total of 73 refluxing ureters, there were 12 mild, 49 moderate and 12 severe VUR according to anatomic grading, and 30 transient and 43 persistent VUR according to the functional grading. After follow-up, resolution of VUR was found in 92% (11/12) of mild, 59% (29/49) of moderate and 25% (3/12) of severe VUR (P=.04, mild vs. moderate; P=.003, mild vs. severe). Eighty percent (24/30) of transient and 44% (19/43) of persistent reflux showed spontaneous resolution (P=.003).

CONCLUSIONS

DRC allows anatomic and functional classification of VUR. It is an ideal method for the diagnosis, staging and follow-up of VUR, and provides valuable information to predict the patient's outcome.

Is there any role for urodynamic study in children with high-grade vesicoureteral reflux?

OBJECTIVE

To determine the clinical symptoms and urodynamic characteristics among children with primary high-grade vesicoureteral reflux (VUR).

MATERIALS AND METHODS

We prospectively studied clinical symptoms and urodynamic parameters in 147 consecutive patients ≤ 12 years old with idiopathic high-grade VUR referred to our hospital.

RESULTS

Of 147 patients with high-grade VUR, 139 cases with mean age of 5.3 years met our inclusion criteria (88.5% females, 11.5% males). The most common symptom was recurrent urinary tract infection (57%) and urgency (59%) followed by enuresis (31.6%) and frequency (26.6%). Normal urodynamic findings were observed in 23% of patients. Overactive bladder (74%), high-end filling pressure (72.7%), low-compliance bladder (56%), and low bladder capacity (51%) were the most common urodynamic reports in this study. Other urodynamic findings were underactive bladder (1.5%), hypersensitive bladder (1.5%), hyposensitive bladder (3%), and high capacity bladder (2.2%).

CONCLUSION

Proper management of VUR is very important because of its harmful potential effects on kidney function in children. With regard to the issue that most children with grade III and higher VUR had overactive bladder, high-end filling pressure, and other urodynamic disorders in their urodynamic study, it seems that these urodynamic disorders could be the basic cause of reflux.

Renal parenchyma abnormalities in infants with dilating vesicoureteral reflux: relation to reflux severity and pressure at onset

PURPOSE

We used (99m)technetium dimercapto-succinic acid scans in infants to determine the relation between renal deformities and severity of primary dilating reflux. We also used videourodynamics to analyze the association between detrusor pressure at onset of reflux and degree of renal changes.

MATERIALS AND METHODS

A total of 20 patients (15 males) 0.10 to 1.3 years old (median 0.75) with grade III to V reflux underwent conventional filling videourodynamics. (99m)Technetium dimercapto-succinic acid scans were done 6 months after the last febrile urinary tract infection (median age 0.58 years).

RESULTS

Nine males and 1 female had bilateral refluxing ureters, and 10 patients had unilateral reflux (grade III in 10, IV in 11 and V in 9). Among the 30 refluxing ureters renal changes were present in 19 kidneys (63%). Prevalence of renal changes according to reflux grade III, IV and V was 40%, 63% and 89%, respectively (p <0.02). Reflux occurred in 13 patients (21 ureters) with detrusor pressure less than 10 cm water and in 7 (9) at 30 to 70 cm water (median 39.5). Renal changes were significantly more common in low pressure, low volume refluxing ureters (84.6%) compared to ureters refluxing at higher volumes and low pressure (37.5%, p <0.02). At higher pressure reflux renal deformities occurred in 55.5% of refluxing ureters (5 of 9). Five patients had renal function impairment (mean creatinine for age 0.92 mg/dl, range 0.60 to 1.53).

CONCLUSIONS

High grade reflux and reflux occurring in the first half of bladder filling at low pressure are risk factors for renal changes in this cohort of infants.

The nature of high-pressure voiding in small boys and its relation with the influence of a transurethral catheter

AIMS

To disclose the nature of the high-pressure voiding observed in small boys and to determine the influence of a transurethral catheter on voiding urodynamic parameters and reproducibility of these parameters.

MATERIALS AND METHODS

Video-urodynamic studies (V-UDSs) were repeated twice in a single session using two different sized, 18G (Ø1.15 mm) and 7.4Fr (Ø2.50 mm), catheters in 9 boys aged 7.3 months (2-17) and compared with the maximum voiding detrusor pressure (P(det max)) values. Separately, in 20 boys aged 8.9 (1-34) months, V-UDSs using an 18G catheter were repeated twice, and fluoroscopic images and UDS were continuously recorded during the whole voiding phase and analyzed.

RESULTS

There was no significant difference between the mean P(det max) measured by the 18G and 7.4Fr catheters (102.0 +/- 22.5 vs. 94.7 +/- 25.6 cmH(2)O, P = 0.42). Intermittent interruptions of the urinary stream due to detrusor-sphincter dyscoordination were observed in 92.5% (37/40) of voiding cycles. The true maximum voiding detrusor pressure (T-P(det max)), the maximum detrusor pressure recorded only when the urinary stream was actually detected, on the first and second voiding cycles were 86.9 +/- 30.3 and 89.0 +/- 31.7 cmH(2)O, respectively. The mean difference between P(det max) and T-P(det max) was 5.6 +/- 11.4 cmH(2)O. The minimum detrusor pressure during voiding (33.6 +/- 18.4 and 30.8 +/- 16.3 cmH(2)O), the opening detrusor pressure and the number of stream interruptions were reproducible.

CONCLUSIONS

Small boys commonly void intermittently with a high detrusor pressure, which may be mainly due to detrusor-sphincter dyscoordination rather than the outflow obstruction caused by a transurethral catheter.

Reference Ranges for Cystographic Bladder Capacity in Children—With Special Attention to Vesicoureteral Reflux

PURPOSE

Linear correlations for cystometric/cystographic bladder capacity with age universally serve as clinical yardsticks in pediatric urology and nephrology. However, these correlations do not account for growth or the range in values, as the relation of cystometric/cystographic bladder capacity with age is nonlinear. Also, vesicoureteral reflux might influence the size of cystometric/cystographic bladder capacity, since small and large bladder capacities have been reported in conjunction with reflux. We decided to use the data sets of the International Reflux Study in Children to construct full reference ranges for cystometric/cystographic bladder capacity and age, for comparison with existing reference ranges in normal children, and to study the relation between bladder capacity and refluxing volume.

MATERIALS AND METHODS

In the International Reflux Study in Children 386 patients with grade III or IV vesicoureteral reflux were followed with isotope cystography for 10 years. To follow the grade of reflux, x-ray cystography was also used at 60-month intervals. The 386 children, who were 1 month to 12 years old, were randomized into 2 groups-those undergoing surgery and those receiving medical treatment. For both groups data were available on cystometric/cystographic bladder capacity, refluxing volume, reflux grade and reflux outcome.

RESULTS

The distribution of cystometric/cystographic bladder capacity vs age is logarithmic, with a wide range between the 5th and 95th percentiles, and a clear nonlinear relation between bladder capacity and age (p < 0.001). Gender has no influence on cystometric/cystographic bladder capacity. No difference in bladder capacity exists between persistence or resolution of vesicoureteral reflux (p < 0.78), between grade III and grade IV reflux (p < 0.94), or between unilateral and bilateral reflux (p < 0.74). Thus, refluxing volume correlated only with reflux grade, not with cystometric/cystographic bladder capacity or age.

CONCLUSIONS

With or without vesicoureteral reflux values for cystometric/cystographic bladder capacity range widely in children, and correlate logarithmically with age. For clinical decisions the full reference range for age, flanked by the 5th and 95th percentiles, should be used to assess individual values for cystometric/cystographic bladder capacity, rather than linear functions.