Clinical course of 735 children and adolescents with primary vesicoureteral reflux.

The purpose of this retrospective cohort study was to report the clinical course of children with primary vesicoureteral reflux (VUR). Between 1970 and 2004, 735 patients were diagnosed with VUR and were systematically followed in a single tertiary renal unit. Patients were followed up for a mean time of 76 months (6 months to 411 months). The events of interest were reflux resolution, renal damage, urinary tract infection (UTI), chronic kidney disease (CKD), and hypertension. Survival analysis was performed in order to evaluate reflux resolution and CKD. Renal damage was detected at admission in 319 patients (43.4%). Continuous low-dose antibiotic prophylaxis was administered to 624 patients (91.2%); 499 (73%) patients subsequently had no UTI or fewer than three episodes. The median time of persistence of reflux according to Kaplan-Meier analysis was 38 months for grade I/II [95% confidence interval (95% CI), 33-43], 98 months for grade III (95% CI, 78.5-105), and 156 months for grade IV/V (95% CI, 122-189). Twenty patients (3%) developed hypertension. It was estimated that the probability of CKD was 5% at 10 years after diagnosis of VUR; for children diagnosed after 1990 the probability of CKD was only 2%. Renal function impairment occurred in patients with severe bilateral reflux or in patients with contralateral renal hypoplasia. There has been an improvement of prognosis for patients diagnosed in the past 15 years.

Gender and vesico-ureteral reflux: a multivariate analysis.

The aim of this retrospective cohort study was to describe the characteristics of patients with primary vesico-ureteral reflux (VUR) with special attention to gender-specific differences. Between 1970 and 2004, 735 patients were diagnosed with VUR and were systematically followed in a single tertiary renal unit. The following variables were analyzed: race, age at diagnosis, clinical presentation, weight and height Z-score, unilateral/bilateral reflux, VUR grade, renal damage, severity of renal damage, constipation, and dysfunctional voiding. Comparison of proportion between genders was assessed by the chi-square test with Yates' correction. The logistic regression model was applied to identify independent variables associated with gender. A survival analysis was performed to evaluate VUR resolution. After adjustment, five variables remained independently associated with male gender at baseline: non-white race [Odds ratio (OR) = 1.98, 95% confidence interval (95% CI) 1.33-2.95, P=0.001], moderate/severe grade of reflux (OR=2.16, 95% CI 1.45-3.22, P<0.001), severe renal damage (OR=1.60, 95% CI 1.04-2.52, P=0.04), age at diagnosis <24 months (OR=1.79, 95% CI 1.23-2.60, P=0.002), and antenatal clinical presentation (OR=3.56, 95% CI 1.91-6.63, P<0.001). Follow-up data were available for 684 patients (93%). Median follow-up time was 69 months (range 6 months to 411 months). Girls had a greater risk of urinary tract infection (UTI) during follow-up than boys (OR=1.68, 95% CI 1.18-2.38, P=0.003). There was no difference in progression to chronic renal insufficiency (CRI) between boys (3.8%) and girls (2.4%) during this period of follow-up (OR=1.58, 95% CI 0.59-4.15, P=0.44). Gender as an isolated variable is a poor predictor of clinical outcome in an unselected series of primary reflux. Although boys had a more severe pattern at baseline, girls had a greater risk of dysfunctional voiding and recurrent UTI during follow-up.

Features of primary vesicoureteral reflux and renal damage in children at a single institution in Brazil from 1969 to 1999.

OBJECTIVES: The purpose of the study was to evaluate the clinical/radiological features of patients with primary vesicoureteral reflux (VUR) admitted to a single institution from 1969 to 1999. METHODS: The patients' records were retrospectively reviewed and the following clinical data obtained at admission were analyzed: age, gender, race, date of entry, previous symptoms, weight, height, blood pressure, and serum renal function. The renal imaging tests at baseline were also retrospectively analyzed including voiding cystourethrography, excretory urography, DMSA scan, and ultrasonography. For statistical analysis, reflux was classified into two categories: (1) mild/moderate (grade I/II/III) and (2) severe (grade IV/IV). Renal damage was categorized according to the following classification: (I) mild, focal damage; (II) moderate, more extensive scars, and (III) severe, generalized damage or shrunken kidney. The odds ratio (OR) and the respective confidence interval (95%CI) were calculated to compare the difference in risk between groups. RESULTS: A total of 461 patients were enrolled in the protocol. There was a predominance of female gender (71%) and white race (73%). Mean age at VUR diagnosis was 2.8 y and 93% of the patients had urinary infection before admission. Bilateral reflux was diagnosed in 249 (54%) children, for a total of 710 renal units for study. The distribution of reflux grade was as follows: grade I (7%); II (36%); III (26%); IV (23%), and V (8%). Of the 450 children investigated, 180 (40%) presented with renal damage, for a total of 234 (26%) units with renal scars. Renal damage was associated with the following factors: Diagnosis after 2 y of age (OR = 1.5, 95%CI = 1.08-2.1, p = 0.01), severe degree of reflux (OR = 6, 95%CI = 4-9, p < 0.001). There was a significant risk of severe renal damage for male gender (OR = 1.9, IC95% = 1.3-2.1, p = 0.001). CONCLUSION: There was a predominance of renal damage in children diagnosed above 2 y and with a high degree of reflux. Severe renal damage was associated with male gender.