Posterior Urethral Valve: Factors Affecting the Renal Outcome

Background: Posterior urethral valve (PUV) is the most common cause of lower urinary tract obstruction in male children with associated sequlae. Different factors, such as age at presentation, initial and nadir serum creatinine, renal parenchymal echogenicity on initial USG, vesicoureteric reflux (VUR) , recurrent UTI, bladder dysfunction and the presence or absence of pop-off mechanism like VURD have significant impact on ultimate renal outcome. The main aim of the study was to observe the effects of different prognostic factors like age of presentation and preoperative VUR of the PUV respondents on postoperative long term renal outcome as well as changes of renal function status on the basis of initial and postoperative serum creatinine level in our settings. Material & Methods: This was a quasi-experimental study and conducted in the Department of Pediatric urology of Bangladesh Shishu Hospital and Institute, Dhaka. We enrolled 58 male children of different ages having posterior urethral valve, who were admitted in the pediatric urology department from July,2018 to Dec,2021. Results: Total 58 patients included in our study. Among all patients 53.4% were aged between 1 month to 1 year, 39.7% of them were more than 1 year old and 6.9% of them were neonates. Among 31 respondents, 32.3 % had poor renal function & 35.5 % of them also had moderately impaired renal function. Again, out of 23 respondents, 30.4% had poor renal function & 6% had moderately impaired renal function. The relation between age category and postoperative renal function status (On the basis of postoperative eGFR) of the posterior urethral valve respondents were statistically not significant. Patients who had no VUR, 66.7% of them had normal renal function, 25% had moderately impaired renal function and 8.3% had poor renal function. Respondents who had bilateral VUR, 55% of them had poor renal function and 35% had moderately impaired renal function. Among respondents who had unilateral VUR, 28.6% of them had poor renal function and 28.6% had moderately impaired renal function but 42.9% had normal renal function. The relation between preoperative VCUG findings and postoperative long term renal function status of the PUV patients were statistically significant. 7 (100%) respondents who had preoperative abnormal renal function, more than 71.4% of them had returned to normal renal function after operative procedure. But abnormal renal function was present in 2 (28.6%) patients during follow up. In our study we found 29.3% of our patients had poor renal outcome and 29.3% patients had moderately impaired renal function within the mean follow up period of 19.33±12.38 months (ranges from 9months to 4 years). Conclusion: Our research highlights the significance of age at presentation, despite its statistically negligible effect on long-term renal outcomes. However, among the children with PUV following valve ablation and with a long-term follow-up, beginning serum creatinine and the presence of various types of VUR on initial VCUG had a significant effect (p.05) on postoperative renal function on the basis of serum creatinine.

Cranberry in children: prevention of recurrent urinary tract infections and review of the literature

Urinary tract infections (UTI) are common in childhood. In 30-50 percent of children with UTI the infections occur recurrently, especially in those with vesicoureteral reflux (VUR), neurogenic bladder (NB), previous cystitis or pyelonephritis and malformative uropathies. To reduce the likelihood of UTI, antibiotic prophylaxis has been regarded as the therapeutic standard for many years. However, the disadvantage of long-term antibiotic therapy is the potential for development of collateral effects and resistant organisms in the host. Such reasons have induced scientists to search for alternative modalities of UTI prevention and have contributed to determining the increasing desire for "naturalness" of the population and preventing excessive medication. The use of cranberry fulfils these needs by potentially replacing or enhancing traditional procedures. The purpose of this study was to assess the effectiveness of cranberry in preventing UTI in pediatric populations. We searched Pubmed, the Cochrane Central Register of Controlled Trials and Internet. Cranberry in patients with previous UTI was evaluated in three studies, cranberry in patients with VUR in three studies and four studies analyzed the efficacy of cranberry in children with NB. In seven of nine studies cranberry had a significant effect in preventing UTI.

Urinary Protein and Enzyme Excretion of Spot Urine in Children with Vesicoureteral Reflux

PURPOSE: The aim of this study was to evaluate the clinical usefulness of measurement of beta2 microglobulin (beta2 MG), N-acetyl-beta-D-glucosaminidase (NAG) of spot urine samples as indices of renal tubular damage and microalbumin of spot urine samples as a parameter of glomerular damage in children with vesicoureteral reflux (VUR) or renal defects. METHODS: We studied 91 children with previous UTI. The children were classified as 62 children without VUR and renal defects (group I), 10 children with VUR, without renal defects (group II), and 19 children with VUR and renal defects (group III). Patients having VUR were separated according to the degree of VUR (mild VUR: VUR grade I-III, severe VUR: VUR grade IV-V). Urinary excretion of beta2 microglobulin (beta2 MG), microalbumin, N-acetyl-beta-D-glucosaminidase (NAG), creatinine were measured in samples of morning urine specimens. Children with VUR or renal defects detected by voiding cystourethrography (VCUG) and DMSA renal scan were investigated. RESULTS: Microalbumin/Cr ratio of spot urine was significantly increased in group III compared group I (42.3+/-27.2 mg/gCr vs 25.2+/-10.9 mg/gCr, P<0.05). NAG/Cr ratio of spot urine was significantly increased in group II compared group I (3.70+/-23.4 mg/gCr vs 18.7+/-12.7 mg/gCr, P<0.05). There was no statistically significant difference of beta2 MG/Cr ratio among three groups. CONCLUSION: Urinary microalbumin excretion of morning urine sample may be a simple and reliable clinical indicators for early identification of renal damage in children with VUR and renal defects. Urinary microalbumin excretion may be useful marker to predict the the severity of VUR.

Vesicoureteral Reflux and Urinary Tract Infection in Children with Congenital Hydronephrosis

PURPOSE: We checked voiding cystourethrography (VCUG) in patients with congenital hydronephrosis (CHN) and followed up the occurrence of urinary tract infection(UTI) in these patients. And we tried to figure out the relationship between CHN and VUR and UTI. METHODS: We performed a retrospective study in 122 CHN patients who received VCUG from 2002 to 2008 at Ajou University Hospital. We executed logistic regression, chi-square test and T-test using version 16.0 SPSS package for the statistical analysis. P<0.05 was regarded as significant. RESULTS: Most patients with CHN were male (73%) and there was a tendency of preferences for unilateral (77%) and left (84%) occurrence of hydronephrosis. The incidence of VUR was 18.9 % among 122 CHN patients and no laterality difference was found to the severity of VUR or hydronephrosis. The incidences of VUR and UTI was higher in group of higher grade (III-IV) CHN patients, when compared to the lower group, respectively. When VUR was present in CHN patients, the incidence of UTI during infancy was also higher. CONCLUSION: The incidence of VUR was higher in patients with higher grades of CHN. The incidence of UTI during infancy was higher when VUR was present in the CHN patients.

The Clinical Characteristics of Infantile Primary Vesicoureteral Reflux and Its Spontaneous Resolution Rate

PURPOSE: Childhood primary VUR is generally diagnosed after urinary tract infection, is more prevalent among girls and has a low spontaneous resolution rate in cases of severe VUR. The aim of the present study is to examine the age and gender-related characteristics and the spontaneous resolution rate of infantile primary VUR. METHODS: The medical records of 96 infants with primary VUR, diagnosed after their first UTI, were retrospectively reviewed(1995-2004). The clinical characteristics including gender, the degree of VUR and presence of renal scars were evaluated. The spontaneous resolution rate and contributing factors were also analyzed. RESULTS: Infantile primary VUR was more prevalent in males than females. The percentage of atrophic scarred kidney was significantly higher in males than females(17.2% vs 3.4%)(P<0.05). The cumulative spontaneous resolution rate in 3 years was very high(89.1%), and was not significantly different between gender and among VUR grades. But in the first year, the spontaneous resolution rate of severe refluxing ureters was significantly higher in males than in females(46.2% vs 7.1%)(P<0.05) and the spontaneous resolution rate of refluxing ureters with no scarred kidneys was significantly higher than those associated with atrophic scarred kidneys(76.6% vs 20%)(P<0.05). CONCLUSION: Infantile primary VUR was more prevalent among males and tends to be associated with atrophic scarred kidneys in male infants. The cumulative spontaneous resolution rate in 3 years was very high, even in high-grade VUR and associated atrophic scarred kidneys. In infantile primary VUR, surgery should be withheld even in infants with high-grade VUR with atrophic scarred kidneys.

Necessity of (99m)Tc-dimercaptosuccinic acid scan in infants with low grade vesicoureteral feflux / 소아과

OBJECTIVE: (99m)Tc-dimercaptosuccinic acid(DMSA) scan is considered to be the most sensitive examination for detection of renal scars. However, because of its high radiation exposure to the kidney and its limited usefulness for patients with low grade vesicoureteral reflux(VUR), some authors have suggested that DMSA scans should be reserved primarily for children with VUR grade 3 and above. The aim of this study was to reevaluate the necessity of DMSA scans as a screening test in infants without reflux or with low grade reflux. METHODS: In this retrospective study, 189 infants(mean age:6.2 months) diagnosed as UTI were enrolled. Voiding cystourethrogram(VCUG), DMSA scan and renal ultrasonography were performed within 1 month of UTI. VUR grade was classified into three subgroups; low grade(grade 1-2), moderate grade(grade 3), and high grade(grade 4-5), respectively. RESULTS: Renal defects were present in 67 of 189 infants, and 82 of the 378 renal units. The incidence of renal defects was significantly correlated with VUR grade(P<0.01); 28 percent without reflux, 38 percent with low grade, 53 percent with moderate grade, 100 percent with high grade, respectively. However, there was no significant differences in incidence of renal defects between the low grade and moderate grade group. CONCLUSION: In this study, renal defects were found in quite high percentages; 28 percent patients without reflux and 38 percent patients with low grade VUR, respectively. Moreover, there was no significant difference in the incidence of renal defects between the low grade and moderate grade groups. Therefore, DMSA scan should be performed for infants with UTI as a screening test regardless of the presence of VUR.

Results of Surgical Correction in Patients with Vesicoureteral Reflux after Kidney Transplantation / 대한이식학회지

PURPOSE: The prevalence and significance of vesicoureteral reflux (VUR) after kidney transplantation has been varies among authors. While these results suggested that VUR can be a source of repeated infections, which might be a prognostic factor impairing long-term graft function. We evaluated the prevalence, clinical manifestations and diagnostic methods of VUR after living donor kidney transplantation and their proper management with the results of each treatment. METHODS: We reviewed thirty-four patients among five hundreds and thirteen living donor kidney transplant recipients, who developed VUR after the transplantations at our center from June 1998 to June 2003. Twenty-three patients underwent a corrective surgical procedure, ureteroneocystostomy, and we excluded 3 patients who underwent the procedure less than 1 year. The patients were divided into three groups: those with severe VUR underwent a corrective surgical procedure with more than 1 year follow-up (group I, n=20), those with mild VUR underwent a conservative management (group II, n=8) and control group of patients without VUR (group III, n=20). The incidence of urinary tract infection (UTI) and graft function were assessed for 1~7 years. Voiding cystoureterography (VCUG) was performed in patients with recurrent urinary tract infections and reflux was classified from Grade I to Grade IV. RESULTS: We examined immunological and non-immunological risk factors such as age, sex, primary diseases, duration on dialysis, diuresis prior to the treatment, donor selection, the degree of HLA mismatches, cold ischemia time, the incidence of acute rejection. There was no significant demographic difference among study groups except sex (female). Analysis of patients and grafts survival rates revealed no statistical differences among three groups. CONCLUSION: VUR dose not seem to negatively affect graft function if surgical correction were performed in proper period after the diagnosis. The indication of surgical correction of VUR is clinically significant UTIs, UTI sepsis, Grade III or IV VUR. Close attention, proper diagnosis and prompt surgical correction are necessary to minimize the adverse influence of VUR after kidney transplantation.

Value of the Voiding Cystourethrography Prior to Renal Transplantation / 대한비뇨기과학회지

PURPOSE: A retrospective review of the medical records of 168 patients who were evaluated for renal transplantation was undertaken to determine whether a voiding cystourethrography (VCUG) influenced the surgi cal care of the recipient. MATERIALS AND METHODS: Between June 1989 to May 1998, 168 patients received a transplantation at our center. These patients proceeded to transplantation, with all of them receiving a VCUG as part of their evaluation. We compared incidence of postoperative complications between normal VCUG group and abnormal group during follow up period (mean 31. 6 months). RESULTS: An urologic abnormality was identified by VCUG in 15 (8.9%) of 168 patients and all of them were vesicoureteral reflux (VUR). In 15 patients with VUR, grade of VUR were grade I in 2, grade II in 10, grade III in 2 and grade IV in 1. None of them with VUR required surgical intervention and had postoperative complications related to VUR. CONCLUSIONS: The VCUG is not essential for the preparation of potential recipients for renal transplantation and should be utilized selectively in individuals with a history of urologic disease or when urinary tract abnormalities are identified by physical examination or an abnormal urine analysis.

Factors Associated with Renal Scar in Children with Vesicoureteral Reflux

PURPOSE : The urinary tract infection associated with vesicoureteral reflux(VUR) in children may result in serious complications such as renal scarring, hypertension, proteinuria and end stage renal disease. The purpose of this study was to evaluate the factors affecting renal scar such as age, gender, grade of VUR, and ACE gene polymorphism, and body growth in the patients with and those without renal scar associated with VUR METHODS : During the period from January 1994 to July 2000, We had 93 children with urinary tract infection associated with VUR who were admitted to the Department of pediatrics of Chonbuk National University Hospital. The patients were divided into two groups according to follow up 99mTc-DMSA renal scan; patients with renal scar group and those with non-scar group. We analyzed and compared the factors associated with renal scarring between the two groups. RESULTS : There were no significant difference in gender, causative organism, ACE gene polymorphism, height and weight at diagnosis between renal scar group and non-scar group. Fifty four patients were in renal scar group and forty seven of them had VUR. The age at diagnosis was significantly higher in renal scar group (2.48 +/-2.64yr) than in non renal scar group (1.26+/-1.83yr). Especially, the infants who were less than 1 year of age with VUR developed relatively more renal scar compared with infants older than 1 year of age. The incidence of renal scarring showed a direct correlation with the severity of VUR. CONCLUSION : The factors affecting renal scar formation were age at diagnosis, presence and grade of VUR, but the other factors such as gender, causative organism, ACE gene polymorphism were not associated with renal scarring. Therefore, further evaluation about uropathogenic E. coli and follow up study about body growth associated with severity of renal scar would be necessary.

Changes in the Findings of 99mTc-dimercaptosuccinic Acid(DMSA) Scan after Acute Pyelonephritis in Childhood and Renal Scar

PURPOSE: We evaluated the change in the findings of DMSA scan after acute pyelonephritis (APN), and the relationship between renal scar formation and risk factors such as vesicoureteral reflux (VUR), organism and inflammatory reaction. METHODS: We examined 200 patients under the age of 5 years with first APN. DMSA scan, voiding cystourethrography (VCUG), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were performed initially. If the initial DMSA scan was abnormal, it was repeated after 6 months. RESULTS: Median age was 1.1 years. Initial renal defects existed in 136 (68%) of 200 cases. At 6 months after initial infection, follow up DMSA scan was checked in 61 children with initial renal defects for evaluation of scar. Initial renal defects disappeared in 19 (31%)children. Initial renal defects were present in 60 (64%) of 94 kidneys with the VUR, however, they were present in 94 (31.0%) of 306 kidneys without VUR(P0.05). CRP was 11.0+/-7.0mg/dL in 127 patients with initial renal defects and 4.4 5.5mg/dL in 53 patients without initial renal defects (P<0.05) and CRP was 13.0+/-4.7mg/dL in 39 patients with scar and 8.7+/-4.6 mg/dL in 19 patients without scar in follow up DMSA scan (P<0.05). CONCLUSION: The presence of VUR and higher CRP level are risk factors for initial renal defects but renal scarring occured higher in the higher level of CRP, irrespective of VUR.

Two Cases of Congenital Urethral Stenosis with Recurrent Urinary Tract Infection / 대한비뇨기과학회지

Congenital urethral stricture are uncommon in boys and occurs at the junction of the endodermal primary urethra and ectodermal secondary urethra. This structure is thought to be related embryonically to failure of complete dissolution of urogenital membrane at the junction of the urogenital sinus and genital fold. Endoscopically, this lesion is recognized as a ring-form stenosis just distal to the external urethral sphincter. Congenital urethral stricture is an important cause of recurrent urinary tract infections, enuresis, failure in thrive or hematuria in pediatric urological practice. The most effective treatment of this lesion is optic internal urethrotomy under direct vision. We report two cases of 6 and 12-year-old boys hospitalized with complaints of high fever, dysuria, urgency and frequency. Six-year-old boy has grade III VUR and 12-year-old boy has grade IV VUR with Hutch diverticulum. We managed with visual internal urethrotomy only in 6-year-old boy but visual internal urethrotomy and bilateral ureteroneocystostomy in 12-year-old boy.

Treatment of primary vesicoureteral reflux in children / 대한비뇨기과학회지

We performed a retrospective review to evaluate the result of the management on primary vesicoureteral reflux in 36 children (59 refluxing ureters) during a 11-year period (1980 to 1990). Based upon the international classification, the vesicoureteral reflux was grade 1 in 6 cases (11.1 %). grade II in 14 (23.7 %), grade II in 13 (22.1 %), grade IV in 15 (25.4%) and grade V in 11 (18.6%) and designed to compare the risk or benefit of medical and surgical treatment as initial management for this. The group or primary medical management included with total 42 ureters and as the results of the management the reflux was completely disappeared in average 8.2 months at 22 ureters and 13 ureters were secondarily operated because of progressed reflux to recurrent urinary tract infection despite of appropriate medical treatment. The group of primary surgical management included with 3 ureters of grade III, 7 in grade IV, 7 of grade V, total 17 ureters and then 1 ureter of which was re-operated due to progressed reflux, but all reflux were cured. And we checked the 99m technetium-dimercapto-succinic acid renal scan to detect renal scars at pre-treatment in 33 ureters (22 patients) and post-treatment in 21 ureters (14 patients). As the results, the renal scars were detected in 17 ureters at pre-treatment patients. And during follow up, there were no changes of the renal scar at post-treatment in 18 ureters, but a new scar was developed in 3 ureters (grade II in I, grade IV in 2) even though having medical treatment. The radionuclide renal scan was highly sensitive to detect the scar, so should be performed.

Evaluation of Renal Scarring in Children with Primary Vesicoureteral Reflux by 99m Tc-DMSA Renoscintigraphy / 대한비뇨기과학회지

To assess the presence and the severity of renal scarring in primary vesicoureteral reflux (VUR), 11 children (3 girls and 8 boys, 19 kidneys) underwent intravenous pyelography (IVP) and 99m Tc-dimercaptosuccinic acid (DMSA) renoscintigraphy and the following results were obtained : 1. Of 19 kidneys, renal margin was shown in 5(26.3% ) and renal scar was revealed only in 3 (15.8%) on IVP. 2. Renal margin in all ( 100.0% ) and renal scar in 12 (63.1%) of the kidney were revealed on 99m Tc-DMSA renoscintigraphy. 3. On the follow-up ranging from 6 months to 13 years after surgical reconstruction, 8 kidneys showed no reversible improvements in renal scar except one, in which progression of renal scar was noted. We concluded that 99m Tc-DMSA renoscintigraphy is more valuable than IVP in evaluating the degree of renal scar and the renal margin.