Dual-Energy Computed Tomography Has Additional Prognostic Value Over Clinical Measures in Gout Including Tophi: A Systematic Literature Review

Abstract

Objective This Systematic Literature Review determined whether there is clinical utility for Dual Energy CT (DECT) to inform on prognosis for gout patients. With DECT, individualized treatment plans could be developed based on the patient's unique urate burden, with DECT used as a clinical outcome measure in gout management. Methods To evaluate DECT as a reliable, valid, and sensitive prognostic instrument, a librarian-assisted search was undertaken in PubMed and EMBASE for articles on gout and DECT informing on reliability, validity (content, construct, criterion), sensitivity to change and minimum clinically important changes. Results This systematic literature review showed that DECT has high intra- and inter-rater reliability. Tophus burden correlates with functional loss to show content validity. DECT volume is positively correlated with death and cardiovascular risk factors, and the risk for future gout flares. DECT has excellent sensitivity to change with effective urate lowering therapies. Conclusion DECT is a promising prognostic tool based on its high reliability, sensitivity to change, and emerging validity. Additional large, well-designed prospective cohort studies are needed to fully evaluate its prognostic utility. This systematic review suggests it's very likely DECT has additional prognostic information beyond clinical tophi assessment alone.

Advanced Imaging of Gout and Other Inflammatory Diseases Around the Knee

“…13 A systematic review in 2022 showed that DECT images are reliably interpreted with intra-rater intraclass correlation coefficients ranging from 0.86 to 1.00. 30 DECT overall had very good sensitivity and specificity in established gout when compared with joint aspiration, with ranges from 0.78 to 0.89 and 0.84 to 1.00, respectively. DECT also performed very well against clinical criteria, with a pooled sensitivity and specificity of 0.81 (95% confidence interval [CI], 0.77–0.86) and 0.91 (95% CI, 0.85–0.95).…”

“…DECT also performed very well against clinical criteria, with a pooled sensitivity and specificity of 0.81 (95% confidence interval [CI], 0.77-0.86) and 0.91 (95% CI, 0.85-0.95). 30 A study comparing the diagnostic accuracies of dualsource DECT and US in patients with different gouty disease durations reported that the sensitivities of DECT for gout within 1 year, 1 to 3 years, and > 3 years are 26.6%, 66.6%, and 90%, respectively. 31 They also revealed that the sensitivity of US is remarkably higher than that of dual-source DECT in early gout and suggested US as the first choice to diagnose early-stage gout.…”

“…33 DECT may be used to stage patients with gout, especially in established disease, because 50% of patients have abnormal DECT scans with normal serum urate levels and no clinical tophi. 30 Other applications of DECT include prediction of disease flares at 6 months and 2 years and excess cardiovascular and all-cause mortality. 30…”

“…30 Other applications of DECT include prediction of disease flares at 6 months and 2 years and excess cardiovascular and all-cause mortality. 30…”

“…DECT also performed very well against clinical criteria, with a pooled sensitivity and specificity of 0.81 (95% confidence interval [CI], 0.77–0.86) and 0.91 (95% CI, 0.85–0.95). 30…”