POS0870\u2005CLINICAL CHARACTERIZATION OF PORTUGUESE PATIENTS WITH ANTISYNTHETASE SYNDROME

Abstract

Antisynthetase syndrome (ASyS) may have different clinical phenotypes and outcomes associated with different anti-aminoacyl RNA-synthetase (anti-ARS) antibodies. Its wide clinical spectrum can include inflammatory myopathy, interstitial lung disease (ILD), arthritis, fever, mechanic’s hands, and Raynaud phenomenon (RP).To describe a nationwide, multicentre cohort of Portuguese patients with ASyS.Retrospective analysis of patients with ASyS from nine Portuguese Rheumatology centers. Data on patients’ signs and symptoms, laboratory results, pulmonary radiological findings (computed tomography) and treatment (immunomodulators) were collected.Among the 70 patients included, 42 patients (60%) were anti-Jo1–positive, 11 (15.7%) were anti-PL12–positive, 10 (14.3%) were anti-PL7–positive, 4 (5.7%) were anti-EJ–positive and 2 (2.9%) were anti-OJ positive. In one patient it was not possible to identify the type of antibody. Antibody overlap was found in 15 patients (21.4%), who were positive for anti-Ro52 antibodies. The general clinical characteristics are shown in Table 1. The diagnostic delay was greater in patients positive for anti-OJ, followed by anti-Jo-1 and anti-PL12. The follow-up was shorter for anti-PL7 and anti-OJ-positive patients. Anti-PL7-positive patients had lower rates of arthritis when compared to anti-Jo1 (p< 0.01). When compared with anti-Jo-1 ARS, myositis was less common in anti-PL12 (p < 0.01). ILD prevalence was similar in the different ARS subgroups. Glucocorticoids (GCs) were the most frequently used class of drugs. A more conservative treatment plan (e.g. GCs plus methotrexate or azathioprine) was the treatment of choice in ASyS with myositis and/or arthritis involvement. Rituximab or mycophenolate mofetil were preferred when lung involvement occurred. Only two deaths were reported, being one associated with lung neoplasia.This is the first study investigating the clinical phenotypes of Portuguese patients with ASyS. These results are generally concordant with data retrieved from international cohorts.[1]Mahler M, Miller FW, Fritzler MJ. Idiopathic inflammatory myopathies and the anti-synthetase syndrome: a comprehensive review. Autoimmun Rev 2014;13:367–71.Table 1.Patient characteristics according to the anti-ARS. ILD - interstitial lung disease; IQR- interquartile range; NSIP - Non-specific interstitial pneumonia; UIP - Usual interstitial pneumonia; yrs - yearsVariablesOverall, n=70Jo-1, n=42(60%)PL-12, n=11 (15.7%)PL-7, n=10 (14.3%)EJ, n=4 (5.7%)OJ, n=2 (2.9%)Mean age at onset, yrs52 ± 1546.6 ± 14.455.2 ± 14.756.5±12.556.3±11.273.5±2.1Female, n (%)49 (70)29 (69)9 (81.8)7 (70)2 (50)2 (100)Median age in years at disease onset (IQR)52 (15-75)48 (15-70)59 (20-70)62 (39-73)60 (40-65)73.5 (72-75)Median follow-up time in yrs (IQR)3 (0-32)5 (0-32)3 (0-13)1 (1-4)4 (2-21)1 (0-2)Median diagnostic delay in yrs (IQR)6 (1-33)7 (1-33)7 (2-19)4 (1-23)1.5 (1-2)12.5 (2-21)Myositis, n (%) and Comparison Anti-Jo.1 ARS vs PL-12 and PL-736 (51.4)25 (59.5)3 (27.3)*p < 0.014 (40)p=0.73 (75)-0-ILD, n (%) and Comparison Anti-Jo.1 ARS vs PL-12 and PL-753 (75.7)33 (78.6)8 (72.7)p = 0.986 (60) p=0.564 (100)-1 (50)- ILD pattern - NSIP, n (%)30 (56.6)18 (54.5)6 (75)3 (50)1 (25)0 ILD pattern - UIP, n (%)6 (11.3)3 (9.1)1 (12.5)1 (16.7)1 (25)0 ILD pattern - other specific pattern, n (%)6 (11.3)4 (12.1)02 (33.3)1 (25)0 ILD pattern - non-specific pattern, n (%)11 (15.7)8 (24.2)1 (12.5)01 (25)1 (100)Mechanic’s hands (%), n (%)23 (32.9)14 (33.3)3 (27.3)2 (20)01 (50)General impairment, n (%)18 (25.7)11 (26.2)3 (27.3)2 (20)2 (50)0Fever, n (%)7 (10)4 (9.5)2 (20.2)01 (25)0Raynaud phenomenon, n (%)22 (31.4)11 (26.2)7 (63.6)02 (50)0Arthritis, n (%) and Comparison Anti-Jo.1 ARS vs PL-12 and PL-743 (61.4)29 (69)5 (45.4)p=0.072 (20)*p < 0.012 (50)-1 (50)-Malignancy, n (%)4 (5.7)3 (7.1)1 (9.1)000Deaths, n (%)2 (2.9)2 (2.4)0001 (50)None declared