FDG-PET of patients with suspected renal failure: standardized uptake values in normal tissues

This study aims to clarify the effect of renal function on 2-[(18)F] fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) imaging and determine the clinical significance of renal function in this setting. We compared FDG distribution between normal volunteers and patients with suspected renal failure.

Twenty healthy volunteers and 20 patients with suspected renal failure who underwent FDG-PET between November 2002 and May 2005 were selected for this study. We define "patients with suspected renal failure" as having a blood serum creatinine level in excess of 1.1 mg/dl. The serum creatinine level was examined once in 2 weeks of the FDG-PET study. Regions of interest were placed over 15 regions for semi-quantitative analysis: the white matter, cortex, both upper lung fields, both middle lung fields, both lower lung fields, mediastinum, myocardium of the left ventricle, the left atrium as a cardiac blood pool, central region of the right lobe of the liver, left kidney, and both femoris muscles.

The mean standardized uptake values (SUVs) of brain cortex and white matter were higher in healthy volunteers than in renal patients. The mean SUVs of the mediastinum at the level of the aortic arch and left atrium as a cardiac blood pool were lower in healthy volunteers than in patients with suspected renal failure. These regions differed between healthy volunteers and patients with suspected renal failure (P < 0.05).

We found decreasing brain accumulation and increasing blood pool accumulation of FDG in patients with high plasma creatinine. Although the difference is small, this phenomenon will not have a huge effect on the assessment of FDG-PET imaging in patients with suspected renal failure.