A comparison between diuresis renography and the Whitaker test in 64 kidneys.

Fifty-seven patients have provided 64 dilated pelvicaliceal units for study by diuresis renography and the Whitaker test. Of 45 kidneys showing a type I or type IIIa renographic response (unobstructed), 32 were, according to Whitaker's criteria, obstructed, 8 fell into an equivocal zone and only 5 were unobstructed. Thirty-five of these kidneys--33 of which were associated with moderate or severe loin pain--were operated on for presumed obstruction with generally excellent symptomatic and renographic result. Thus the detection of a type I or type IIIa response in a dilated, painful system cannot be taken to exclude obstruction. Better correlation was obtained between renography and the Whitaker test in patients exhibiting a type IIIb or type II renographic response. Diuresis renography is a sensitive indicator of urodynamic disturbance in the upper urinary tract and an ideal means of evaluating post-operative progress. The Whitaker test provides a reliable means of selecting patients who will benefit from pyeloplasty.