Open ureteric reimplantation by cross trigonal technique described by Cohen is considered a common surgical option for correction of vesicoureteral reflux (VUR). There is a lack of evidence in literature though for what happens to such kidneys, in the long run, particularly those which are poorly functioning.

To assess the long-term outcomes of ureteric reimplantation in poorly functioning kidneys in children with unilateral primary VUR.

Children with unilateral primary VUR and a relative renal function of less than 35% who underwent open or laparoscopic ureteric reimplantation between January 2005 and January 2017 were included in the study. Patients who had a follow up of less than five years were excluded. Preoperative evaluation consisted of a voiding cystourethrogram and Dimercaptosuccinic acid (DMSA) scan. In the follow-up period, patients underwent a diuretic scan at 6 weeks and 6 months. Follow up ultrasound was done for change in grade of hydronephrosis and retrovesical ureteric diameter. Subsequent follow up was done at 6 monthly intervals with evaluation for proteinuria and hypertension and any recurrent urinary tract infection (UTI). For assessment of cortical function, DMSA was repeated annually for 5 years after surgery. A paired-samples t-test was used to test the mean difference of DMSA between pre-post observations.

During this period, 36 children underwent ureteric reimplantation for unilateral primary VUR. After excluding those with insufficient follow-up, 31 were included in the analysis. Most of the patients were males (n = 26/31, 83.8%). Patient's age (mean ± SD, range) was 5.21 ± 3.71, 1-18 years. The grades of VUR were grade II (1 patient), grade III (8 patients), grade IV (10 patients), and grade V (12 patients). The pre and postoperative DMSA was 24.064 ± 12.02 and 24.06 ± 10.93, which was almost the same (statistically equal, paired-samples t-test: P = 0.873). The median (range) follow-up duration was 82 (60-120) mo. One patient had persistent reflux after surgery (preoperative: grade IV, postoperative: grade III), and the very same patient developed recurrent UTI. The difference in the preoperative and postoperative DRF was less than 10% in 29 patients. In one patient, the DRF decreased by 17% (22% to 05%) while in another patient, the DRF increased by 12% (25% to 37%) after surgery. None of the patients had an increase in scarring after surgery. 15% of patients were hypertensive before surgery and all of them continued to be hypertensive after surgery while none developed hypertension after surgery. None of the patients had significant proteinuria (> 150 mg/d) during the follow-up period.

Children with unilateral primary VUR and poorly functioning kidney maintain the renal function over the long term in most cases. Hypertension and proteinuria do not progress over time in these patients.

Perusal of recent guidelines relating to proper evaluation of infants and children with urinary tract infection (UTI) suggests that the occurrence of vesicoureteral reflux (VUR) may not have the clinical import previously ascribed to this anatomic abnormality. Patients with a solitary kidney uniquely allow investigation of the effects of both vesicoureteral reflux (VUR) and urinary tract infection (UTI) on renal growth unencumbered with the inevitable questions of laterality that confound analysis in patients with two kidneys. Several previous studies with conflicting results have addressed whether vesicoureteral reflux (VUR) impacts ultimate renal size in children with a solitary kidney. Few published studies have considered the occurrence of both urinary tract infection (UTI) and VUR on the degree of compensatory hypertrophy. This is the largest series to date investigating the effect of both UTI and VUR on the degree of compensatory hypertrophy with time.

Our objective was to analyze sonographically determined renal growth in patients with a solitary kidney, stratifying for both the occurrence and severity of UTIs and the occurrence and severity of VUR.

We retrospectively reviewed the clinical history (including bladder and bowel dysfunction (BBD)) and radiology reports of 145 patients identified as having either a congenital or acquired solitary kidney in our pediatric urology practice from the prior 10 years. UTIs were tabulated by severity, where possible, and the grade of VUR was recorded based on the initial cystogram. Sonographically determined renal length was tabulated for all ultrasounds obtained throughout the study. Based on a mixed-effects model, we investigated the influence of UTI and VUR on renal growth.

Of the 145 patients analyzed, 105 had no VUR and 39 had VUR (16 = Gr I&II, 11 = GIII, 12 = GIV&V). Comparison showed that there was no difference in the occurrence of UTI between those without VUR (27/105 with UTI) and those with VUR (15/39 with UTI; p = 0.14). There was no difference in the occurrence of BBD in patients with VUR (15/39) and those without VUR (36/106, p = 0.62). While neither VUR nor UTI alone affected renal growth in the solitary kidney, the three-way interaction term among age, VUR, and UTI was significant (p = 0.016). The growth of the kidneys in the various patient groups is depicted in the table. From the analysis, a refluxing solitary kidney with UTI showed a significantly lower growth rate than the other groups (p < 0.001).

This study is limited by the inherent selection bias of retrospective studies. Additionally, the variability of sonographic renal measurement is well recognized. Lastly, our sample size did not allow us to incorporate the severity of the UTIs and the grades of VUR in our final regression model. Nevertheless, the overall patterns suggest that when both VUR and UTI are present, the solitary kidney demonstrates less renal growth with time. Study of larger cohorts of patients with solitary kidneys will be necessary to confirm our observations and discern what, if any, are the consequences of high-grade VUR and upper tract UTI in these patients.

In the largest series to date we were able to discern no independent effect of either VUR or UTI on sonographically determined renal growth in patients with a solitary kidney. However, UTI and VUR together result in kidneys that are smaller than other solitary kidneys not so affected. Follow-up studies of larger cohorts seem warranted to confirm these findings and discern the clinical import of these smaller kidneys.

We retrospectively reviewed the results of ureteral reimplantation in infants with primary vesicoureteral reflux (VUR) to evaluate the effect on prevention of urinary tract infection (UTI) and renal growth.

From July 1991 to December 2001, a total of 205 infants (180 boys and 25 girls) with primary VUR underwent ureteral reimplantation at the Department of Urology, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan. Indications for surgery were high-grade reflux (grade IV-V), breakthrough UTI and non-compliance of medical treatment. Age at surgery raged from 1 to 11 months (mean, 6.4 months). Ureteral reimplantation was performed according to Cohen's method. Only two of 336 refluxing ureters required ureteral tailoring. Follow-up ranged from 12 to 110 months (mean, 64 months). Surgical outcome, frequency of UTI and individual renal growth measured by (99m)Tc-dimercaptosuccinic acid (DMSA) scintigraphy was evaluated.

Postoperative ultrasound and voiding cystourethrography showed neither residual reflux nor ureterovesical obstruction. Contralateral low grade reflux occurred in six of 74 patients (8.1%) who had unilateral reflux preoperatively. After reimplantation, 10 patients documented 13 febrile UTI. Eleven of the 13 episodes occurred early in the postoperative period (<6 months). Frequency of febrile UTI reduced from 0.23538 before surgery to 0.00894 and 0.00081 per patient per month at 6 and 12 months after surgery, respectively. No development of renal scarring was seen in postoperative DMSA scan. Changes of differential renal function was <0.05 in all patients.

The present results show ureteral reimplantation in infants is safe and very effective for the prevention of UTI. After surgical treatment in infancy, individual renal growth of children with primary VUR is stable.

To evaluate the renal growth pattern in patients with primary vesico-ureteric reflux (VUR) using long-term measurements of split renal function with 99mTc-dimercaptosuccinic acid (DMSA) scintigraphy.

In all, 712 children aged < 16 years (466 boys and 246 girls) with primary VUR were referred to our hospital from July 1991 to December 2000. VUR was diagnosed by voiding cysto-urethrography. The patients were treated either surgically (group 1) or conservatively (group 2) and followed with serial 99mTc-DMSA scintigraphy for up to 10 years. There were 942 examinations in 367 of 712 patients who had repeat scintigraphy. Patients with secondary VUR, VUR to a solitary or fused kidney, or upper urinary tract obstruction, were excluded. Five of 298 patients (1.7%) who had ureteric reimplantation had a febrile urinary tract infection (UTI) soon after surgery but none recurred (recurrence is an indication for surgery in children with VUR); there was no febrile UTI in the 69 patients in group 2. Planar scintigraphy with 99mTc-DMSA was used to assess the absolute uptake (AU) of each kidney, measured as a percentage of the injected dose, and the relative uptake (RU = AU of each kidney/AU of both kidneys) calculated. The initial examination was at least 4 weeks after any febrile UTI in most patients. Serial studies were conducted 1 year after surgery and then biannually in group 1. In group 2 the DMSA scan was repeated every 2-3 years. The change in split renal function was compared with the RU of the right kidney.

The RU of the right kidney at the initial scan correlated closely with those on repeated scans in both groups. The correlation coefficients were 0.99 in group 1 and 0.94-0.97 in group 2 at every study. The change of RU remained within 0.05 in all patients after treatment.

Under strict control of UTI, split renal function in children with primary VUR does not change. There may be no possibility of accelerated or compensatory growth of the kidney with reflux nephropathy, but no concern about deterioration and atrophy either.

We sought to apply 2-dimensional sonographic measurements of renal parenchymal area in children with high grade vesicoureteral reflux to assess reliability and accuracy in estimating differential renal function, and in predicting clinical outcome compared to traditional 1-dimensional sonographic measurements.

We retrospectively evaluated 121 sonograms from 30 patients with a grade 4 or 5 primary vesicoureteral reflux, including 14 who underwent ureteral reimplantation during followup and 16 who were followed on prophylactic antibiotic therapy. One-dimensional sonographic measurements of longitudinal length and bipolar thickness were determined in refluxing and contralateral kidneys, as were 2-dimensional measurements of longitudinal parenchymal area using computer planimetry. Renal length, bipolar thickness and parenchymal area were compared to renal function data determined by nuclear renography. Renal length and area was also represented as a percent of age adjusted normal values using previously published nomograms.

Differential renal function correlated well with differential parenchymal area for all patients (r = 0.924). This correlation persisted in patients with (r = 0.917) and without scarring (r = 0.890), as determined by dimercapto-succinic acid scan. Differential length did not correlate as well (r = 0.661) and bipolar parenchymal thickness did not correlate at all (r = 0.021). Sonographic age adjusted area of the refluxing kidneys was approximately two-third normal. No statistically significant difference was observed among age adjusted renal area of the observation, preoperative and postoperative groups. Contralateral kidney area was not significantly different than normal.

Our data indicate that serial sonographic measurements of longitudinal renal parenchymal area provide a simple and accurate method of monitoring renal growth and function in patients with high grade vesicoureteral reflux. In contrast to 1-dimensional measurements of renal length and bipolar parenchymal thickness, renal parenchymal area correlates well with renal function. Area also appears to be a more sensitive method of monitoring renal growth in children with vesicoureteral reflux.

Physical growth was studied in 6 males and 16 females during 1 year of antimicrobial prophylaxis and during the 2 years following subsequent surgical treatment for severe primary vesicoureteric reflux. Surgery was performed between the ages of 2 and 8 because of either repeated breakthrough infection or persistence of grade III or IV reflux. Height and weight velocities were calculated as yearly rates and then converted into interquartile ratios (IQRs). Neither the mean centile height nor weight attained varied significantly between that at entry, after 1 year of medical treatment and at 2 years after surgery. However, the mean IQR for height velocity (+/- sem) rose significantly from -0.61 (+/- 0.45) during antimicrobial prophylaxis to 0.54 (+/- 0.25) following surgery. Similarly, the mean IQR for weight velocity rose significantly from -0.63 (+/- 0.50) during medical treatment to 0.47 (+/- 0.24) following surgery. These results suggest that surgical treatment is preferable to continued medical treatment in patients with severe primary vesicoureteric reflux who fail to respond to a trial of antimicrobial prophylaxis.

This study presents the result of 12-21 years' follow-up in a group of children with neonatal urinary tract infection (onset within 1 month after birth) in whom early renal growth retardation was noted without concomitant classical renal scarring. In all cases the neonatal infection was diagnosed and treated within a few days of onset and the patients were closely supervised thereafter. Renal length, parenchymal thickness and area were measured at urography. At first follow-up (22 children, mean age 4.1 years) a significant reduction of renal parenchymal thickness was noted. Long-term follow-up (18 patients, mean age 17 years) demonstrated a normalization of renal size in the entire group, although less complete in the subgroup with reflux. There were two major findings in the present study. Firstly, renal growth retardation was seen after neonatal infection, both with and without reflux. Secondly, normalization of renal size in previously small kidneys was demonstrated, suggesting that growth retardation can be a reversible phenomenon. The tendency for such normalization was slightly more marked in children without reflux. Reduction of parenchymal thickness without calyceal deformity, therefore, does not necessarily mean irreversible damage, and differentiation between permanent scarring and temporary growth retardation can thus only be made at later follow-up, possibly not until after puberty. The demonstration of renal growth retardation in spite of early diagnosis and treatment emphasizes the great vulnerability of the kidney in the newborn.

To assess the effectiveness of the surgical correction of vesico-ureteric reflux, current renal function was determined in 56 children with scarred kidneys who had undergone ureteric reimplantation between 1978 and 1983. The children were aged between 2 and 15 years, had no coexisting urological disease and a glomerular filtration rate (GFR) of less than 90 ml/min/1.73 m2. In the 32 patients who had bilateral reimplantation of ureters draining bilaterally scarred kidneys the improvement in GFR following surgery was highly significant (P less than 0.001), with improvement occurring in 75%. The greatest improvement was in patients where the GFR was less than 50 ml/min/1.73 m2 (29%). Individual kidney GFR was estimated in 42 kidneys and 81% improved after surgery. This improvement was highly significant (P less than 0.001).

Renal growth was studied for periods ranging from 2 to 22 years (average 9·4) in 70 children who presented between 2 weeks and 12 years of age with urinary tract infection and who were found to have vesicoureteric reflux. They were managed on a conservative regimen of continuous prophylaxis and regular, complete voiding. Renal growth over the entire period of observation was normal in relation to the child's growth in height in 100 of the 111 kidneys originally drained by refluxing ureters. During the time that reflux was known to be still present, renal growth was within normal limits in 101 kidneys. Renal growth was impaired in 11 kidneys. Ten of them were exposed to a recurrence of urinary tract infection. The eleventh child had an unproved symptomatic infection. Seven of these kidneys were also already scarred and 4 had gross reflux. In 2 of these children a fresh scar developed, one in a previously normal kidney. Because of the tendency for reflux to disappear, the renal growth during the first 2 years of observation was also analysed. A significant association was found between impaired growth and, independently, infection and renal scarring. No independent association was found between impaired growth and the severity of reflux. Small kidneys tended to grow at the expected rate. If growth was compared in pairs of kidneys with unilateral reflux, no difference in rate could be found if the kidneys were unscarred, but a significant difference was found if the refluxing ureter drained a scarred kidney; this tended to grow slowly, and the unscarred non-refluxing kidney tended to accelerate in growth. The small group of kidneys which grew least well had established severe scarring associated with severe persisting vesicoureteric reflux and each had a further infection during the period of observation, although no rise in plasma creatinine concentration was observed in any of these children. It is in such children that the results of a controlled comparison of medical and surgical management will be of greatest value.