DECT Study in Allopurinol-Treated Gout Patients

The purpose of this study is to determine presence and volume of monosodium urate (MSU) crystal deposits as determined by dual-energy computed tomography (DECT) imaging in gout subjects treated with allopurinol with and without visible tophi.

DECT is a technique that enables visualization of MSU crystal deposits by analysis of the chemical composition of the scanned materials. This study will determine the extent of MSU crystal volume in the hands/wrists, feet/ankles, and knees as determined by DECT of subjects with gout taking a dose of at least 300 mg allopurinol daily for the past 12 weeks. Patients with gout on allopurinol with and without tophi to be assessed using DECT imaging for crystal deposition with assessments, which include patient and provider assessments of disease severity and pain, prior to and after the scan.