NEW YORK (Reuters Health) – Tc-99m dimercaptosuccinic acid (DMSA) renal scanning is not an accurate test for identifying children with dilating vesicoureteral reflux (VUR), suggest results of a meta-analysis.

Acute-phase DMSA renal scanning can’t be recommended as a replacement for voiding cystourethrography (VCUG) in the evaluation of young children with a first febrile urinary tract infection (UTI), the study team concludes in the July issue of Pediatrics, available online now.

Dr. Matthew Falagas, from Alfa Institute of Biomedical Sciences, Athens, Greece and colleagues point out that the type and/or sequence of imaging studies needed during the first febrile UTI in young children is the subject of debate.

Some investigators have claimed that because acute-phase DMSA renal scan results are abnormal in the presence of dilating VUR, normal DMSA scan results makes VCUG unnecessary in the primary examination of infants with UTI.

To investigate further, Dr. Falagas and colleagues analyzed 13 relevant cohort studies. These studies involved children with a first-episode of culture-proven febrile UTI and provided data on the ability of DMSA renal cortical scintigraphy performed within 3 months of diagnosis to identify VCUG-confirmed dilating VUR.

Nine studies involved patients younger than 2 years old, three involved children aged 16 or younger, and one involved enrolled neonates only. The researchers conducted both patient-based and renal unit-based analyses.

Overall, the accuracy of DMSA renal scanning for identifying VUR (grades III-V) was “rather poor.”

The pooled sensitivity and specificity rates of DMSA scanning were only 79% and 53%, respectively, for the patient-based analysis, and only 60% and 65%, respectively, for the renal unit-based analysis, the researchers report.

The respective areas under the hierarchical summary receiver operating curves were 0.71 and 0.67. A value of 0.80 to 0.90 is generally considered indicative of a good diagnostic testing, they point out.

There are also limitations to the use of DMSA renal scanning in children with UTI; it’s more costly than the combined cost of VCUG and renal ultrasonography; it requires intravenous access, is time-consuming and requires special equipment and facilities.

The results of their meta-analysis, Dr. Falagas and colleagues say, corroborate recommendations from the American Academy of Pediatrics to perform ultrasonography and VCUG alone in infants 2 to 24 months with UTI.

Pediatrics 2011;128.