Study of 99 m-Tc DMSA (Dimercaptosuccinicacid) Scintigraphy in children with urinary tract infection

Abstract

Introduction: DMSA scan is superior to ultrasonography in detecting cortical scars, although the later identifies dilatation of the collecting systems and renal swelling. This study was conducted to know the role of 99m- Tc Dimercaptosuccinic acids (DMSA) scan in children with UTI, its role in the early detection of renal scar. Materials and Methods: A study was conducted among 125 children at Dr. B.R. Ambedkar Medical College, Bangalore from August 2015- October 2017. The study group included both inpatient and outpatient children with urinary tract infection. The patients with culture positive urinary tract infections during first and recurrent attacks were studied and followed from 3 months to 2 years. On follow- up 99m -Tc DMSA scan was conducted, if needed USG abdomen and MCU scan were conducted. Results: 44% of the children showed abnormal features both by DMSA scan and USGand 21.6% of the children had normal scan but found to have abnormality in DMSA scan. On follow- up of the children, it was noticed that in 56% of the DMSA scan was normal, in 6% of children who initially had renal scar, on follow up did not have renal scar. 24% of the children persisted to have renal scar on follow up and 12% who initially had normal DMSA scan, on follow up had scar. In that 12 children with renal scar, all the children had VUR grade 4-5. Conclusion: 99m-Tc DMSA scintigraphy is the gold standard for early identification and evaluation of acute renal inflammation and subsequent renal scarring. This study recommends both renal ultrasound scanning and 99m-Tc DMSA scintigraphy to be routinely performed in infants and children with a first febrile UTI because ultrasonography alone as low sensitivity for the detection of renal cortical abnormalities.