Renal Doppler ultrasound resistive index vs. renal scintigraphy with 99mTc-DTPA as diagnostic test for ureteropelvic junction obstruction in children

Objective: A cross-sectional study was carried out with the objective of evaluating the usefulness of Doppler ultrasound with resistive index (RI) measure compared with renal scintigraphy with Tc-99m-DTPA in children with unilateral ureteropelvic junction obstruction. Methods: The study included children under 15 years with a diagnosis of unilateral ureteropelvic junction obstruction, healthy contralateral kidney with or without an antecedent of ureteropyeloplasty. The selected patients were sent to the Nuclear Medicine Department to carry out a renal scintigraphy with Tc-99m-DTPA and days later were sent to the Radiology Department for the performance of Renal Doppler Ultrasound with RI. Results: A total of 21 patients were included in the study, 15 males and 6 females, representing 71.4% and 28.6%, respectively. Mean age was 5.3 years. Only 3 had an antecedent of ureteropyeloplasty in the affected kidney. The scintigraphy reported data of unilateral obstruction in 18 patients, including the 3 patients with previous surgery. The average glomerular filtration rate (GFR) obtained with the scintigraphy was 100.28 ml/min. The average GFR in affected kidneys was 43.03 ml/min and 57.24 ml/min in healthy kidneys (p < .001). Doppler ultrasound with RI reported ectasia in 100% of the affected kidneys and one normal contralateral kidney. The average RI in affected kidneys was 0.69 mm/s and 0.50 mm/s in healthy kidneys (p < .001). Conclusions: With the results obtained, we can suggest that ultrasound Doppler with measurement of RI can be an alternative toot to renal scintigraphy with Tc-99m-DTPA in some cases. (C) 2019 AEU. Published by Elsevier Espana, S.L.U. All rights reserved.