Dual-Energy CT Scan (DECT)
Next, Dr. Thiele directed our attention toward DECT, a type of imaging that uses differences in attenuation at different energies to help differentiate calcium from urate crystals. “DECT can provide three-dimensional reconstructional imaging so you can really get an overview of where the tophi are located, but it can underestimate tophus size when compared with ultrasound,” he explained.5 “With DECT you need a certain concentration of tophaceous material per cubic space for it to be detected. So, patients with early tophaceous disease might be missed on DECT, and better appreciated with ultrasound. Ultrasound provides anatomic context and also demonstrates hyperemic inflammation, but it can miss tophi if the location is not included in the routine scanning protocol. DECT provides more of a general overview.”
Which modality should we choose? “Sensitivity and specificity are overall comparable between the two.6 So I recommend considering availability, cost, patient comfort and repeatability of imaging when deciding between ultrasound and DECT,” Dr. Thiele concluded.
Gout & CV Disease
Dr. Choi spoke next, shifting the talk toward gout and CV comorbidities. Gout prevalence continues to increase, largely driven by hyperuricemia associated with western lifestyle trends. Worsening comorbidities at the time of incident gout have increased as well, with hypertension (74%), metabolic syndrome (63%) and obesity (53%) topping the list.7 There is an independent association between serum uric acid concentration and the risk of CV disease, though causation remains unclear.
What can we do? “While the causality between urate levels, CV disease and gout remains debated and trials are ongoing, we still need to do our best to treat gout and protect our patients,” Dr. Choi said. “It would be best if we could find a medication that protected against gout and CV disease so we could reverse premature mortality trends in our gout patients.”
Recent studies have shown CV disease-protective effects from colchicine and interleukin-1 inhibition.8,9 In addition, sodium-glucose cotransporter-2 (SLGT-2) inhibitors have shown pleiotropic benefits in chronic kidney disease, and may also offer benefits relevant to gout.10 Dr. Choi hopes further studies will better elucidate how we can use medications as a “two for one.”
Dr. Choi next discussed the much-debated CV risk of xanthine oxidase inhibitors. In 2018, the CARES trial showed an increased risk of cardiac and all-cause mortality with febuxostat, resulting in an U.S. Food & Drug Administration (FDA) boxed warning for an increased risk of death.11 In 2020, data from the FAST trial contradicted those results, showing no increased risk.12