Prediction of Kidney Damage in Ultrasound Compared with Dimercaptosuccinic Acid in Children with Pyelonephritis and Vesicoureteral Reflux

Abstract

Background and purpose: Ultrasound is easily available, cheap, non-invasive and radiation-free that could be considered as an alternative to Dimercaptosuccinic Acid (DMSA) in evaluation of kidney damage. The aim of this study was to determine the prediction of kidney damage in ultrasound compared with DMSA (standard method) in children with pyelonephritis and vesicoureteral reflux. Materials and methods: This cross-sectional study was performed in children aging one month to 18 years old with pyelonephritis and vesicoureteral reflux grade 2 and higher admitted in Amirkola Children's Hospital, 2011-2020. Renal ultrasound was done in all children at admission and DMSA was done after at least 4-6 months. Then, sensitivity, specificity, and positive and negative predictive values of ultrasound were studied. The kappa coefficient was determined for the percentage agreement between ultrasound and DMSA. Results: Out of 220 children with pyelonephritis and reflux, 153 were included in the study. In ultrasound, out of 306 kidneys, 262 (85.6%) and 44 (15.1%) were normal and abnormal, respectively, but DMSA showed 128 (41.8%) normal and 178 (58.2%) abnormal kidneys. The sensitivity and specificity of ultrasound in predicting kidney damage compared with DMSA were 19% (CI: 12-27%) and 86% (CI: 97-74%), respectively. The positive and negative predictive values of ultrasound compared with DMSA in predicting kidney damage were 82% (CI: 68-68%) and 24% (CI: 17-31%), respectively. Conclusion: Based on current study, ultrasound alone is not able to predict kidney damage following pyelonephritis and vesicoureteral reflux and DMSA should be performed. If the ultrasound is normal, the chances of detecting kidney damage are much lower in DMSA.

Keywords

• ultrasound
• kidney damage
• dimercaptosuccinic acid
• pyelonephritis
• vesicoureteral reflux