Medicine Service, Birmingham Veterans Affairs (VA) Medical Center.
Department of Medicine at School of Medicine.
Rheumatology (Oxford). 2021 Oct 2;60(10):4861-4867. doi: 10.1093/rheumatology/keaa923.
To examine the accuracy of dual-energy CT (DECT) vs ultrasound or their combination for the diagnosis of gout.
Using prospectively collected data from an outpatient rheumatology clinic at a tertiary-care hospital, we examined the diagnostic accuracy of either modality alone or their combination, by anatomical site (feet/ankles and/or knees), for the diagnosis of gout. We used two standards: (i) demonstration of monosodium urate crystals in synovial fluid (gold), and (ii) modified (excluding DECT and ultrasound) 2015 ACR-EULAR gout classification criteria (silver).
Of the 147 patients who provided data, 48 (33%) had synovial fluid analysis performed (38 were monosodium urate-crystal positive) and mean symptom duration was 9.2 years. One hundred (68%) patients met the silver standard. Compared with the gold standard, diagnostic accuracy statistics for feet/ankles DECT, feet/ankles ultrasound, knees DECT and knees ultrasound were, respectively: sensitivity: 87%, 84%, 91% and 58%; specificity: 100%, 60%, 87% and 80%; positive predictive value: 100%, 89%, 97% and 92%; negative predictive value: 67%, 50%, 70% and 33%; area under the receiver operating characteristic curve: 0.93, 0.72, 0.89 and 0.66. Combining feet/ankles DECT with ultrasound or knees DECT with ultrasound led to a numerically higher sensitivity compared with DECT alone, but overall accuracy was lower. Similarly, combining imaging knees to feet/ankles also yielded a numerically higher sensitivity and negative predictive values compared with feet/ankles DECT alone, without differences in overall accuracy. Findings were replicated compared with the silver standard, but with lower numbers.
Feet/ankles or knees DECT alone had the best overall accuracy for gout diagnosis. The DECT-US combination or multiple joint imaging offered no additional increase in overall diagnostic accuracy.
研究双能 CT（DECT）与超声或两者联合应用在诊断痛风中的准确性。
我们利用一家三级医院门诊风湿病诊所前瞻性收集的数据，通过解剖部位（足部/踝关节和/或膝关节），单独或联合使用这两种方法（DECT 和超声）检测痛风的诊断准确性。我们使用了两种标准：（i）关节液中发现单钠尿酸盐晶体（金标准），以及（ii）改良（不包括 DECT 和超声）2015 年 ACR-EULAR 痛风分类标准（银标准）。
在提供数据的 147 名患者中，48 名（33%）进行了关节液分析（38 例为单钠尿酸盐结晶阳性），平均症状持续时间为 9.2 年。100 名（68%）患者符合银标准。与金标准相比，足部/踝关节 DECT、足部/踝关节超声、膝关节 DECT 和膝关节超声的诊断准确性统计数据分别为：敏感性：87%、84%、91%和 58%；特异性：100%、60%、87%和 80%；阳性预测值：100%、89%、97%和 92%；阴性预测值：67%、50%、70%和 33%；受试者工作特征曲线下面积：0.93、0.72、0.89 和 0.66。与单独使用 DECT 相比，将足部/踝关节 DECT 与超声或膝关节 DECT 与超声联合使用可提高敏感性，但整体准确性较低。同样，将膝关节成像与足部/踝关节成像相结合也可提高敏感性和阴性预测值，而不会影响整体准确性。与银标准相比，结果是可复制的，但数量较低。
单独使用足部/踝关节或膝关节 DECT 对痛风诊断具有最佳的整体准确性。DECT-US 联合应用或多关节成像并未提高整体诊断准确性。
