Follow-up of acute pyelonephritis in children by Tc-99m DMSA scintigraphy - Quantitative and qualitative assessment

Purpose: The author's goal was to create a system to identify children at r isk for development of progressive renal damage, Methods: Thirty-four children were examined with Tc-99m DMSA scintigraphy i n the acute stage of an initial episode of pyelonephritis, after 6 months, and again after 1 year, The scintigraphic findings were correlated with cli nical and laboratory data, Results: All children had parenchymal defects in the acute stage: 93% of th e kidneys and 85% bilaterally, After 6 months, the defects had diminished o r disappeared in 66% of the kidneys, New defects appeared in 22%, At 1 year , no further improvement was seen in the kidneys, with an improved or uncha nged pattern at 6 months, New defects appeared in 34%, Mean kidney activity uptake expressed as the percentage of administered dose (KU/AD), was low i n the acute stage, increased at 6 months, with no further significant incre ase at 1 year, Eighty-three percent of children with urine cultures growing greater than or equal to 10(4) bacteria/ml at follow-up had decreased KU/A D values, whereas all children with urine cultures growing < 10(4) bacteria /ml had increased KU/AD values. Conclusions: Quantitative assessment increases the sensitivity of Tc-99m DM SA scintigraphy. Follow-up with this method makes it possible to identify t he children with decreasing renal tubular function who may be at risk for p rogressive renal damage, Moderate bacteria of 104 bacteria/ml urine is asso ciated with deterioration of renal tubular function.