AB0614 METHOTREXATE DOESN’T LOWER THE RISK OF DEVELOPING INTERSTITIAL LUNG DISEASE IN PATIENTS WITH IDIOPATHIC INFLAMMATORY MYOPATHIES WITH JO-1 ANTIBODIES.
Background:In patients with idiopathic inflammatory myopathies (IIM) most commonly found autoantibody against histidyl-tRNA synthetase (anti-Jo-1) is associated with development of interstitial lung disease (ILD), which has been recognized as a serious mortality factor.Objectives:To assess if methotrexate as an initial steroid sparing agent lowers the risk of developing ILD in anti-Jo-1 positive patients diagnosed with IIM.Methods:Medical records of IIM patients treated in a referral clinic in capital city of Poland between 2008 and 2018 were reviewed. Inclusion criteria were: fulfillment of ACR/EULAR 2017 classification criteria for IIM, positivity of anti-Jo-1 antibodies in the EUROLINE test, introduction of corticosteroids equivalent to ≥0,5mg of prednisone. Exclusion criteria: insufficient data on disease course, history of IIM <18 months.Results:29 patients were included for this analysis. ILD was present at the onset in 52% (n:15) patients. Other 14 patients were treated initially with corticosteroids ≥0,5mg/kg along with methotrexate up to 25mg/week. In all 14 patients methotrexate was well tolerated and led to successful reduction of steroid dose. However, ILD attributed to the primary disease appeared in follow up in 50%(n:7) of these patients (medium 36 months), which resulted in alteration of treatment. In 7 patients ILD didn’t develop.Conclusion:Our study shows that methotrexate in dose up to 25mg/week doesn’t lower the risk of developing ILD in Jo-1 positive IIM patients in the long term suggesting that other medication should be used as a first line treatment for this group.References:[1]Factors affecting survivorship in polymyositis: a life-table study of 124 patients. Medsger TA, Robinson H, Masi AT. Arthritis Rheum 1971;14:249–58[2](2018). Treatment of adult idiopathic inflammatory myopathies with conventional immunosuppressive drugs. Keyßer, G., Zierz, S., & Kornhuber, M. Z Rheumatol. 2019;78(2):183–189.[3]2017 European League Against Rheumatism/American College of Rheumatology classification criteria for adult and juvenile idiopathic inflammatory myopathies and their major subgroups Lundberg IE, Tjärnlund A, Bottai M, et al. Ann Rheum Dis. 2017;76(12):1955–1964.Disclosure of Interests:None declared