False positive I-131 total body scan due to bilateral polycystic renal disease

A radioiodine accumulation at Total Body Scan (TBS) in patient who has been thyroidectomized for a differentiated thyroid cancer is usually a reliable indicator of recurrent or metastatic functioning thyroid tissue. Radioiodine uptake may be usually observed at TBS in areas such as the intestinal tract, liver, salivary glands, bladder, and also in case of blood vessel ectasia. This report describes a patient with a bilaterally significant I-131 uptake in upper abdomen. By ultrasound and radionuclide imaging the I-131 uptake was proven to be due to radioiodine accumulation caused by bilateral polycystic renal disease. (C) 1997, Editrice Kurtis.