COMPARISON OF DIRECT RADIONUCLIDE CYSTOGRAPHY AND VOIDING CYSTOURETHROGRAPHY IN DIAGNOSIS OF MISSED VESICOURETERAL REFLUX IN CHILDREN WITH RECURRENT URINARY TRACT INFECTION

Urinary tract infections (UTI) are one of the most common infections in children. Vesico ureteral reflux (VUR) is a major risk factor for recurrent UTIs which can result in renal scarring. The diagnostic tests that are being used to detect VUR include voiding cystourethrography (VCUG) and direct radionuclide cystography (DRC). The sensitivity of each modality is controversial. In this study we attempt to identify the role of DRC in detecting possible VUR in patients without VUR in VCUG and Vice Versa. In this analytical study, we included 60 patients (120 kidney units) with recurrent urinary tract infection referred to nephrology clinic at Shahid Motahary Children Hospital. In the first step, 34 children (68 kidney units) without VUR in VCUG underwent DRC and 26 patients (52 kidney units) who had negative results for VUR in DRC underwent VCUG image. Eventually, all patients underwent DMSA imaging to detect renal scars and the results were analyzed using statistical tools. Study unit consists of 60 children with boys equaling to 13(21.7%) and girls 47 (84.3%) with average age of 4.7 years. DRC study applied for those with negative result of VCUG imaging in 68 kidney units detected 37 (54.5%) new unidentified VUR cases meanwhile; VCUG study just detected 7 (13.5%) neglected VUR with DRC study. According to the significant statistical difference between two modalities one can deduce that DRC has higher diagnostic value in detecting missed VUR. 70 unites out of the total of 120 kidney units had scars in kidney which equals to 58.5%, of which 43 unites (61.5%) were positive for VUR. The results implies a very significant relationship between having scar in DMSA studies and having VUR. It can be deduced that having repeated tests of DRC or VCUG can detect missed VUR in patients with recurrent urinary tract infections. Furthermore, DRC study is more valuable than VCUG and in the case of having significant scars on DMSA having repeated tests of cystography can boost detecting missed VUR.