Validation of the renogram with immediate diuretic stimulus

Abstract

Objective The aim of this study is to determine the diagnostic reliability of the renogram with diuretic stimulus simultaneously at the administration of the dose, comparing two groups of 59 patients each one (F0 and F+10), to select patients for surgery. Material and Methods This is a retrospective study including two groups of 59 patients in whom the diuretic renogram was carried out by stimulus (furosemide), due to suspicion of ureteropelvic or vesicoureteral obstruction, using 99m Tc-Mercaptoacetylglicine. In the first one, the study was conducted applying the diuretic stimulus 600 seconds after the administration of the dose of the radiotracer (F+10). In the second one, it was carried out simultaneously to the administration (F0). For the interpretation, visual analysis, the parameters of the curves and the percentage of elimination after modification by the severity and micturition were evaluated. Statistical analysis of the information was made. Results The F+10 renogram shows a sensitivity of 96.7 %, specificity of 96.1 %, positive predictive value of 90.6 %, and a negative predictive value of 98.6 %. The F0 renogram shows a sensitivity of 95.2 %, specificity of 98.9 %, positive predictive value of 95.2 %, and a negative predictive value of 98.9 %. Conclusion The performance of the renogram by means of the administration of diuretic stimulus at the same time as the administration of the radiotracer is a useful and comfortable method in paediatric patients, and does not mean a significant loss in the efficacy parameters of the test in the selection of patients for surgery.