抗信号识别颗粒抗体阳性的皮肌炎/临床无肌病性皮肌炎患者临床特点分析

【摘要】 目的 分析血清抗信号识别颗粒（SRP）抗体阳性的皮肌炎/临床无肌病性皮肌炎（DM/CADM）患者的临床特点。方法 收集2015年6月至2017年7月上海交通大学医学院附属瑞金医院皮肤科病房收治的90例DM/CADM患者的临床资料，用免疫印迹法检测患者血清抗SRP抗体。采用t检验和χ2检验等方法进行统计学分析。结果 90例DM/CADM患者中11例（12.2%）血清抗SRP抗体阳性，其中6例DM，5例CADM。82例成人DM/CADM患者中，抗SRP抗体阳性合并恶性肿瘤的发生率显著高于抗SRP抗体阴性患者［7/9比31.5%（23/73），χ2 = 7.394，P = 0.006］。11例抗SRP抗体阳性患者均有DM典型皮疹，DM皮损面积和严重指数为18.1 ± 2.9。抗SRP抗体阳性患者翼状征的发生率显著高于抗体阴性患者［7/11比29.9%（20/67），Fisher精确检验，P = 0.028］。抗SRP抗体阳性患者抗核抗体阳性率显著高于抗体阴性患者［4/8比16.7%（13/78），χ2 = 6.053，P = 0.014］。10例抗SRP抗体阳性患者（6例DM和4例CADM）行双大腿肌肉磁共振检查，其中8例肌群内信号异常，肌群肿胀2例，皮下水肿2例，肌筋膜肿胀1例，仅2例无异常。抗SRP抗体阳性患者均无肺间质病变和心肌受累。结论 抗SRP抗体阳性DM/CADM患者躯干翼状征发生率高，合并恶性肿瘤的风险显著增加。DM/CADM患者在病程早期检测抗SRP抗体水平有助于预测恶性肿瘤的发生。

Clinical features of anti-signal recognition particle antibody-positive patients with dermatomyositis or clinically amyopathic dermatomyositis

【Abstract】 Objective To investigate the clinical features of anti-signal recognition particle （SRP）antibody-positive patients with dermatomyositis/clinically amyopathic dermatomyositis（DM/CADM）. Methods Clinical data were collected from 90 patients with DM/CADM, who were hospitalized at the Department of Dermatology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine from June 2015 to July 2017. Immunoblotting assay was performed to determine the serum level of anti-SRP antibody in these patients. Statistical analysis was carried out using t test and Chi-square test. Results Of the 90 patients with DM/CADM, 11 （12.2%） were positive for serum anti-SRP antibody, including 6 with DM and 5 with CADM. Among 82 adult patients with DM/CADM, the prevalence of malignant tumors was significantly higher in the patients with anti-SRP antibody than in those without （7/9 vs. 31.5% ［23/73］, χ2 = 7.394, P = 0.006）. The 11 patients with anti-SRP antibody had typical DM skin lesions, and their cutaneous dermatomyositis disease area and severity index（CDASI）was 18.1 ± 2.9. The prevalence of “angel wings sign” （aliform erythema on the trunk） was significantly higher in the patients with anti-SRP antibody than in those without （7/11 vs. 29.9% ［20/67］, Fisher′s exact test, P = 0.028）. The positive rate of antinuclear antibody was significantly higher in the patients with anti-SRP antibody than in those without （4/8 vs. 16.7% ［13/78］, χ2 = 6.053, P = 0.014）. Magnetic resonance imaging of muscles of both thighs of the 10 patients with anti-SRP antibody （6 with DM and 4 with CADM） showed the presence of abnormal signals in the thigh muscle group in 8, swelling of the muscle group in 2, subcutaneous edema in 2, myofascial swelling in 1, and no abnormities in 2. No interstitial lung disease or myocardial involvement was observed in the patients with anti-SRP antibody. Conclusions The anti-SRP antibody-positive patients with DM/CADM showed a high prevalence of “angel wings sign”, and a high risk of malignant tumors. Early detection of the anti-SRP antibody in patients with DM/CADM is helpful to predict the occurrence of malignant tumors.