Acute unilateral obstruction of ureter. Disparity in divided renal function calculated from 131I-hippuran and 99mTc-DTPA renography.

Fifteen patients with acute unilateral obstruction of ureter and 30 control patients were studied with simultaneous 131I-Hippuran and 99mTc-DTPA gamma camera renography. In severe outflow obstruction the relative function of the obstructed kidney was higher when calculated with Hippuran than with DTPA. No difference was found in the control subjects. This means that the glomerular filtration rate of an obstructed kidney may be relatively more reduced than the renal blood flow. Therefore, measurement of the single kidney fraction of total glomerular filtration rate has to be calculated with a glomerular filtered tracer, e.g., 99mTc-DTPA.