AGE-RELATED AND SEX-RELATED TC-99(M)-DMSA RENAL UPTAKE AT 24 H IN CHILDREN WITH A NORMAL SCINTIGRAM

We performed a retrospective study to determine the age-and sex-relate d normal values of absolute Tc-99(m)-DMSA uptake at 24 h in children w ith normal kidneys. Of the 576 scintigrams performed between 1993 and 1996, 136 (272 kidneys) were classified as `normal' by two independent observers on the basis of the presence of a smooth cortical outline, the absence of cortical loss, relative uptake in the range 45-55% and normal echographic parenchymal findings. The 136 scintigrams were divi ded into eight groups based on the children's age: Group I,,<1 month ( 2 boys); Group II, 1-3 months (6 boys, 8 girls); Group III, 4-7 months (7 boys, 6 girls); Group IV, 8-12 months (8 boys, 8 girls); Group V, 13-24 months (14 boys, 4 girls); Group VI, 25-36 months (6 boys, 13 gi rls); Group VII, 37-120 months (13 boys, 19 girls); Group VIII, 121-18 0 months (8 boys, 10 girls). In contrast to the results of Morris et a l. using absolute Tc-99(m)-DMSA uptake at 4-6 h, we found that combine d left and right kidney uptake increased until age 8 months (Group I, 22.0 +/- 6.7%; Group II, 45.9 +/- 5.0%; Group III, 50.8 +/- 5.0%; Grou p IV, 56.9 +/- 8.5%; P=0.019), after which it reached a plateau (Group V, 55.4 +/- 7.3%; Group VI, 60.1 +/- 7.8%; Group VII, 62.0 +/- 5.0%; Group VIII, 62.4 +/- 6.3%). Uptake at 24 h tended to be lower in the g irls than in the boys, but this difference was not significant.