RESUMO
The aim of this study was to find an accurate, easily available and safe imaging modality as an alternative to intravenous urography for the diagnosis of acute urinary obstruction. This retrospective study included 332 patients, who underwent both excretory urography (EU) preceeded by plain radiograph as well as ultrasonography for evaluation of acute flank pain. There were 198 male and 134 female patients. The presence or absence of urinary stones, level of obstruction, excretion delay on EU and dilated excretory system on either or both techniques were recorded. The sensitivity, specificity, predictive values, and accuracy for plain radiograph, ultrasonography, and for both modalities together were measured considering EU as a standard reference. The sensitivity and specificity of combined plain radiograph and ultrasound were 97% and 67%, respectively, with positive and negative predictive values and accuracy rates of 92%, 99%, and 97%, respectively. Our study suggests that the combination of plain radiograph and ultrasonography yields a high sensitivity, negative predictive value, and accuracy in depiction of urinary stones. Thus, EU need not be used as a routine diagnostic procedure in patients with acute obstructive uropathy.
