Clinical features of anti-synthetase syndrome associated interstitial lung disease: a retrospective cohort in China

Abstract

Background Anti-synthetase syndrome (ASSD) is a chronic autoimmune condition characterized by antibodies directed against an aminoacycl transfer RNA synthetase (ARS) along with a group of clinical features including the classical clinical triad: inflammatory myopathy, arthritis, and interstitial lung disease (ILD). ASSD is highly heterogenous due to different organ involvement, and ILD is the main cause of mortality and function loss, which presents as different patterns when diagnosed. We designed this retrospective cohort to describe the clinical features and disease behaviour of ASSD associated ILD. Methods Data of 108 cases of ASSD associated ILD were retrospectively collected in Beijing Chaoyang Hospital from December 2017 to March 2019. Data were obtained from the Electronic Medical Record system. Patients were divided into 5 groups according to distinct aminoacyl tRNA synthetase (ARS) antibodies. Results Overall, 108 consecutive patients were recruited. 33 were JO-1 positive, 30 were PL-7 positive, 23 were EJ positive, 13 were PL-12 positive and 9 were OJ positive. The JO-1 (+) group had a significant higher rate of mechanic’s hand (57.6%) than other 4 groups. Polymyositis/dermatomyositis (PM/DM) was diagnosed in 25 (23.1%) patients and no difference was observed among the 5 groups. The PL-7 (+) group had a higher frequency of UIP pattern (13.3%) than the other 4 groups but the difference was not significant, and the EJ (+) group had the most frequent OP pattern (78.2%), which was significantly higher than the PL-7 (+) (P < 0.001) and PL-12 (+) groups (P = 0.025). The median follow-up time was 10.7 months, during which no patients died. All received prednisone treatment, with or without immunosuppressants. At the 6-month follow-up, 96.3% of all patients (104/108) had a positive response to therapy, the JO-1 (+) and EJ (+) groups had a significantly higher improvement of forced vital capacity than the other 3 groups (P < 0.05), and the PL-7 group had the lowest FVC improvement (P < 0.05). The JO-1 (+) group and EJ (+) group had significantly higher anti-Ro-52 positive occurrence than the other 3 groups (P < 0.05). Conclusion Anti PL-7 antibody had the same frequency as anti-JO-1 in ASSD-ILD, in which the ILD pattern was different with distinct anti-ARS antibodies. Most ASSD-ILD had a positive response to steroid therapies, with or without immunosuppressants. The PL-7 (+) group had the highest occurrence of UIP pattern, and a significantly lower response to therapy.

Nephrotic Syndrome as an Extramuscular Manifestation of Anti-EJ Antibody-Positive Dermatomyositis: A Case Report and Review of the Literature

“…The patient was subsequently found to have anti-EJ Ab using BlueDiver immunoblot kits (D-tek, Belgium) that measured each anti-ARS Ab separately. The frequency of anti-EJ Ab in ASS varies among previous studies, ranging from 1.8% to 23% [ 4 , 51 – 53 ]. Thus, Pinal-Fernandez et al investigated the frequency of anti-ARS Abs based on the Johns Hopkins Myositis Center cohort and demonstrated that anti-Jo1 Ab was most prevalent (73.4%) in ASS, followed by anti-PL12 (13.6%), anti-PL7 (9.5%), anti-EJ (1.8%), and anti-OJ (1.8%) Abs [ 51 ].…”

“…Furthermore, Hamaguchi et al reported that anti-EJ Ab was detected in 38 out of 166 Japanese patients with ASS (23%) [ 4 ]. As for its frequency in China, Zhan et al demonstrated that anti-EJ Ab was the third most prevalent anti-ARS Ab, preceded by anti-Jo-1 and anti-PL7 Abs in patients with ASS complicated by ILD with its frequency of 21% (23 out of 108 patients) [ 53 ].…”

A multidisciplinary approach to the diagnosis of antisynthetase syndrome

“…In a large Chinese cohort, the spectrum varied from an OP pattern predominantly seen in anti-Jo1 positive ASyS with an NSIP pattern evident in anti-PL12 and anti-PL7. In anti-EJ patients, an OP pattern was most predominantly seen ( 35 ). Other smaller cohorts have shown overlap NSIP/OP patterns to be more prevalent in anti-Jo1 and anti-PL12 ( 36 ).…”

A Comparison of Line Blots, Enzyme-linked Immunosorbent, and RNA-immunoprecipitation Assays of Antisynthetase Antibodies in Serum Samples from 44 Patients

“…These include anti-Jo-1 (targeting histidyl tRNA synthetase), anti-PL7 (threonyl), anti-PL12 (alanyl), anti-OJ (isoleucyl), anti-KS (asparaginyl), anti-EJ (glycyl), anti-Zo (phenylalanyl), and anti-Ha (tyrosyl) antibodies (2)(3)(4). A single patient rarely produces multiple overlapping antibodies, so the antibodies in each patient result in the manifestation of unique clinical symptoms, progression, and a prognosis (5)(6)(7)(8)(9)(10).…”