PURPOSE: Children with lower urinary tract dysfunction and vesicoureteral reflux, at cystography assessment, frequently present alterations in the lower urinary tract anatomy such as dilated posterior urethra, irregularity of the bladder wall and diverticula. However, the significance of these findings is unknown. The objective of this study is to evaluate the incidence of these findings, their time of disappearance and their correlation with the severity of the reflux. MATERIALS AND METHODS: 193 children with vesicoureteral reflux, considered simple, in the age group above 5 years at the moment of diagnosis, were analyzed. The recommendation for follow-up of these patients was one voiding cystoureterography (VCUG) each year. Only patients with a minimum of 2 VCUGs performed in a period of at least 6 months were considered. The VCUGs were classified as positive and negative in relation to findings that were characteristic of lower urinary tract dysfunction (LUTD). RESULTS: From the 193 children analyzed, 50 (26%) presented positive VCUG and 143 negative VCUG. From the patients without symptoms of lower urinary tract dysfunction (n = 135), 12 (9%) presented positive VCUG and 123 (91%) a negative VCUG. From the patients with negative VCUG, 68 (48%) presented unilateral reflux and 75 (52%) presented bilateral reflux. From those with positive VCUG, 26 (52%) had unilateral reflux and 24 bilateral reflux (48%). This difference was not statistically significant. A higher incidence of grade II reflux was more evident in patients with negative VCUG and degree III in patients with positive VCUG (p < 0.05). CONCLUSIONS: Our study demonstrated that 64% of the patients with LUTD and reflux presented findings in the VCUG that suggest dysfunction.

PURPOSE: To assess the value of intravenous urography (IVU) in detecting and grading the renal scar, comparing its results with those of scintigraphy with dimercaptosuccinic acid (DMSA). MATERIALS AND METHODS: The study included 43 children investigated by DMSA and IVU, who had vesicoureteral reflux diagnosed and classified through voiding cystourethrography. RESULTS: Among the kidneys with reflux, there was agreement between the results of DMSA and IVU concerning the presence and the absence of scars in 82.4% of the cases. Based on the results obtained, IVU would have a sensitivity of 66.6%, specificity of 94.4%; accuracy of 82.5%; positive predictive value (PPV) of 90% and negative predictive value (NPV) of 79%, when compared with DMSA results. Our data also confirm the close relation between the reflux grade and the presence of renal scar, since 75% of the kidneys with grade IV and V reflux presented scars. In relation to the grading of nephropathy, in 78% of patients the classification of the scar by both methods was identical. The highest disagreement was verified in the group with segmental scar on DMSA, where 41.6% of the kidneys were classified as normal on IVU. CONCLUSION: The data obtained confirm that the scintigraphy with DMSA is essential in the investigation of patients with renal scar, and cannot be replaced by IVU, due to its low sensitivity and lower ability of satisfactory grading.