Pitfalls and limitations of diuretic renography.

We report five pediatric cases that illustrate the methodologic pitfalls and limitations of diuretic renography in suspected ureteropelvic junction obstruction. False-positive studies may be related to such avoidable flaws in methodology as premature diuretic administration, inadequate diuretic dose, and bladder distension, or to recent pyeloplasty. False-negative results may occur despite optimum technique, necessitating a follow-up study for confirmation.