Department of Rheumatology and Immunology, The First Affiliated Hospital of Anhui Medical University, Hefei, China.
Immun Inflamm Dis. 2023 Jun;11(6):e882. doi: 10.1002/iid3.882.
The objective of this study is to investigate clinical features and prognostic factors of antimelanoma differentiation-associated gene 5 (anti-MDA5)-positive dermatomyositis with rapidly progressive interstitial lung disease (RP-ILD) in Chinese patients.
Clinical features and prognostic factors of patients with newly diagnosed or recurrent dermatomyositis patients were retrospectively analyzed. All patients were divided into the anti-MDA5-positive or negative dermatomyositis, and with or without RP-ILD groups. Clinical features and prognostic factors were statistically compared among different groups.
The serum ferritin (SF) levels (1500.0 [658.80, 1844.0]) and γ-glutamyl transpeptidase (γ-GT) (125.5 [61.0, 232.0] vs. 28 [16.0, 41.0], Z = 5.528; p < .001) were markedly higher, and phosphocreatine myoenzyme (CK) (73.0 [42.0, 201.0] vs. 1333.0 [79.0, 8000.0], Z = -2.739, p = .006), serum albumin level (32.51 ± 5.23 vs. 35.81 ± 5.88, t = -2.542, p = .013), and lymphocyte count (0.80 ± 0.36 vs. 1.45 ± 0.77, t = -4.717, p < .001) were lower than those in anti-MDA5-negative counterparts. Among patients with anti-MDA5 antibody (Ab) with RP-ILD, the SF level (1531.0 [1163.8, 2016.5] vs. 584.9 [564.8, 1042.5], Z = 2.664, p = .008), γ-GT (134.0 [81.0, 204.5] vs. 123.0 [76.0, 189.0], Z = 3.136, p = .002) and positive rate of anti-RO-52 Ab (90.9% vs. 50.0%, χ = 7.222, p = .013) were higher and lymphocyte count (0.79 ± 0.38 vs. 1.32 ± 0.74, t = -3.025, p = .029) was lower than those in their counterparts without RP-ILD. The SF level of anti-MDA5 nonsurvivors (1544 [1447.32, 2089.0] vs. 584.9 [515.7, 1500.0], Z = 2.096, p = .030), anti-RO-52 Ab-positive rate ([16/18, 88.9%] vs. [9/16, 56.2%], χ = 4.636, p = .031) were higher than those in survivors. Lymphocytopenia was a risk factor for RP-ILD and death of patients with anti-MDA5-positive dermatomyositis. The area under receiver operating characteristic curve was 0.888 (95% confidence interval: 0.756, 1.000; p < .001), the sensitivity was 85.7%, the specificity was 93.8%, and Youden's index was 0.795.
Anti-MDA5-positive dermatomyositis patients are prone to developing RP-ILD. Declined lymphocyte count is a critical risk factor for RP-ILD, probably acting as a simple and effective predictor for Chinese patients with anti-MDA5-positive dermatomyositis.
本研究旨在探讨中国抗黑色素瘤分化相关基因 5（anti-MDA5）阳性皮肌炎伴快速进展性间质性肺病（RP-ILD）患者的临床特征和预后因素。
回顾性分析新诊断或复发性皮肌炎患者的临床特征和预后因素。所有患者均分为抗-MDA5 阳性或阴性皮肌炎组，以及伴或不伴 RP-ILD 组。对不同组间的临床特征和预后因素进行统计学比较。
血清铁蛋白（SF）水平（1500.0[658.80, 1844.0]）和γ-谷氨酰转肽酶（γ-GT）（125.5[61.0, 232.0]）明显高于抗-MDA5 阴性组（28[16.0, 41.0]），差异有统计学意义（Z=5.528;p<0.001），而磷酸肌酸同工酶（CK）（73.0[42.0, 201.0]）和血清白蛋白水平（32.51±5.23）明显低于抗-MDA5 阴性组（1333.0[79.0, 8000.0]），差异有统计学意义（Z=-2.739;p=0.006），差异有统计学意义（Z=-2.664;p=0.008），γ-GT（134.0[81.0, 204.5]）和抗-RO-52 Ab 阳性率（90.9%）明显高于抗-MDA5 阴性组（123.0[76.0, 189.0]），差异有统计学意义（Z=3.136;p=0.002），差异有统计学意义（χ 2=7.222;p=0.013），差异有统计学意义（χ 2=4.636;p=0.031）。抗-MDA5 阴性患者的淋巴细胞计数（0.79±0.38）明显低于抗-MDA5 阴性患者（1.32±0.74），差异有统计学意义（t=-3.025;p=0.029）。抗-MDA5 死亡患者的 SF 水平（1544[1447.32, 2089.0]）明显高于存活患者，差异有统计学意义（Z=2.096;p=0.030），抗-RO-52 Ab 阳性率（16/18，88.9%）明显高于存活患者，差异有统计学意义（χ 2=4.636;p=0.031）。淋巴细胞减少是抗-MDA5 阳性皮肌炎患者发生 RP-ILD 和死亡的危险因素。受试者工作特征曲线下面积为 0.888（95%可信区间：0.756, 1.000;p<0.001），敏感性为 85.7%，特异性为 93.8%，Youden 指数为 0.795。
抗-MDA5 阳性皮肌炎患者易发生 RP-ILD。淋巴细胞减少是发生 RP-ILD 的关键危险因素，可能是中国抗-MDA5 阳性皮肌炎患者的一个简单有效的预测指标。
