Reappraisal of the effectiveness of ⁹⁹mTc-dimercaptosuccinic acid scans for selective voiding cystourethrography in children with a first febrile urinary tract infection

Kaohsiung J Med Sci. 2014 Dec;30(12):608-12. doi: 10.1016/j.kjms.2014.10.005. Epub 2014 Nov 15.

Abstract

Recent studies have yielded conflicting results regarding the ability of technetium-99m dimercaptosuccinic acid ((99m)Tc-DMSA) renal scans for identifying high-grade vesicoureteral reflux (VUR) in children with a first febrile urinary tract infection (UTI). This study aimed to reevaluate the effectiveness of (99m)Tc-DMSA renal scans for selective voiding cystourethrography (VCUG) in children with a first febrile UTI. The medical records of children aged ≤ 5 years who were admitted with a first febrile UTI were retrospectively reviewed. Ultrasonography (US) and DMSA renal scans were performed within 3-5 days after admission, and VCUG was performed 7-10 days after antibiotics treatment. A total of 653 children were enrolled for analysis, including 579 patients aged < 2 years (Group A) and 74 patients aged 2-5 years (Group B). In Group A, DMSA scans were abnormal for 346 patients (59.8%), and normal for 233 patients (40.2%). High-grade VUR was present in 99 of 346 patients (28.9%) with abnormal DMSA scans, but present in only 16 of 233 patients (6.9%) with normal DMSA scans (p < 0.001). Regarding the prediction of high-grade VUR, the sensitivity and negative predictive value (NPV) for the DMSA scans were 86.1% and 93.1%, respectively. In Group B, DMSA scans were abnormal for 36 patients (48.6%), and normal for 38 patients (51.4%). High-grade VUR was present in 12 of 36 patients (33.3%) with abnormal DMSA scans, whereas none of the 38 patients with normal DMSA scans had high-grade VUR (p < 0.001). The sensitivity and NPV of the DMSA scans were both 100%. Using the selective VCUG strategy, approximately 40% of Group A patients and 50% of Group B patients could be spared an unnecessary VCUG, respectively. Our study results suggest that (99m)Tc-DMSA renal scans are effective in identifying children with a first febrile UTI for selective VCUG.

Keywords: (99m)Tc-DMSA renal scan; Ultrasonography; Urinary tract infection; Vesicoureteral reflux; Voiding cystourethrography.

MeSH terms

  • Child
  • Female
  • Fever / complications*
  • Fever / diagnostic imaging*
  • Humans
  • Male
  • Radionuclide Imaging
  • Technetium Tc 99m Dimercaptosuccinic Acid*
  • Urethra / diagnostic imaging
  • Urinary Bladder / diagnostic imaging
  • Urinary Tract Infections / complications*
  • Urinary Tract Infections / diagnostic imaging*
  • Urination*

Substances

  • Technetium Tc 99m Dimercaptosuccinic Acid