Renal morphology and function from childhood to adulthood in Turner syndrome.

BACKGROUND: Turner syndrome (TS) is a chromosomal disorder with various complications, including congenital anomaly of the kidney and urinary tract (CAKUT). However, its renal function remains poorly known. Therefore, this study aimed to evaluate renal function in TS of various ages from childhood to adulthood. METHODS: We retrospectively analyzed 63 patients with TS who visited our hospital between 1989 and 2020, examined their renal morphology, and analyzed renal function by calculating the estimated glomerular filtration rate (eGFR) using formulas applicable for Japanese populations. RESULTS: Renal morphological abnormality was observed in 22 cases (35.0%) (horseshoe kidney, 7 [11.1%]; hydronephrosis, 11 [17.5%]; duplex collecting system, 3 [4.8%]; and single unilateral kidney, 1 [1.6%]). We evaluated the eGFR of 47 subjects aged 2.8-39.3 years and classified them into Group 1 (with CAKUT, n = 15) and Group 2 (without CAKUT, n = 32). The eGFR at the first visit and the final follow-up was not statistically different between these groups. In Group 1 with CAKUT, the eGFR was not significantly different between that at the first visit and that at the final follow-up (p = 0.21). During the observation period (median, 7.9 years), the eGFR of all individuals in both groups gradually decreased with age, but did not fall < 60 mL/min/1.73 m2, which defines chronic kidney disease (CKD). CONCLUSIONS: The renal function of TS remained normal in all cases during our investigation period, and no one developed CKD by the age of 40 years.

SARS-CoV-2 infection and recurrence of anti-glomerular basement disease: a case report.

BACKGROUND: Anti-glomerular basement membrane disease (GBM) disease is a rare autoimmune disease causing rapidly progressive glomerulonephritis and pulmonary haemorrhage. Recently, an association between COVID-19 and anti-glomerular basement membrane (anti-GBM) disease has been proposed. We report on a patient with recurrence of anti-GBM disease after SARS-CoV-2 infection. CASE PRESENTATION: The 31-year-old woman had a past medical history of anti-GBM disease, first diagnosed 11 years ago, and a first relapse 5 years ago. She was admitted with severe dyspnoea, haemoptysis, pulmonary infiltrates and acute on chronic kidney injury. A SARS-CoV-2 PCR was positive with a high cycle threshold. Anti-GBM autoantibodies were undetectable. A kidney biopsy revealed necrotising crescentic glomerulonephritis with linear deposits of IgG, IgM and C3 along the glomerular basement membrane, confirming a recurrence of anti-GBM disease. She was treated with steroids, plasma exchange and two doses of rituximab. Pulmonary disease resolved, but the patient remained dialysis-dependent. We propose that pulmonary involvement of COVID-19 caused exposure of alveolar basement membranes leading to the production of high avidity autoantibodies by long-lived plasma cells, resulting in severe pulmonary renal syndrome. CONCLUSION: Our case supports the assumption of a possible association between COVID-19 and anti-GBM disease.

Contrast-enhanced voiding urosonography in the assessment of vesical-ureteral reflux: the time has come.

Vesicoureteral reflux (VUR) is a pathological condition contradistinguished by monolateral or bilateral retrograde flow of urine from the bladder to the ureter and to the kidney. If not properly recognized and treated, VUR can potentially be associated to several complications such as recurrent infections and possible secondary scars with Chronic Kidney Disease (CKD). Furthermore, it represents an important risk factor for nephrovascular hypertension. During the last 20 years, the diagnostic approach to this entity has passed through several, drastic changes: indeed, since its introduction in 1994 contrast-enhanced voiding urosonography (ceVUS) has gradually accompanied the voiding cystourethrography (VCUG) as alternative imaging technique for the diagnosis and staging of VUR. Despite a large number of papers has strongly encouraged its use in clinical practice, due to the lack of ionizing radiations and its high sensitivity rate, to date almost all the guidelines only include the VCUG for VUR diagnosis. The introduction of technologically advanced US software and the approval of the intravesical administration of ultrasound contrast agents by the Food and Drug Administration (FDA) and by the European Medicine Agency (EMA) have to induce the Scientific Community to a deep revaluation of the role of ceVUS in the diagnosis and follow-up of VUR: urosonography might extensively replace VCUG as the reference method, reserving to cystourethrography a role in the most complex anatomic settings for pre-surgical evaluation.

Effect of Early Oxybutynin Treatment on Posterior Urethral Valve Outcomes in Infants: A Randomized Controlled Trial.

PURPOSE: We studied the effect of oxybutynin on bladder and upper urinary tract outcomes in infants following posterior urethral valve ablation. MATERIALS AND METHODS: Patients younger than 12 months old who had undergone primary endoscopic valve ablation for posterior urethral valves were screened for eligibility. Patients who had undergone urinary diversion or had other conditions that could affect lower urinary tract function were excluded. Study patients were randomized to either oxybutynin (0.2 mg/kg 3 times daily) until toilet training or active observation. The study end points were serum creatinine, estimated glomerular filtration rate, hydronephrosis improvement, vesicoureteral reflux resolution, febrile urinary tract infection and toilet training. RESULTS: A total of 49 infants (24 receiving oxybutynin and 25 undergoing observation) were enrolled between December 2013 and September 2015 and completed at least 1 year of followup. Oxybutynin was discontinued before toilet training in 5 patients due to facial flushing in 2, bladder and upper tract dilatation in 2, and cognitive changes in 1. After a median followup of 44.2 months (range 12 to 57.6) median serum creatinine and estimated glomerular filtration rate were not significantly different between the groups (p=0.823 and p=0.722, respectively). Renal units in the oxybutynin group had a greater likelihood of hydronephrosis improvement (61.9% vs 34.8%, p=0.011) and resolution of vesicoureteral reflux (62.5% vs 25%, p=0.023). Febrile urinary tract infection (29.2% vs 40%, p=0.404), completion of toilet training (70.8% vs 76%, p=0.748) and age at toilet training (p=0.247) did not differ significantly between the oxybutynin and observation groups. CONCLUSIONS: Oxybutynin enhances hydronephrosis improvement and vesicoureteral reflux resolution following primary endoscopic valve ablation in infants but periodic monitoring is warranted.

Urodynamic findings during the filling phase in neurogenic bladder patients with or without vesicoureteral reflux who have undergone sacral neuromodulation.

AIMS: To assess the urodynamic findings during the filling phase in neurogenic bladder patients with or without vesicoureteral reflux (VUR) who underwent sacral neuromodulation (SNM). METHODS: We retrospectively reviewed the records of 19 patients with neurogenic lower urinary tract dysfunction (NLUTD) who underwent SNM at our center from July 2018 to July 2019. Clinical data and video-urodynamic parameters were collected. VUR grading systems were used to evaluate upper urinary tract function. RESULTS: The mean test duration was 24 ± 8.2 days. The urodynamic evaluation showed a significant increase in the mean maximum cystometric capacity (136.3 ± 118.2 vs 216.5 ± 137.8 mL; P = .0071) and compliance (8.7 ± 8.52 vs18.3 + 16.47 mL/H2 O; P = .016), as well as a decrease in maximum intravesical pressure (57 ± 39.23 vs 36.58 ± 31.16 H2 O; P = .0064). In the voiding phase, none of the patients had automatic urination at the baseline and testing phases. In 8 of 19 patients who had detrusor overactivity (DO), the DO disappeared (four patients) or was delayed (four patients). The VUR in 3 of 12 ureter units disappeared. The grade of VUR or the volume before VUR improved in 8 ureter units, and the remaining 1 did not change significantly. An implant was performed in 16 cases. After permanent implantation, all patients needed intermittent catheterization to empty the bladder. CONCLUSIONS: This retrospective study indicates that SNM can improve the urinary storage function of the bladder in appropriate patients with NLUTD. For patients with VUR, SNM can cure or reduce VUR by improving DO and bladder compliance.

In utero myelomeningocele repair: The natural history of patients with incontinent pattern (sphincteric deficiency: leakage below 40 CMH20).

INTRODUCTION: Since 2011 we have been following prospectively myelomeningocele patients treated in utero with particular interest to patients with sphincter weakness/deficiency. We investigated the changes of bladder pattern and upper urinary tract with time in children who underwent in utero repair and had low-pressure incontinence based on urodynamic evaluation (UE). MATERIALS AND METHODS: From the 120 patients in our database, 117 had at least one UE. Of these, 30 were classified as incontinent when leaking at low pressure (<40 cmH20). We reviewed clinical evaluation, urinary tract ultrasound, voiding cystourethrography (VCUG), and other UE parameters at first and last evaluation. RESULTS: We found 30 cases (25.64%). Mean age at initial evaluation was 4.97 months followed by UE done initially at mean age of 5.73 months. Follow-up was 28.4 months. Febrile urinary tract infection has been found in four patients (13.3%), hydronephrosis in four patients, and bladder neck thickening in three (10%). The VCUG showed vesicoureteral reflux in three cases (3/27, 11.1%). A total of 90% of patients had detrusor overactivity with mean maximum detrusor pressure (33.37 cmH20). Only 16.67% of patients showed normal bladder capacity. From the 30 patients, 23 had at least two UE. We noticed a change of bladder pattern as follows: six patients became of high-risk pattern, five normal, and two with underactive bladder pattern. The average interval between the first and last UE was 25.5 months (median: 15 months). CONCLUSION: We concluded that 43.47% of patients with low DLPP have kept the incontinent pattern. If the initial LPP was below 30 cmH20, 70% remained with the incontinet pattern.

Accuracy of subjective vesicoureteral reflux timing assessment: supporting new voiding cystourethrogram guidelines.

BACKGROUND: Bladder volume at the onset of vesicoureteral reflux (VUR) is an important prognostic indicator of spontaneous resolution and the risk of pyelonephritis. OBJECTIVE: We aim to determine whether pediatric urologists and pediatric radiologists can accurately estimate the timing of reflux by examining voiding cystourethrogram (VCUG) images without prior knowledge of the instilled contrast volume. MATERIALS AND METHODS: Total bladder volume and the volume at the time of reflux were collected from VCUG reports to determine the volume at the onset of VUR. Thirty-nine patients were sorted into three groups: early-/mid-filling reflux, late-filling and voiding only. Thirty-nine images were shown to three pediatric urologists and two pediatric radiologists in a blinded fashion and they were then asked to estimate VUR timing based on the above categories. A weighted kappa statistic was calculated to assess rater agreement with the gold standard volume-based report of VUR timing. RESULTS: The mean patient age at VCUG was 3.1±2.9 months, the median VUR was grade 3, and 20 patients were female. Overall agreement among all five raters was moderate (k=0.43, 95% confidence interval [CI] 0.36-0.50). Individual agreement between rater and gold standard was slight to moderate with kappa values ranging from 0.13 to 0.43. CONCLUSION: Pediatric radiologists and urologists are unable to accurately and reliably characterize VUR timing on fluoroscopic VCUG. These findings support the recently published American Academy of Pediatrics protocol recommending the routine recording of bladder volume at the onset of VUR as a standard component of all VCUGs to assist in a more accurate assessment of the likelihood of resolution and risk of recurrent urinary tract infections.

Noncoding rare variants of TBX6 in congenital anomalies of the kidney and urinary tract.

Congenital anomalies of the kidney and urinary tract (CAKUT) are a wide range of congenital structural renal defects. CAKUT is the leading cause of chronic renal failure and end-stage renal disease in children. Studies in humans and animal models have confirmed the large genetic contribution to CAKUT. The previous evidence suggested that human TBX6 coding mutations might cause CAKUT via gene-dosage insufficiency. However, the potential involvement of TBX6 noncoding mutations in CAKUT remains to be elucidated. Here, we described DNA sequencing and copy-number analysis of TBX6 in 269 Chinese subjects with CAKUT. Interestingly, we identified two heterozygous noncoding variants of TBX6 in sporadic subjects with CAKUT: one is c.769-7delT, from a subject with duplex renal and collecting system, and the other is a 3' untranslated region (3'-UTR) variant (c.1392C>T) from a subject with unilateral renal hypoplasia. These two TBX6 noncoding variants are novel and extremely rare, respectively, in human populations archived in the ExAC database. The mini-gene splicing assay showed that the TBX6 c.769-7delT variant significantly reduced the splicing efficiency of TBX6 intron 5 when compared to the wild-type control. In this work, we identified a novel splicing variant of TBX6 in human CAKUT. Our experimental observations suggested that the TBX6 noncoding variant can affect gene expression and may potentially be involved in human CAKUT.

Ureteral Complications of Pediatric Renal Transplantation.

PURPOSE: Ureteral complications following renal transplantation are more common in children than in adults. We identify potential risk factors for ureteral complications in pediatric patients. MATERIALS AND METHODS: We retrospectively studied a cohort of patients who underwent renal transplantation at Lurie Children's Hospital between 2004 and 2016. We analyzed the associations between patient characteristics, operative factors, graft characteristics and postoperative complications. RESULTS: A total of 224 renal transplantations in 219 patients were identified. Preexisting bladder pathology was present in 25% of cases. Overall rate of ureteral complications was 16%, with symptomatic vesicoureteral reflux being the most common. Ureteral complications were seen significantly more frequently in patients with underlying bladder pathology (26% vs 12%, p = 0.01). Rate of postoperative vesicoureteral reflux in patients with bladder pathology was lower when a urologist performed the reimplantation but the difference was not statistically significant (15% vs 27%, p = 0.35). Urologists were significantly more likely to perform the ureteral anastomosis in patients on clean intermittent catheterization (85% vs 43%, p = 0.004) and in patients with a history of complex bladder reconstruction (75% vs 28%, p <0.001). CONCLUSIONS: Patients with existing bladder pathology are at increased risk for ureteral complications, particularly vesicoureteral reflux. Since pediatric urologists routinely perform ureteral reimplantation in patients with existing bladder pathology, these patients may benefit from a multidisciplinary approach between urology and transplant surgery at renal transplantation.

In utero myelomeningocoele repair and urological outcomes: the first 100 cases of a prospective analysis. Is there an improvement in bladder function?

OBJECTIVES: To evaluate the first 100 cases of in utero myelomeningocoele (MMC) repair and urological outcomes in a prospective analysis aiming to define possible improvement in bladder function. PATIENTS AND METHODS: We used a protocol consisting of a detailed medical history, urinary tract ultrasonography, voiding cystourethrography, and urodynamic evaluation. Patients were categorised into four groups: normal, high risk (overactive bladder with a detrusor leak-point pressure >40 cm H2 O and high filling pressures also >40 cm H2 O), incontinent, and underactivity (underactive bladder with post-void residual urine), and patients were treated accordingly. RESULTS: We evaluated 100 patients, at a mean age of 5.8 months (median 4 months), classified as high risk in 52.6%, incontinent in 27.4%, with underactive bladder in 4.2%, and only 14.7% had a normal bladder profile. Clean intermittent catheterisation was initiated in 57.3% of the patients and anticholinergics in 52.6%. Antibiotic prophylaxis was initiated in 19.1% of the patients presenting with vesico-ureteric reflux. CONCLUSION: The high incidence of abnormal bladder patterns suggests little benefit of in utero MMC surgery concerning the urinary tract.

Necessity of performing voiding cystourethrography for children with unilateral multicystic dysplastic kidney.

BACKGROUND: The purpose of this study was to resolve the clinical question as to whether all patients with unilateral multicystic dysplastic kidney (MCDK) should receive voiding cystourethrography (VCUG). METHODS: This is a retrospective study using cross-sectional analysis. Seventy-five children with unilateral MCDK were enrolled, excluding patients with other genetic or chromosome abnormalities, spinal cord diseases, or anal atresia. We reviewed their records from medical charts and calculated risk factors for abnormal VCUG using multivariate logistic regression analysis. RESULTS: Abnormal VCUG findings were present in 24 of 75 patients (32.0%), specifically, vesicoureteral reflux (VUR) in 8 (10.6%), including high-grade VUR in 2 (2.7%), and only lower urinary tract or bladder disease in 16 (21.3%). In multivariate analysis, only abnormal findings by ultrasonography was an independent risk factor for abnormal VCUG findings with statistical significance in multivariate analysis (OR 6.57; 95% CI 1.99-26.26; P = 0.002). When we excluded five patients who showed similar findings by ultrasonography and VCUG, abnormal findings by ultrasonography were again calculated as an independent risk factor (OR 4.44; 95% CI 1.26-28.42; P = 0.02). Sensitivity, specificity, positive predictive value, and negative predictive value of abnormal findings by ultrasonography to predict urologic anomalies by VCUG in these children were 83%, 59%, 49%, and 88%, respectively. Two children required a third ultrasonography to detect abnormal findings. CONCLUSIONS: We can select, using only abnormal findings by ultrasonography, children with unilateral MCDK who should undergo VCUG. We would also like to emphasize that ultrasonography should be performed repeatedly to detect congenital anomalies of the urinary tract.

Can we predict vesicoureteral reflux resolution in patients with non-neurogenic lower urinary tract dysfunction?

OBJECTIVE: To analyze factors influencing reflux resolution in patients with the coexistence of non-neurogenic lower urinary tract dysfunction and vesicoureteral reflux. METHODS: The data of 153 children who were diagnosed with vesicoureteral reflux and accompanying non-neurogenic lower urinary tract dysfunction between 2010 and 2015 were retrospectively evaluated. Patients with neurogenic and anatomical malformations, monosymptomatic nocturnal enuresis, previous history of vesicoureteral reflux surgery, irregular and/or incomplete follow-up data were excluded. After exclusion of 55 patients, 98 patients were enrolled in this study. Patients were divided into two groups according to the presence of spontaneous vesicoureteral reflux resolution during the follow-up period. Group 1 consisted of 54 children with spontaneous vesicoureteral reflux resolution, whereas group 2 included 44 children without resolution. Medical history, physical examination, urinalysis, uroflowmetry combined with electromyography, ultrasonography, as well as the Dysfunctional Voiding and Incontinence Symptom Score questionnaire were also evaluated. RESULTS: The mean age at presentation was 7.57 ± 0.23 years (range 5-13 years), and the mean follow-up period was 28.3 months. Significant differences were noted between the two groups in terms of dysfunctional voiding and incontinence symptom score, bladder wall thickness, and the post-void residual urine volumes. In addition, lower urinary tract symptoms, namely frequency, urgency and daytime incontinence, were found to be higher in group 2. In multivariate analysis, post-void residual urine volume and Dysfunctional Voiding and Incontinence Symptom Score were found to affect reflux resolution rates (P = 0.002, P = 0.002, respectively). CONCLUSIONS: The absence of significant post-void residual urine volume, and a low Dysfunctional Voiding and Incontinence Symptom Score increase the likelihood of spontaneous resolution rates of vesicoureteral reflux in children with non-neurogenic lower urinary tract dysfunction.

New trends in voiding cystourethrography and vesicoureteral reflux: Who, when and how?

Vesicoureteral reflux, retrograde flow of urine from the bladder into the upper urinary tract, is one of the most common urological diagnoses in the pediatric population. Diagnosis and subsequent management of urinary reflux have become increasingly debated in the past decade, with divergent opinions over which patients should be evaluated for reflux, and when detected, which children should receive intervention. Although some argue that vesicoureteral reflux is a "phenotype" that often resolves without intervention, others contest that untreated reflux has the potential to cause irreversible renal damage over time. Voiding cystourethrogram images the urethra and bladder during both bladder filling and emptying, as well as the ureters and kidneys when reflux is present, and is considered the gold standard for diagnosing vesicoureteral reflux. Once detected, therapeutic options for urinary reflux are diverse, ranging from observation with or without low-dose antibiotic prophylaxis to a variety of operative interventions. Management should be based on a multitude of factors including patient age, risk of subsequent urinary tract infections, risk of renal parenchymal injury, a given child's projected clinical course and parental preference. Over the past two decades, investigators have elucidated many crucial voiding cystourethrogram findings in addition to grade that provide significant prognostic information and are useful in determining the best course of action for a child on a more individualized basis.

Pelvic floor electromyography and urine flow patterns in children with vesicoureteral reflux and lower urinary tract symptoms.

OBJECTIVE: To determine the different urine flow patterns and active pelvic floor electromyography (EMG) during voiding in children with vesicoureteral reflux (VUR) as well as presenting the prevalence of lower urinary tract symptoms in these patients. MATERIALS AND METHODS: We retrospectively reviewed the charts of children diagnosed with VUR after toilet training from Sep 2013 to Jan 2016. 225 anatomically and neurologically normal children were included. The reflux was diagnosed with voiding cystourethrography. The study was comprised an interview by means of a symptom questionnaire, a voiding diary, uroflowmetry with EMG and kidney and bladder ultrasounds. Urine flow patterns were classified as bell shape, staccato, interrupted, tower and plateau based on the current International Children's Continence Society guidelines. RESULTS: Of 225 children with VUR (175 girls, 50 boys), underwent uroflowmetry + EMG, 151 (67.1%) had an abnormal urine flow pattern. An active pelvic floor EMG during voiding was confirmed in 113 (50.2%) children. The flow patterns were staccato in 76 (33.7 %), interrupted in 41 (18.2%), Plateau in 26 (11.5%), tower in 12 (5.3%) and a bell shape or normal pattern in 70 (31.5%). Urinary tract infection, enuresis and constipation respectively, were more frequent symptoms in these patients. CONCLUSIONS: Bladder/bowel dysfunction is common in patients with VUR that increases the risk of breakthrough urinary tract infections in children receiving antibiotic prophylaxis and reduces the success rate for endoscopic injection therapy. Therefore investigation of voiding dysfunction with primary assessment tools can be used prior to treating VUR.

Efficacy of onabotulinum toxin A injection in pediatric patients with non-neurogenic detrusor overactivity.

AIMS: To evaluate the effectiveness and reliability of onabotulinum toxin A (onaBoNT-A) injections in pediatric patients with non-neurogenic detrusor overactivity (NNDO). METHODS: Between January 2010 and February 2016, 39 patients underwent onaBoNT-A injections for NNDO, and were evaluated retrospectively. Three-day voiding diary was filled at baseline, and at the postoperative 9th month. The voiding frequency, incontinence episodes, and the cystometric capacity were noted. Vesicoureteral reflux (VUR) associated with NNDO, and presence of nocturia were recorded. Additional injection requirements were also stated. RESULTS: We reached the data of 33 patients on 9th month. The mean age was determined as 8.75 ± 3.01 (5-16) years. Initially, the mean bladder capacity was calculated as 114.66 ± 35.23 mL on the voiding diary, and 153.15 ± 47.40 mL on the baseline urodynamic study. After the procedures, the mean bladder capacity increased to 140.84 ± 45.61 mL (P = 0.0011), the mean daily voiding frequency decreased from 10.36 ± 1.05 to 7.42 ± 0.83 (P = 0.01), and the mean incontinence episodes decreased from 2.72 ± 1.87 to 1.18 ± 1.13 (P = 0.001), on voiding diary. VUR associated with NNDO was determined in 10 (30.3%) patients. The degree of VUR decreased three in patients, and VUR disappeared in five patients following the injections (P = 0.011). Fourteen (42.4%) patients had nocturia, and after the injections, nocturia disappeared in five (15.15%) patients (P = 0.151). Additional injections were required in 10 (30.3%) patients at the 9th month. CONCLUSIONS: OnaBoNT-A injections can be used in the pediatric patients with NNDO as an effective and reliable procedure by decreasing voiding frequency, incontinence episodes, and increasing bladder capacity, with negligible side effects and complications.

Vesicoureteral reflux and the extracellular matrix connection.

Primary vesicoureteral reflux (VUR) is a common pediatric condition due to a developmental defect in the ureterovesical junction. The prevalence of VUR among individuals with connective tissue disorders, as well as the importance of the ureter and bladder wall musculature for the anti-reflux mechanism, suggest that defects in the extracellular matrix (ECM) within the ureterovesical junction may result in VUR. This review will discuss the function of the smooth muscle and its supporting ECM microenvironment with respect to VUR, and explore the association of VUR with mutations in ECM-related genes.

[Reflux nephropathy in children: early diagnosis and monitoring].

Vesicoureteral reflux (VUR) is the most common type of obstructive uropathy in children. Reflux nephropathy (RN) is one of the most common complications of VUR that inevitably leads to chronic kidney disease. Patients with end-stage kidney disease require costly treatment, and the only way to cure them is kidney transplantation. A timely institution of renoprotective therapy is a key factor helping to preserve the function of the native kidneys. Hence, it is necessary to devise new highly sensitive and minimally invasive methods for early diagnosis of RN. The purpose of this article is to review the molecular mechanisms of initiation and progression of kidney fibrosis and the opportunities of instrumental and non-instrumental methods for its diagnosis. Special attention is paid to highly specific and highly sensitive non-invasive methods for the detection of minimal changes in the renal parenchyma. The authors discuss the promising biomarkers for the diagnosis and prediction of RN.

Assessment of kidney function in children by enzymatic determination of 2- or 24-h creatinine clearance: comparison with inulin clearance.

BACKGROUND: Although renal inulin clearance (Cin) is the gold standard for evaluation of kidney function, it cannot be measured easily. Therefore, creatinine clearance (Ccr) is often used clinically to evaluate kidney function. Enzymatically measured Ccr was recently found to be much higher than Cin because of the tubular secretion of creatinine (Cr). This study compared three measures of renal clearance, inulin, 2-h Ccr, and 24-h Ccr, in children. METHODS: Kidney function was evaluated in 76 children (51 males and 25 females) aged 1 month to 18 years with chronic kidney disease (CKD) by three renal clearance methods at almost the same time. RESULTS: Correlations between each pair of three renal clearance measurements were determined. Approximate glomerular filtration rate (GFR) was equal to 62 % of 2-h Ccr or 76 % of 24-h Ccr. CONCLUSION: Cr secretion by renal tubules was approximately 50 % of the GFR. In this study, we indicate that the measurements of 2-h Ccr or 24-h Ccr do not show true GFR but we could infer approximate GFR from the values. The use of 2- or 24-h Ccr might contribute to the treatment of pediatric CKD patients.

Prediction of High-grade Vesicoureteral Reflux in Children Younger Than 2 Years Using Renal Sonography: A Preliminary Study.

OBJECTIVES: To investigate the predictive value of renal sonography for vesicoureteral reflux (VUR) and the efficacy of renal sonography, technetium Tc 99m-labeled dimercaptosuccinic acid (DMSA) scanning, and a combination of the two for VUR screening in children younger than 2 years with a first episode of febrile urinary tract infection. METHODS: Thirty-eight patients younger than 2 years with a first febrile urinary tract infection were included in our study, which was conducted from April through October 2014. Each kidney was considered a separate renal unit. A retrospective review of clinical information and images (renal sonography, DMSA scanning, and voiding cystourethrography) was performed. RESULTS: Of the 14 renal units (18.4%) with VUR, 4 (28.5%) had high-grade VUR. Among single findings, dilatation of the renal collecting system, wall thickening of the renal collecting system, and DMSA scans significantly predicted VUR (P= .038, .027, and .01, respectively). Dilatation was the most common single finding (46 of 76 renal units). The sensitivity values for dilatation, wall thickening, and DMSA scans were 85.7%, 64.2%, and 50.0%, and the negative predictive values were 93.3%, 89.7%, and 87.9%. CONCLUSIONS: The negative predictive values indicate that normal renal sonographic and DMSA findings can predict the absence of high-grade VUR. We propose that renal sonographic findings of wall thickening as well as dilatation of the renal collecting system should be considered predictive of high-grade VUR.

Urological evaluation of patients that had undergone in utero myelomeningocele closure: A prospective assessment at first presentation and early follow-up. Do their bladder benefit from it?

AIMS: To report our data on initial urological presentation after in utero myelomeningocele (MMC) closure. METHODS: A prospective urological assessment at first presentation was designed for patients that had undergone in utero MMC closure and referred to our urological facility. The protocol consisted of detailed medical history, renal sonography, voiding cystourethrogram, and urodynamic evaluation. RESULTS: In utero MMC closure was performed in 19 patients at gestational age of 25.6 weeks 25-27. Birth occurred at a mean gestational age of 31.8 weeks 26-36. Hyperactive bladder was observed in 89.5% 17/19. Bladder compliance was normal in two cases (10.5%), was markedly reduced in 10 patients (52.6%) and not possible to be determined due to urinary leakage in 7 patients (36.8%). We observed normal bladder capacity in 8 patients (42.1%), reduced in 11 (57.9%), and detrusor-sphincter dyssynergia in 9 patients (47.4%). Underactive bladder was diagnosed in one case. Clean Intermittent Catheterization was initiated by 11 patients (57.9%) mostly in association with anticholinergics 10/11. Vesicoureteral reflux was found in 5 patients (26.3%) and 9 had pyelonephritis at a mean follow-up of 5.4 months 2-17. CONCLUSIONS: Our data suggested that despite in utero MMC surgery, patients are at risk for bladder abnormal function and renal deterioration and should be aggressively treated, not differently from those operated in the post-natal term. This study has the merit of being a prospectively set evaluation performed by one investigator, including the urodynamic study. We acknowledge the need of long-term follow up.