Clinical characteristics of Vietnamese patients with idiopathic inflammatory myopathies and autoantibodies to aminoacyl-transfer RNA synthetases.

To assess clinical phenotypes of anti-aminoacyl-transfer RNA synthetases (aaRS) autoantibodies in Vietnamese patients of Kinh ethnicity with idiopathic inflammatory myopathies (IIM). In a cross-sectional study 23 patients with anti-aaRS autoantibodies were compared to 36 patients with other myositis-specific antibodies and to 69 seronegative patients with IIM. Assessments included muscle performance, extra-muscular involvement, and disease activity according to the International Myositis Assessment and Clinical Studies (IMACS). Sera were tested by a line immunoassay (Euroline Myositis Profile 4). The frequency of anti-Jo-1 antibodies was 56.5%, anti-EJ antibodies 26.1%, and anti-PL-7 antibodies 17.4%, while anti-PL-12 and anti-OJ antibodies were not present in any case. All patients with anti-aaRS autoantibodies had signs of myositis. At time of investigation 22/23 patients had muscle weakness, 52.2% arthritis, 34.8% Raynaud's phenomenon, 73.9% fever, 14.3% mechanic's hands and 56.5% dysphagia. Interstitial lung disease was present in 52.2%, and pulmonary hypertension in 56.5%. The anti-aaRS autoantibody positive group had higher disease activity in the domains of skin and pulmonary disease compared to the seronegative group and had lower disease activity in skeletal disease compared to the anti-melanoma differentiation-associated protein 5-positive patients. The clinical presentation of antisynthetase syndrome was similar between the aaRS autoantibody specificities with the exception of more frequent pulmonary hypertension in anti-Jo-1 positive patients. Different aaRS autoantibody specificities may vary between different ethnic populations for reasons that still need to be clarified. Furthermore, the high frequency of pulmonary hypertension is noteworthy but otherwise clinical manifestations associated with aaRS autoantibodies did not differ from other ethnic populations.

Phuong TNT ，Ngoc LNT ，Rönnelid J ，Padyukov L ，Lundberg IE ... -  《-》

Autoantigenic properties of the aminoacyl tRNA synthetase family in idiopathic inflammatory myopathies.

Preger C ，Notarnicola A ，Hellström C ，Wigren E ，Fernandes-Cerqueira C ，Kvarnström M ，Wahren-Herlenius M ，Idborg H ，Lundberg IE ，Persson H ，Gräslund S ，Jakobsson PJ ... -  《-》

Idiopathic inflammatory myopathies and the anti-synthetase syndrome: a comprehensive review.

Autoantibodies are a hallmark in the diagnosis of many systemic autoimmune rheumatic diseases (SARD) including idiopathic inflammatory myopathies (IIM). Based on their specificity, autoantibodies in IIM are grouped into myositis specific (MSA) and myositis associated autoantibodies (MAA). Among the MSA, autoantibodies against aminoacyl-tRNA synthetases (ARS) represent the most common antibodies and can be detected in 25-35% of patients. The presence of ARS and other autoantibodies has become a key feature for classification and diagnosis of IIM and is increasingly used to define clinically distinguishable IIM subsets. For example, anti-ARS autoantibodies are the key features of what has become known as anti-synthetase syndrome (aSS), characterized by multiple organ involvement, primarily interstitial lung disease, often accompanied by myositis, non-erosive arthritis, Raynaud's phenomenon, fever, and "mechanic's hands". Autoantibodies directed to eight different ARS have been described: Jo-1 (histidyl), PL-7 (threonyl), PL-12 (alanyl), OJ (isoleucyl), EJ (glycyl), KS (asparaginyl), Zo (phenylalanyl) and Ha (tyrosyl). Each anti-ARS antibody seems to define a distinctive clinical phenotype. Although several research methods and commercial tests are available, routine testing for anti-ARS autoantibodies (other than anti-Jo-1/histidyl-tRNA synthetase) is not widely available, sometimes leading to delays in diagnosis and poor disease outcomes.

Mahler M ，Miller FW ，Fritzler MJ 《-》

Clinical manifestations of skin, lung and muscle diseases in dermatomyositis positive for anti-aminoacyl tRNA synthetase antibodies.

Patients with dermatomyositis positive for anti-aminoacyl tRNA synthetase (ARS) antibodies, also known as antisynthetase syndrome (ASS), frequently present with mechanic's hand and interstitial lung disease (ILD). We first screened the antibody profiles of 59 patients with dermatomyositis, and then examined the cutaneous, muscular and pulmonary manifestations characteristic for patients with ASS. The anti-ARS antibodies Jo-1, PL-7, PL-12, EJ and KS, along with antibodies to TIF1-γ, MDA5 and Mi-2, were examined. Among the 59 patients, 20, 21, 15 and three patients were classified into the ASS, non-ASS, myositis-specific antibody-negative and unknown groups, respectively. Five of 16 patients (31%) with ASS had six relatives with a history of collagen diseases, within the second degree of relationship, including two cases of dermatomyositis (vs the non-ASS group, P = 0.018). Patients with ASS more frequently presented with fever and arthralgia, and had elevated levels of C-reactive protein. Nine of the 11 finger lesions (82%) clinically diagnosed as mechanic's hands showed a psoriasiform tissue reaction. ILD was observed in 19 of 20 patients (95%) with ASS, and eight of 21 patients (38%) in the non-ASS group, in which six patients possessed anti-MDA5 antibody. Patients with ASS showed higher serum levels of muscle enzymes, and four of 12 patients (33%) had fasciitis-dominant myopathy, while only one of 11 patients (9%) in the non-ASS group had fasciitis-dominant myopathy. Patients with ASS often present with a psoriasiform tissue reaction in the hand lesions and fasciitis-dominant myopathy, and the relatives of those with ASS are at high risk for collagen diseases.

Fukamatsu H ，Hirai Y ，Miyake T ，Kaji T ，Morizane S ，Yokoyama E ，Hamada T ，Oono T ，Koyama Y ，Norikane S ，Iwatsuki K ... -  《-》

[Idiopathic Inflammatory Myopathy and Anti-aminoacyl-tRNA Synthetase Antibody].

Maeda MH 《-》