Abstract: Objective To study the value of dual energy computed tomography（DECT）imaging and serum interleukin-1β (IL-1β) levels in the diagnosis of gout. Methods A total of 76 patients with gout treated in immunity department of Tianjin First Center Hospital from June 2015 to June 2016 were included in this study (gout group). Another 40 non-gout patients including 33 cases with rheumatoid arthritis and 7 cases with osteoarthritis were served as control group. DECT were used to detect the damaged joints of patients, and confirm the number and the position of uratecrystal. Enzyme-linked immunosorbent assay (ELISA) was used to detect the serum levels of IL-1β in two groups. Receiver operating characteristic (ROC) curves of IL-1β were plotted to determine the area under the curve (AUC) and the best cut- off value. Results DECT scan found 349 lesions with urate deposition, mainly located at the first metatarsophalangeal joint (n=245). Five false-positive patients were detected in control group, in which 3 were perionychia pseudoshadow and 2 were foot pad pseudoshadow. The sensitivity and specificity of DECT were 100% and 87.5%, while which of IL-1β were 65.7% and 90.0%. The sensitivity and specificity of combined detection DECT and IL-1β were 100% and 95.0%. The AUC measured by IL-1β was 0.929 (0.882-0.977), and the best cut-off value of the indicator was 5 ng/L. Conclusion DECT combined with serum IL-1β detection can help for the early diagnosis of gout, and accurately location of uric acid， which has high clinical value.

Key words: gout, interleukin-1beta, diagnosis, dual-energy computer tomography