Laurent Victor, Jauffret Charlotte, Ducoulombier Vincent, Pacaud Aurore, Legrand Julie, Verdun Stéphane, Norberciak Laurène, Budzik Jean-François, Pascart Tristan
Department of Rheumatology, Hôpital Saint-Philibert, Université Catholique de Lille, Lomme, France.
Department of Radiology, Hôpital Saint-Philibert, Université Catholique de Lille, Lomme, France.
Rheumatology (Oxford). 2025 Feb 1;64(2):581-587. doi: 10.1093/rheumatology/keae061.
To determine the clinical associations and predictive value of two thresholds of negative dual-energy CT (DECT) for MSU crystal deposition in gout patients initiating urate-lowering therapy (ULT) and identify which threshold is more clinically relevant.
Patients from the CRYSTALILLE cohort with a diagnosis of gout naïve to ULT with baseline DECT scans of the knees and feet were selected. Two thresholds of positivity for DECT detection of MSU crystal deposition were considered (<0.01 cm3 and <0.1 cm3). Baseline characteristics and the prediction of key outcomes after ULT initiation, including reaching serum urate (SU) levels <6.0 and 5.0 mg/dl and occurrence of flares at 6, 12 and 24 months, associated with both thresholds of negative DECTs were compared with those of patients having positive DECT scans.
A total of 211 patients, median age 66.2 years [interquartile range (IQR) 57-75.8], with a median symptom duration of 3 years (IQR 0-7.8) were included. A total of 38/211 (18%) and 90/211 (43%) had negative DECT scans for the 0.01 and 0.1 cm3 thresholds, respectively. Factors associated with negative DECT scans were younger age, shorter symptom duration and an absence of cardiovascular disease for both volume thresholds. A total of 9/39 (23.1%), 3/26 (11.5%) and 1/18 (5.6%) patients with <0.1 cm3 MSU crystals had flares at 6, 12 and 24 months, respectively, compared with 18/45 (40.0%), 9/36 (25.0%) and 2/18 (11.1%) patients with ≥0.1 cm3 (P > 0.05). Overall, 95 patients (68.3%) reached SU levels <6.0 mg/dl and 68 (48.9%) reached levels <5.0 mg/dl, without any difference between positive and negative DECTs, with ULT dosages that tended to be lower in patients with negative DECTs.
The 0.1 cm3 threshold was better correlated with clinical presentation and evolution than the 0.01 cm3 threshold. Gout patients with negative DECTs exhibit milder disease and a lower comorbidity burden. They do not exhibit particularly easy-to-treat hyperuricaemia but they may have a lower risk of flares.
确定痛风患者开始降尿酸治疗（ULT）时，双能量CT（DECT）检测MSU晶体沉积的两个阴性阈值的临床相关性和预测价值，并确定哪个阈值在临床上更具相关性。
从CRYSTALILLE队列中选取初诊痛风且未接受ULT治疗、有膝关节和足部基线DECT扫描的患者。考虑DECT检测MSU晶体沉积的两个阳性阈值（<0.01 cm³和<0.1 cm³）。比较基线特征以及ULT开始后关键结局的预测情况，包括血清尿酸（SU）水平降至<6.0和5.0 mg/dl以及6、12和24个月时痛风发作情况，将DECT阴性的两个阈值与DECT扫描阳性的患者进行比较。
共纳入211例患者，中位年龄66.2岁[四分位间距（IQR）57 - 75.8]，中位症状持续时间3年（IQR 0 - 7.8）。对于0.01 cm³和0.1 cm³的阈值，分别有38/211（18%）和90/211（43%）的患者DECT扫描为阴性。与DECT扫描阴性相关的因素在两个体积阈值下均为年龄较小、症状持续时间较短且无心血管疾病。MSU晶体<0.1 cm³的患者在6、12和24个月时痛风发作的分别有9/39（23.1%）、3/26（11.5%）和1/18（5.6），而MSU晶体≥0.1 cm³的患者分别为18/45（40.0%）、9/36（25.0%）和2/18（11.1%）（P>0.05）。总体而言，95例患者（68.3%）的SU水平降至<6.0 mg/dl，68例（48.9%）降至<5.0 mg/dl，DECT阳性和阴性患者之间无差异，DECT阴性患者的ULT剂量往往较低。
与0.01 cm³阈值相比，0.1 cm³阈值与临床表现和病情演变的相关性更好。DECT阴性的痛风患者疾病较轻，合并症负担较低。他们没有表现出特别易于治疗的高尿酸血症，但痛风发作风险可能较低。
