It is documented that vesicoureteric reflux (VUR) is a predisposing factor for UTI, which in turn may involve the kidney parenchyma and cause permanent renal scarring.
Although the exact prevalence in the general population is unknown, 30-40% of children with urinary tract infections (UTI) are found to have reflux. Furthermore, UTIs occur approximately in 5-10% of children. This prospective study from Sri Lanka was done on 808 children below the age of 12 years with the initial episode of UTI in the time period between 1992 to 2004.
Voiding cystourethrogram (VCUG) was performed in all children less than two years with a confirmed UTI and in children who had abnormalities on ultrasound or DMSA scan. There was 101/333 (30%) VCUGs showing VUR. VUR was graded according to the International Classification. Children with primary VUR who had completed more than six years of follow up were included for the present analysis. There were fifty-six children who fulfilled the criteria. All of them were treated with low-dose antibiotic prophylaxis until the age of five years. After discontinuation of prophylaxis they were followed up periodically with assessment of the clinical status, blood pressure and proteinuria.
Children with primary VUR who had completed more than six years of follow up were included for the present analysis. There were fifty-six children who fulfilled the criteria. These 56 children with primary VUR were followed up for a period of 6-12 years (mean 8 years); 62.5% were boys with a male to female ratio of 1.7:1. Mean age at presentation was 1.95 years (range 1 month -12 years). Seventy six percent were below the age of two years. Thirty-three patients (58.9%) had unilateral reflux with 20 on the right side and 13 on the left; in 23 (41.1%) it was bilateral. The majority (48.2%) had grade III reflux while 28.6% had grade II and 8.9% had grade I reflux. High grade reflux was seen less frequently with grade IV in 12.5% and grade V in 1.8% of patients, respectively. Thirty-one (55.3%) had detectable renal scars on DMSA scan. Seventy five percent of children with VUR grades IV-V and 49% children with grade I-III had detectable renal scars on DMSA scan but, the difference was not statistically significant (P = 0.2). The study had a 15.3% breakthrough UTI rate during antibiotic prophylaxis, but they did include bilateral higher grades of VUR (grades IV-V) that may explain the higher percentage of breakthrough infections with the numbers already in the literature.