Clinical utility of dual-energy CT for gout diagnosis.

OBJECTIVE: The present study was to evaluate the clinical value of dual-energy computed tomography (DECT) for detecting monosodium urate crystals in patients with gouty arthritis.

METHODS: Two hundred and two patients, who experienced arthrocele and (or) joint pain, were enrolled into our study. DECT scans of upper or lower extremity were performed. One hundred and sixty one patients who conformed to the American College of Rheumatology classification standard were defined as the gout group. The rest (41) of the patients were regarded as the without-gout group. DE (80kV/140kV) datasets were reconstructed via DE gout software. Images were reviewed independently by two senior radiologists.

RESULTS: In the gout group, DECT scans revealed a total of 379 areas of urate deposition in 121 patients. In the without-gout group, 3 areas of green urate deposition were detected. The sensitivity and specificity were 75.2% and 92.7%, respectively; when we increased the ratio to 1.32 and decreased the range to 3, the number of patients with green urate deposition increased, and the areas of urate deposition were more extensive. The sensitivity and specificity were 91.9% and 85.4%. DECT images could illustrate the palpable reduction in the tissue urate deposits compared to baseline images before and after treatment.

CONCLUSIONS: DECT has comparable sensitivity and specificity for the detection of gouty arthritis in a clinical setting, and DECT can monitor the clinical treatment. However, DECT results should be interpreted carefully because there could be some false-negative or false-positive findings.