F + 0 diuresis renography in infants and children

Full text: The purpose of the study was to evaluate the results of modifying diuretic renography in the investigation of hydronephrosis and hydroureteronephrosis by the simultaneous administration of 99Tcm-MAG3 and frusemide. Two parameters were assessed: (1) the diuretic response in normal kidneys and (2) the ability to differentiate renal obstruction from non-obstruction. A prospective study was performed in infants and children in whom venous access was deemed to be difficult. Seventy-two patients were involved in the 3-year study. There were 48 males and 24 females with ages ranging from 2 days to 7 years (median age of 6 weeks). Following the intravenous administration of 99Tcm-MAG3 and frusemide simultaneously, 20-min dynamic studies of the kidneys and bladder were obtained. Post-gravity-assisted drainage images were also obtained. The patients were then followed up for 6-12 months and the results of the F+0 study were compared to the final diagnoses, based on either surgical findings or conservative management with repeat ultrasound and 99Tcm-MAG3 studies. There were 151 renal units in 72 patients with 55 normal non-obstructed renal units and 96 abnormal renal units. All 55 normal renal units showed excellent diuretic responses with clearance half-times of 1.3-6.3 min (mean 3.8 min). Fifty-three abnormal renal units were classified as non-obstructed and 43 renal units as obstructed. Of the 53 non-obstructed renal units, there were 48 true-negatives and five false-negatives; of the 43 obstructed renal units, there were 40 true-positives and 3 false-positives. The sensitivity was 88.9%, specificity 94.1 % and accuracy 91.7%. In conclusion, F+0 diuresis renography shows an excellent diuretic response in normal kidneys and is a valid method for the investigation of hydronephrosis or hydroureteronephrosis in infants and children