Anterior position of the lower pole of the right kidney: Potential confusion with right upper quadrant mass

A group of patients with anterior position of the lower pole of the right kidney were examined with ultrasound to evaluate a palpable right upper quadrant mass. After it was determined, with the use of ultrasound, that the palpable mass represented the kidney, no further evaluations were necessary. This appearance is seen fairly often in normal individuals and should be considered a normal variant. The possible anatomic explanation for this appearance is discussed.