Advantage of indium-111 leukocytes over ultrasound in imaging an infected renal cyst.

Indium-111-labeled leukocyte scanning is a highly sensitive and specific method of detecting abscesses. This report describes a patient with polycystic kidneys and a single infected cyst. Ultrasound could not determine which cyst was infected, but the infected cyst could be localized by [111In]leukocyte imaging in conjunction with a [99mTc]DMSA renal scan. The two radionuclide studies were used to identify an infected renal cyst and direct ultrasound guided aspiration.