肌炎特异性抗体在多发性肌炎和皮肌炎中的意义

目的测定多发性肌炎（PM）/皮肌炎（DM）患者血清中肌炎特异性抗体（MSA）及肌炎相关性抗体（MAA）的阳性率,探讨MSA在PM/DM中的意义.方法PM/DM患者31例,用免疫印迹法检测血清MSAs和MAAs阳性率,分析患者的临床表现及预后与自身抗体的相关性.结果31例患者中18例出现MSAs和/或MAAs阳性（58%）,其中MSAs阳性率为39%,最常见的MSAs是抗Jo-1抗体（29%）,其次是抗Mi-2抗体（6%）,抗PL-7抗体（3%）,抗PL-12抗体（3%）,MAAs的阳性率为32%,其中抗Ku-72占.16%,抗Ku-86占23%,抗PM-Scl抗体占6%.肺间质病变及关节炎/痛在抗Jo-1抗体阳性患者中的比例明显高于抗Jo-1抗体阴性组（P＜0.05）.治疗后18例患者完全缓解,12例部分缓解,1例死亡.随访12例患者,在激素减量后均有复发,MSAs阳性与阴性组间复发次数、病死率无明显差别.肺间质纤维化在MSAs阳性患者中发生率较高,预后较差.结论MSAs和MAAs在PM/DM患者中阳性表达率较高,MSAs与PM/DM的临床表现和预后相关.开展MSAs及MAAs的测定对于PM/DM临床诊断和治疗有重要意义.     

血清抗氨酰tRNA合成酶抗体检测在特发性炎性肌病伴间质性肺疾病中的意义

目的 检测多发性肌炎/皮肌炎患者血清抗氨酰tRNA合成酶(ARS)抗体水平,并与抗Jo-1抗体相比较,探讨其在特发性炎性肌病伴间质性肺疾病(ILD)中的意义.方法 采用酶联免疫吸附试验(ELISA)法测定109例多发性肌炎/皮肌炎患者,20例系统性红斑狼疮(SLE)患者,20例类风湿关节炎(RA)患者以及30名健康对照组血清中抗ARS抗体水平及阳性率.使用t检验、Mann-Wittney U检验、X2检验及Fisher精确检验分析ARS阳性患者的临床特点.使用McNemar检验比较抗ARS抗体和抗Jo-1抗体对诊断多发性肌炎/皮肌炎合并ILD的敏感性及特异性.结果 血清抗ARS抗体的阳性率在合并ILD的多发性肌炎/皮肌炎组、未合并ILD的多发性肌炎/皮肌炎组、SLE组、RA组及健康对照组分别是37.9％、7.8％、10％、0和0.合并ILD的多发性肌炎/皮肌炎组血清抗ARS抗体阳性率较未合并ILD的多发性肌炎/皮肌炎组、SLE组、RA组和健康对照组均显著升高(X2-13.5,5.45,10.57,15.17;P＜0.01).抗ARS抗体诊断多发性肌炎/皮肌炎合并ILD的敏感性显著高于抗Jo-1抗体(37.9％比17.2％,P＜0.01),而两者特异性差异无统计学意义(P＞0.05).抗ARS抗体阳性患者发热、ILD发生率较抗ARS抗体阴性患者显著升高(X2=12.55,13.53;均P＜0.01),而披肩征及向阳疹的发生率则低于ARS阴性组(X2=5.7,5.8;P均＜0.05).抗ARS抗体阳性组同抗Jo-1抗体阳性组间临床特点差异无统计学意义(P均＞0.05).随访发现多发性肌炎/皮肌炎合并ILD死亡患者血清抗ARS抗体均为阴性.结论 相较抗Jo-1抗体而言,血清抗ARS抗体检测对多发性肌炎/皮肌炎伴ILD的诊断敏感性更高,有利于早期诊断,值得临床推广应用.     

抗Jo-1抗体在多发性肌炎/皮肌炎中的临床研究

目的摇对69例多发性肌炎/皮肌炎(PM/MD)病人抗Jo-1抗体进行检测,了解抗Jo-1抗体阳性与PM/DM临床症状的相关性及对PM/DM的诊断价值。方法应用免疫印迹(IBT)法检测PM/DM病人中的抗Jo-1抗体,对抗Jo-1抗体阳性血清进行免疫双扩散(ID)检测,两者抗Jo-1抗体均阳性者为抗Jo-1抗体阳性组,其他为抗Jo-1抗体阴性组,前瞻性比较PM/DM抗Jo-1抗体阳性组和抗Jo-1抗体阴性组的临床特征。结果本组中抗Jo-1抗体阳性占32%,抗Jo-1抗体阳性患者出现肺间质病变(ILD)、多关节炎/多关节痛、肺部感染和雷诺现象分别为18例(82%)、18例(82%)、17例(77%)、7例(32%);与抗Jo-1抗体阴性组比较,差异有显著性(P<0.05)。另外,在阳性组出现吞咽困难1例(5%),而阴性组为15例(32%),两组相比差异有显著性(P<0郾05)。结论抗Jo-1抗体阳性组PM/DM患者的肺间质病变及多关节炎症状突出,合并肺部感染的概率高,而肌痛或肌无力症状较轻,出现吞咽困难症状概率较低;阴性组出现吞咽困难症状概率较阳性组高。     

汉族多发性肌炎/皮肌炎患者抗合成酶抗体谱及其临床意义

目的探讨汉族多发性肌炎皮肌炎(polymyositisdermatomyositis,PMDM)患者抗合成酶(aminoacyl-transfer RNA synthetase,ARS)抗体谱的分布及其临床意义。方法采用核酸免疫沉淀法对145例汉族PMDM患者进行抗ARS抗体检测,并收集阳性患者临床资料。采用t检验、Mann-Whitney U检验、χ2检验或Fisher’s精确概率法进行统计学分析。结果 145PMDM例患者中,40例(27.6%)抗ARS抗体阳性,其中抗Jo-1抗体阳性24例,非Jo-1抗ARS阳性16例(包括抗EJ 7例、抗OJ 5例、抗KS 3例和抗PL-12抗体1例)。抗Jo-1抗体阳性组中PM比例高于非Jo-1抗ARS阳性患者组,差异有统计学意义(87.5%vs.43.8%,P=0.003);但2组性别和发病年龄分布类似;发热、雷诺现象、关节痛、技工手、间质性肺疾病和吞咽困难发生率及肌酸激酶水平在抗Jo-1抗体组[分别为54.2%、16.7%、25.0%、33.3%、91.7%、4.2%和(3 041±4 351)UL]和非Jo-1抗ARS组[分别为43.8%、31.3%、37.5%、25.0%、100.0%、18.8%和(861±820)UL]间差异无统计学意义(P0.05)。结论汉族PMDM患者非Jo-1抗ARS抗体并不少见,其临床表现与抗Jo-1抗体阳性患者相似。     

多发性肌炎和皮肌炎血清抗Jo-1抗体水平与疾病活动度相关性研究

目的 探讨抗Jo-1抗体水平与多发性肌炎/皮肌炎疾病活动度的相关性.方法 采用免疫印迹法和酶联免疫吸附试验(ELISA)法检测148例多发性肌炎/皮肌炎患者和性别年龄相匹配的130名健康人血清抗Jo-1抗体水平,利用国际肌炎组织制定的炎性肌病评价工具评估抗Jo-1抗体阳性患者疾病活动度(VAS),并分析抗Jo-1抗体水平与多发性肌炎肢肌炎疾病活动度的相关性.统计学处理采用x2检验或t检验.结果 免疫印迹法和ELISA法检测多发性肌炎/皮肌炎患者血清抗Jo-1抗体的阳性率分别是24.3％(36/148)和27.0％(40/148),健康人血清中抗Jo-1抗体均为阴性.发热、肺间质病变(ILD)和关节炎/关节痛在抗Jo-1抗体阳性组的比例明显高于抗Jo-1抗体的阴性组(P＜0.05).抗Jo-1抗体阳性患者的总疾病活动度评分与血清抗Jo-1抗体的浓度呈正相关(r=0.874,P=0.000).7例患者治疗后患者血清抗Jo-1抗体浓度与疾病活动度评分均显著下降,两者变化一致.结论 ELISA法检测抗Jo-1抗体水平与疾病活动相关,可作为多发性肌炎/皮肌炎疾病活动的评价指标.     

B细胞刺激因子在特发性炎性肌病相关肺间质病变的临床意义

目的 探究B细胞刺激因子(BAFF)在特发性炎性肌病(IIM)相关肺间质病变(ILD)中的临床意义。方法 纳入122例IIM患者,其中86例并发ILD,按性别、年龄匹配40例正常人作为对照,采用酶联免疫吸附试验检测BAFF,分析其临床意义。结果 与non-ILD组相比,IIM-ILD组BAFF水平显著升高[2.19(1.07～4.54) ng/mL vs.1.14(0.61～2.30) ng/mL,P=0.005],是IIM-ILD的独立危险因素。抗MDA5抗体及抗合成酶抗体(ASA)阳性的IIM患者BAFF水平显著高于双阴性患者(P<0.05)。BAFF>3.74 ng/mL时,对于诊断IIM-ILD的敏感性为36.0%,特异性为97.2%(AUC=0.681,P=0.002);联合KL-6时,对于诊断IIM-ILD的敏感性为82.6%,特异性为80.6%(AUC=0.868,P<0.001)。BAFF与铁蛋白呈正相关(r=0.368,P<0.001),与KL-6、肺部HRCT评分、肺功能无明显相关性。结论 BAFF在IIM-ILD患者中显著升高,可作为IIM...     

肌炎相关间质性肺病的治疗进展

特发性炎性肌病(IIMs)是一种影响肌肉和肌肉外组织器官的自身免疫病。间质性肺病(ILD)是IIMs的主要肌肉外受累表现, 与PM、DM和临床无肌病性皮肌炎(CADM)病死率增加相关。最近的研究强调了肌炎特异性自身抗体(MSAs)的重要性, 特别是抗黑色素瘤分化相关基因5(MDA5)抗体和抗氨基酰tRNA合成酶(ARS)抗体。由于抗MDA5抗体的存在是预后较差的一个强有力的预测因素, 对于抗MDA5抗体阳性DM/CADM合并ILD(DM/CADM-ILD)患者, 推荐使用糖皮质激素(GC)和钙调神经磷酸酶抑制剂(CNIs)(他克莫司或环孢素A)联合治疗。尤其是快速进展性DM/CADM-ILD患者, 需要立即联合应用GC、CNIs和静脉注射环磷酰胺(IVCY)免疫抑制治疗。对难治性ILD患者可加用利妥昔单抗、托法替尼和血浆交换。抗ARS抗体阳性的ILD患者虽然对GC治疗反应更好, 但更易复发, 因此, 往往需要联合GC和免疫抑制剂(他克莫司、环孢素A、硫唑嘌呤和霉酚酸酯)治疗, 以实现良好的长期控制。最近有一些关于PM/DM/CADM合并ILD(PM/DM/CADM-ILD)治疗的前瞻性...     

中国人群中多发性肌炎的发病率及临床特征

目的分析特发性炎性肌病(IIM)中多发性肌炎(PM)的发生率及其特征, 探讨IIM中PM是否被过度诊断。方法纳入2008—2019年于中日友好医院风湿免疫科住院依据Bohan与Peter标准诊断的所有IIM患者。确定诊断的PM(definite PM, dPM)定义为具有典型的PM临床特征和病理特征, 包括肌酸激酶(CK)升高和肌无力, 肌活检呈现肌细胞膜表达MHC-I阳性和CD8+T细胞浸润肌内膜。同时, 参照IIM各亚型的最新诊断标准, 排除DM、抗合成酶综合征(ASS)、免疫介导的坏死性肌病(IMNM)、散发性包涵体肌炎和其他肌病。应用SPSS 24.0进行统计学分析。Kruskal-Wallis检验和χ2检验用于比较dPM组和其他IIM亚型患者临床特点的差异。结果共1 259例IIM纳入研究, 其中1 015例(80.6%)为DM, 244例(19.4%)为PM。参照严格定义的dPM标准, IIM中仅有0.5%(6/1 259)的患者可被诊断为dPM。原先诊断为PM的患者在新的IIM亚型分类中多数为IMNM和ASS, 其中48.0%(117/244)为IMNM, 32.0%(7...     

特发性炎性肌病合并肺间质病变的生物标志物研究进展

特发性炎性肌病(IIM)是一组以骨骼肌炎症为特征的自身免疫性疾病。肺间质病变(ILD)是IIM最常见的并发症,也是IIM患者死亡的主要原因。IIM-ILD的治疗反应及预后差异大,其治疗取决于ILD的严重与进展程度。因此了解IIM-ILD的危险因素,对于预测ILD的发展、预后及选择治疗方案非常重要。IIM患者可检出多种自身抗体,其中抗合成酶抗体(ASA)、抗黑色素瘤分化相关基因(MDA5)抗体与ILD密切相关,涎液化糖链抗原(KL-6)、铁蛋白、肺表面活性蛋白D(SP-D)、B淋巴细胞刺激因子(BAFF)等生物标志物对预测ILD、监测疾病活动、评估疗效及预后等方面有重要作用。本文对近年来IIM-ILD相关生物标志物的研究进展进行综述。     

特发性炎性肌病的分子病理研究进展

特发性炎性肌病(IIM)是一组临床特点、病理表现和治疗预后各异的自身免疫性疾病。主要临床表现为肌无力,也可影响包括皮肤、关节、肺脏、心脏和消化道等多个骨骼肌外系统和器官,有些IIM的亚型甚至以肌外系统损害为主要表现。近年来发现了多种肌炎特异性抗体与IIM密切相关,不同抗体相关的临床表型、病理改变和对治疗的反应均各不相同,提示存在不同的病理生理机制。目前比较公认基于临床-病理-血清学特点,将IIM进一步分为皮肌炎、抗合成酶抗体综合征、免疫介导坏死性肌病、包涵体肌炎和多发性肌炎这几种亚型。本文介绍了IIM各亚型的分子病理研究的最新进展,以期为临床和病理医生提供参考。     

High Frequencies and co-existing of myositis-specific autoantibodies in patients with idiopathic inflammatory myopathies overlapped to rheumatoid arthritis

A small proportion of patients with rheumatoid arthritis (RA) develop idiopathic inflammatory myopathies (IIM); however, the clinical and immunological characteristics of these patients have not been elucidated. In the present study, we evaluate the frequency of autoantibodies and the accompanying clinical features in patients with IIM overlapped to RA (IIM-RA) and in patients with IIM without RA. Twelve patients with IIM-RA were selected from 142 patients with IIM who were admitted to our hospital. Clinical and laboratory data, including autoantibody test results, were collected from patient medical records. Myositis-specific antibodies (MSAs) were analyzed by immunoprecipitation. Clinically, patients with IIM-RA were more likely to be male, to have polymyositis, and to be older at the time of IIM onset than patients with IIM without RA. Patients with IIM-RA had been treated for 2–25?years prior to the onset of IIM with more than two disease-modifying antirheumatic drugs (DMARDs). Patients with IIM-RA had a high frequency (75.0%) of positivity for MSAs, including anti-Jo-1, anti-PL-7, anti-PL-12, or anti-signal recognition particle (SRP) antibodies; anti-Jo-1 antibody was detected in 4 patients (33.3%). In addition, 2 out of 12 patients with IIM-RA were concurrently positive for two different MSAs, anti-Jo-1, and anti-PL-7 antibodies. In 3 other patients with IIM-RA, anti-Jo-1 antibody, or anti-PL-7 antibody was detected in serum samples collected 6–18?months prior to development of myositis. High frequency and coexistence of MSAs were detected in patients with IIM-RA. MSAs detected in patients with RA even without symptoms of myositis may indicate possible future development of myositis.     

Myositis-specific autoantibodies: overview and recent developments.

Myositis-specific autoantibodies (MSAs) are found in almost half the patients with an idiopathic inflammatory myopathy (IIM). Several clinical and epidemiological studies have suggested that MSAs are associated with specific clinical characteristics. Some of these associations are well-defined and are of clinical significance ( eg, anti-Jo-1 and the anti-synthetase syndrome), others are less well established and can cause unnecessary anxiety for both patients and physicians ( eg, anti-SRP and cardiac involvement). In this review, an overview is given of the various MSAs, their biochemical background, their clinical usefulness, and the promises they hold for a better understanding of IIM.     

Clinical characteristics of interstitial lung diseases positive to different anti-synthetase antibodies

To analyze the clinical, serological, and imaging characteristics of patients with interstitial lung diseases (ILD) positive to different anti-aminoacyl-tRNA synthetase (anti-ARS) antibodies.The clinical data, serological indexes, pulmonary high-resolution computed tomography (HRCT) imaging features and pulmonary functions, and bronchoalveolar lavage fluid of 84 ILD patients with anti-ARS antibody positive in Beijing Chao-yang Hospital, Capital Medical University were reviewed.(1) Anti-ARS antibodies included anti-Jo-1 (42.86%), anti-PL-7 (26.19%), anti-PL-12 (10.71%), anti-EJ (14.29%), and anti-OJ (5.95%). (2) Nonspecific interstitial pneumonia was the main type of patients with ILD positive to antibodies of anti-Jo-1, anti-PL-7, and anti-EJ, organizing pneumonia was the main type of patients with ILD positive to anti-PL-12 antibody and usual interstitial pneumonia was the main type of patients with ILD positive to anti-OJ antibody. (3) Only 14.29% of the patients had typical “triad syndrome” (interstitial pneumonia, myositis, and non-erosive arthritis). Myositis mainly occurred in patients with ILD positive to antibodies of anti-PL-7, anti-Jo-1, and anti-EJ. The incidence of arthritis in ILD patients with anti-Jo-1 was higher than that in ILD patients with anti-PL-12 and anti-EJ (P < .05). The incidence of mechanic''s hand in ILD patients with anti-Jo-1 was higher than that in ILD patients with anti-PL-12 (P < .05).ILD positive to anti-Jo-1 antibody is associated with multiple organ involvement, mainly manifested as myositis, mechanic''s hand, and arthritis. As other clinical manifestations of some ILD patients are relatively hidden, ILD patients should pay attention to the screening of the anti-ARS antibodies and guard against anti-synthetase syndrome.     

Myositis-specific and myositis-associated autoantibodies in Indian patients with inflammatory myositis

We aimed to study the prevalence and clinical associations of myositis-specific autoantibodies (MSAs) and myositis-associated autoantibodies (MAAs) in a large cohort of Indian patients with idiopathic inflammatory myositis (IIM). Clinical details and serum samples were collected from patients with IIM (satisfying Bohan and Peter Criteria, 1975) and CTD-associated myositis. Sera were analysed for antibodies against SRP, Mi2, Jo1, PL7, PL12, EJ, OJ, Ro52, Ku, Pm-Scl 75 and PM-Scl 100, using immunoblot assay. The cohort comprised 124 patients with IIM (M:F = 1:3.6). Fifty-five of them had dermatomyositis (DM), 22 had juvenile dermatomyositis (JDM), 25 had polymyositis (PM) and 22 had connective tissue disease-associated myositis (CTD myositis). Mean disease duration was 10.9 months. ANA was positive in 84 (68.9 %), and MSAs in 61 (49.2 %) patients. Among MSAs, autoantibodies to Mi2, synthetase (Jo1, PL7, PL12, EJ) and SRP were present in 26 (20.9 %), 29 (23.4 %) and 6 (4.8 %) patients, respectively. Prevalence of MAAs was as follows: antibodies to Ro52 in 45 (36.3 %), Ku and PM-Scl 75 in 13 (10.5 %) and PM-Scl 100 in 5 (4 %) patients. Anti-Mi2 antibodies were positively associated with DM (21/55, 38.2 %; p < 0.0001) and pharyngeal weakness (13/34, 38.2 %; p = 0.004) and negatively associated with ILD (0/28; p = 0.001). ILD and mechanics’ hands were significantly more in patients with anti-synthetase antibodies (16/28, 57 % and 14/22, 63.6 %; p < 0.0001). Four of six patients with anti-SRP antibody showed poor response to multiple drugs. Higher prevalence of anti-Mi2 is probably related to higher proportion of patients with DM. Absence of ILD in patients with anti-Mi2 antibody suggests that it may protect against ILD. In Indian population also, anti-synthetase antibodies are associated with ILD, and anti-SRP antibodies with poor response to treatment.     

Unusually high frequency of autoantibodies to PL-7 associated with milder muscle disease in Japanese patients with polymyositis/dermatomyositis

OBJECTIVE: Autoantibodies to aminoacyl transfer RNA synthetases, such as histidyl (Jo-1), threonyl (PL-7), alanyl (PL-12), glycyl (EJ), and isoleucyl (OJ), are closely associated with a subset of patients with polymyositis/dermatomyositis (PM/DM) complicated by interstitial lung disease (ILD). Anti-Jo-1 is by far the most common, found in 15-25% of patients with PM/DM, whereas the other types are found in only approximately 3% of these patients. In this study, the clinical associations of these autoantibodies in Japanese patients with PM/DM were investigated. METHODS: The diagnoses of PM/DM and amyopathic DM (ADM) were based on the Bohan and Peter criteria and Sontheimer's definition, respectively. Sera from 36 Japanese patients with PM/DM (13 with PM, 20 with DM, 3 with ADM) were screened by immunoprecipitation and by enzyme-linked immunosorbent assay (for Jo-1). Clinical and laboratory data were collected. RESULTS: The frequencies of autoantibodies to Jo-1 (22%) and to EJ, OJ, and PL-12 (3-6%) were similar to those found in previous studies, including studies of Japanese subjects. However, anti-PL-7 was found in 17% of patients, in contrast to a frequency of 1-4% in previous studies (P < 0.02-0.0002). The 6 anti-PL-7-positive patients were not related, and no skewing in year or month of disease development, place of residence or work, or occupation was found. All patients had ILD, consistent with the clinical features of antisynthetase-positive patients. The patients with anti-PL-7 had lower serum muscle enzyme levels and milder muscle weakness (P < 0.05) compared with anti-Jo-1-positive patients. CONCLUSION: Anti-PL-7 was found at an unusually high frequency in this group of Japanese patients with myositis. Although anti-PL-7, similar to anti-Jo-1, is associated with PM/DM with ILD, muscle involvement in the patients with anti-PL-7 appeared to be milder than that in the anti-Jo-1 subset.     

HLA-D region genes associated with autoantibody responses to histidyl-transfer RNA synthetase (Jo-1) and other translation-related factors in myositis

Myositis has been associated with HLA-B8 and DR3, especially in white patients with polymyositis and serum anti-Jo-1 antibodies. Twenty-eight patients with myositis and serum translation-related autoantibodies anti-Jo-1, anti-PL-7, anti-PL-12, anti-KJ, and anti-SRP were studied for HLA class II specificities by Southern blotting with HLA-DR beta, DQ beta, and DQ alpha probes. The association of HLA-DR3 (DRw17) with anti-Jo-1 antibodies in white myositis patients was confirmed (P = 0.003, relative risk 8.9). However, HLA-DRw52 haplotypes, regardless of subtype, were present in all of the white and black patients with serum anti-Jo-1 and other translation-related autoantibodies. Moreover, one anti-Jo-1 positive patient had HLA-DRw8, an HLA-DRw52 haplotype on which the DR beta 3 gene has been partially deleted. No HLA-DQ specificity or allele was common to all patients. The HLA-DR3, DR5, DRw6, and DRw8 haplotypes, which bear the HLA-DRw52 specificity, share the most homology in the DR beta 1 first hypervariable region at amino acid positions 9-13. Thus, this DR beta 1 region appears to be the most likely candidate "epitope" for translation-related autoimmune responses in inflammatory myositis.     

Treatment of antisynthetase-associated interstitial lung disease with tacrolimus

OBJECTIVE: To assess the efficacy of tacrolimus in patients with anti-aminoacyl-transfer RNA synthetase (anti-aaRS)-associated interstitial lung disease (ILD) and idiopathic inflammatory myopathy (IIM). METHODS: Ninety-eight patients with anti-aaRS autoantibodies were identified in our IIM cohort of 536 patients. The medical records of 15 patients with anti-aaRS-associated ILD treated with tacrolimus between 1992 and 2003 were retrospectively reviewed. Pulmonary parameters of response included forced vital capacity, forced expiratory volume in 1 second, and diffusing capacity for carbon monoxide. Manual muscle testing results, serum creatine kinase (CK) levels, and the daily corticosteroid dosage were used to assess improvement in myositis. Random coefficient modeling considering polynomials of time was used to assess the clinical response to tacrolimus. RESULTS: All patients, except for 1, who had pure ILD, had definite or probable IIM. Two patients received tacrolimus for fewer than 3 months, and their data were not analyzed. For the remaining 13 patients, the mean age at onset of ILD was 46.9 years, and the mean duration of pulmonary disease was 14.7 months. Twelve patients had anti-histidyl-transfer RNA synthetase autoantibody (anti-Jo-1) and 1 had anti-alanyl-transfer RNA synthetase autoantibody (anti-PL-12). Patients received tacrolimus for an average of 51.2 months. A significant improvement was observed in all pulmonary parameters measured. The serum CK level declined significantly, and 10 patients had either an improvement in muscle strength or maintained normal muscle strength. A statistically significant reduction in the corticosteroid dosage was also observed. CONCLUSION: Tacrolimus is a well-tolerated and effective therapy for managing refractory ILD and myositis in anti-aaRS-positive patients.     

Myositis-specific and myositis-associated autoantibodies in a large Indian cohort of inflammatory myositis

BackgroundThe Idiopathic Inflammatory Myositis (IIM) are heterogenous with distinct clinical phenotypes associated with specific myositis specific antibodies (MSA) and myositis associated antibodies (MAA).ObjectivesTo evaluate the frequency, pattern and associations of MSA/MAA in a large Indian cohort of IIM.MethodsAdult and juvenile IIM (2017 ACR/EULAR criteria), were recruited in the MyoCite cohort between 2017and 2020 at a tertiary center in Northern India. Standardized clinical and laboratory variables were extracted from the database archive. Serum samples were evaluated for the presence of MSAs/MAAs by Line immunoassay and anti-nuclear antibodies (ANA) by Immunofluorescence assay (IFA). The prevalence and clinical associations of different MSA/MAAs were assessed.ResultsMSA and MAAs were tested in 250 IIM patients (214 adults, 36 children) of age [40 (30^–49), 13 (7.5–16) years] and disease duration [ 7 (3–17), 6 (2–17) months] comprising predominantly of Dermatomyositis (DM) followed by Overlap myositis (OM). MSAs/MAAs were found in 148 (59.2%, 60.7% adults and 50% JIIM), of which two-thirds were MSA (95, 64% overall). Two cases (0.8%) had more than one MSA. In adult IIM, the most common MSA was anti-Jo-1 (10%), whereas it was anti-MDA5 and anti-NXP2 4 (11%) each in Juvenile IIM (JIIM). 76.0% (172/226) were ANA positive, with speckled pattern being the most common (37%,). Nearly two-thirds (54, 61%) of those with negative ANA had MSA/ MAA. Nearly half (18/54, 54.6%) had MSA associated with cytoplasmic patterns. ARS (anti-aminoacyl-tRNA synthetase) were associated with mechanic's hands (OR-7.06), ILD (OR-4.4), and arthritis (OR-2.23). Clinical associations of anti-Jo-1 and non-Jo-1 Anti synthetase syndrome (ASS) did not differ. Anti-MDA-5 associated with oral ulcers (OR-8.3), fever (OR-8.6) and weight loss (OR-7.35) in adults, and arthritis (OR-11.5), and periungual rash (OR-9.6) in children. Anti-TIF-1γ associated with photosensitivity (OR-10.44) and malignancy (OR-34) in adults, and cuticular overgrowth (OR-11.2) in children.ConclusionMyositis autoantibodies are seen in two-thirds IIMs and are associated with distinct clinical subsets. Jo-1 and non-Jo-1 ASS exhibit similar characteristics. The association of anti-TIF1 γ with malignancy was confirmed in adults. MSA/MAA were present in two-thirds of those with negative ANA and MSA were nearly always mutually exclusive.     

Autoantibody profiles in the sera of European patients with myositis

OBJECTIVE: To determine the prevalence of myositis specific autoantibodies (MSAs) and several myositis associated autoantibodies (MAAs) in a large group of patients with myositis. METHODS: A total of 417 patients with myositis from 11 European countries (198 patients with polymyositis (PM), 181 with dermatomyositis (DM), and 38 with inclusion body myositis (IBM)) were serologically analysed by immunoblot, enzyme linked immunosorbent assay (ELISA) and/or immunoprecipitation. RESULTS: Autoantibodies were found in 232 sera (56%), including 157 samples (38%) which contained MSAs. The most commonly detected MSA was anti-Jo-1 (18%). Other anti-synthetase, anti-Mi-2, and anti-SRP autoantibodies were found in 3%, 14%, and 5% of the sera, respectively. A relatively high number of anti-Mi-2 positive PM sera were found (9% of PM sera). The most commonly detected MAA was anti-Ro52 (25%). Anti-PM/Scl-100, anti-PM/Scl-75, anti-Mas, anti-Ro60, anti-La, and anti-U1 snRNP autoantibodies were present in 6%, 3%, 2%, 4%, 5%, and 6% of the sera, respectively. Remarkable associations were noticed between anti-Ro52 and anti-Jo-1 autoantibodies and, in a few sera, also between anti-Jo-1 and anti-SRP or anti-Mi-2 autoantibodies. CONCLUSIONS: The incidence of most of the tested autoantibody activities in this large group of European patients is in agreement with similar studies of Japanese and American patients. The relatively high number of PM sera with anti-Mi-2 reactivity may be explained by the use of multiple recombinant fragments spanning the complete antigen. Furthermore, our data show that some sera may contain more than one type of MSA and confirm the strong association of anti-Ro52 with anti-Jo-1 reactivity.