TECHNETIUM-99M-DMSA STUDIES IN PEDIATRIC URINARY-TRACT INFECTION

Urinary tract infection (UTI) is a common condition in children and ma y lead to renal scarring with a risk of later hypertension and renal i nsufficiency, We made a cross-sectional study of the Tc-99m-DMSA findi ngs in 496 children referred for following symptomatic UTI to a Depart ment of Nuclear Medicine and we categorized the results, to provide a framework for further study. Method: A standard Tc-99m-DMSA protocol w as used to study 496 children (157 males, 339 females) aged from birth to 14 yr, Findings were classified according to the image appearance and relative function of each kidney, These were related to age, sex, history and timing of UTI and the results on micturating cysto-urethro graphy (MCU), Results: Images were normal, with function within normal limits (45%-50% in one kidney), in approximately half the boys and gi rls studied. The other images were classified as equivocal in 68 child ren, abnormal unilaterally in 105 and bilaterally in 76, and they were subdivided according to the image appearance, No image changes could be identified that were specifically associated with acute UTI. Diffus e change alone was uncommon. A high proportion of abnormal images was found in infant boys, older girls with recurrent UTI and those childre n with vesico-ureteric reflux (VUR), Of the bilateral abnormal images, 98% were seen in children with VUR, Conclusion: Our findings suggest that infective renal change may be superimposed on underlying congenit al lesions (perhaps detectable antenatally) or may be acquired followi ng UTI in the presence of reflux and are thus potentially preventable, This study also suggests that VUR is almost certain to have occurred in a child who has bilateral abnormal (TC)-T-99m-DMSA images following UTI and is also commonly present in those with definite unilateral de fects.