AB0604 EVALUATION OF PATIENTS WITH ANTISYNTHETASE SYNDROME AND INTERSTITIAL LUNG DISEASE BASED ON THE RADIOLOGICAL PATTERN
Authors: A. Ruiz Roman, J. A. Rodriguez Portal
Journal: Annals of the Rheumatic Diseases (2020)

Background: Antisynthetase syndrome is an autoimmune rheumatologic disease characterized by the presence of specific antibodies that are known as antisynthetase antibodies and with a varied clinic, including arthritis, myositis or interstitial lung disease (ILD), among others. ILD is the manifestation that associates the highest morbi / mortality and can occur with different characteristic radiological patterns: usual interstitial pneumonia (UIP), non-specific interstitial pneumonia (NSIP), organized pneumonia (OP) Objectives: Describe the clinical, serological and prognostic characteristics of patients with antisynthetase syndrome with interstitial pulmonary involvement (ILD) based on their radiological pattern. Methods: Retrospective descriptive study of patients with a clinical diagnosis of antisynthetase syndrome in which they show positive for some antisynthetase antibody and with clinical follow-up of at least 6 months in a reference center consultation between the period from January 2008 to September 2019. In those patients who presented interstitial lung involvement clinical, analytical and prognostic variables were evaluated (including spirometry) based on the radiological pattern presented by high-resolution computed tomography (HRCT) of the chest Results: 32 patients (24 women and 8 men) were included in the study. 7 cases (21.9%) did not present pulmonary involvement, while the remaining 25 cases (78.1%) presented with interstitial lung involvement. Of the patients diagnosed with ILD, 4 cases (12.5%) had an interstitial pattern UIP, 17 cases (53.1%) had an interstitial pattern of NSIP and another 4 (12.5%) interstitial pattern of OP. From an analytical point of view, the most frequent antisynthetase antibody in our sample was antiJo1 with 29 cases (96.9%) and less frequently the antiPL12 antibody with 2 cases and antiPL7 with 1 case. The specific characteristics depending on the type of EPID pattern are summarized in Table 1. Table 1. CHARACTERISTICS ILD PATTERN Pattern UIP N=4 Pattern NSIP N=17 Pattern OP N=4 Gender (Female) n (% ) 4 (100) 11 (64.7) 3 (75.0) Age at diagnosis 47.5 ± 12.9 52.9 ± 10.5 42.0 ± 12.9 Myositis, n(% ) 2 (50.0) 13 (76.5) 4 (100) Arthritis, n (% ) 3 (75.0) 15 (88.2) 3 (75.0) Fever, n (% ) 1 (25.0) 9 (52.9) 2 (50.0) Mechanic´s hands, n(% ) 2 (50.0) 7 (41.2) 2 (50.0) Raynaud´s phenomen, n (% ) 1 (25.0) 8 (47.1) 1 (25.0) Skin involvement, n(% ) 2 (50.0) 10 (58.8) 4 (100) Treatment, n(% ) Glucocorticoids 4 (100) 16 (94.1) 4 (100) Immunosuppresants 4 (100) 16 (94.1) 4 (100) Biological therapy 1 (25.0) 8 (47.1) 2 (50.0) Drug´s number (mean, SD ) 3 ± 0.8 5 ± 2.9 4.7 ± 1.8 Antisynthetase antibodies, n(% ) Anti Jo1 3 (75.0) 15 (88.2) 4(100) PL7 0 (0) 1 (5.9) 0 (0) PL12 1 (25.0) 1 (5.9) 0 (0) Ro52 3 (75.0) 14 (82.4) 2 (50.0) RF positive 1 (25.0) 4 (23.5) 1 (25.0) CK increase 2 (50.0) 11 (64.7) 4 (100) Aldolase increase 2 (50.0) 12 (70.6) 4 (100) Functional respiratory tests: mean(CI95% ) Variation DLCOc(% ) -4.4 (-12.5, 3.7) -2.5(-6.1, 1.0) 7.4 (-10.6, 25.3) Variation FVC(% ) -1.1 (-12.8, 9.1) 6.0 (3.2, 8.8) 7.5 (-9.5, 24.6) Variation FEV1(% ) 0 (0-2.25) 5.0 (1.9, 8.3) 7.35 (-18.0, 32.7) Variation FEV1/FVC(% ) 0.5 (-7.1, 8.2) -1.3 (-2.22, -0.37) -0.4(-12.88, 11.98) Conclusion: ILD is a frequent and serious manifestation that can occur in patients with antisynthetase syndrome, which may have different radiological patterns. In our series, the most observed radiological pattern has been the NSIP pattern with 68%. The pattern most associated with the Ro 52 antibody was the UIP pattern and the NSIP pattern. As for the group that required the largest numbers of drugs (including biological therapy) it was the NSIP pattern. When evaluating changes in respiratory function tests, the pattern that shows a tendency to improve over time is organized pneumonia with improvement of the DLCO, FVC, FEV1, FEV1 / FVC, while the UIP pattern showed a worsening of the DLCO and the FVC. Disclosure of Interests: None declared