Myositis-associated antibodies predict the severity of lung involvement in adult patients with inflammatory myositis - a cohort study of 70 adult patients with myositis in a single center

Josefin Marklund; Balsam Hanna; Tao Jin; Rille Pullerits

doi:10.3389/fmed.2024.1340310

Myositis-associated antibodies predict the severity of lung involvement in adult patients with inflammatory myositis - a cohort study of 70 adult patients with myositis in a single center

Front Med (Lausanne). 2024 Mar 28:11:1340310. doi: 10.3389/fmed.2024.1340310. eCollection 2024.

Authors

Josefin Marklund¹, Balsam Hanna¹, Tao Jin^{1

2}, Rille Pullerits^{1

2

3}

Affiliations

¹ Department of Rheumatology, Sahlgrenska University Hospital, Gothenburg, Sweden.
² Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
³ Department of Clinical Immunology and Transfusion Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden.

Abstract

Introduction: Idiopathic inflammatory myopathies (IIMs) encompass a diverse group of diseases characterized by considerable variability in clinical manifestations, antibody profiles, and responsiveness to immunosuppressive therapies. This study aimed to investigate the association between organ involvement and distinct myositis autoantibodies in individuals with IIM in a single-center cohort.

Methods: Patients with ICD diagnoses M33.1, M33.2, M33.9, or M609 who (1) had been tested with Euroline blot assay for myositis autoantibodies and (2) met the classification criteria of definite/probable polymyositis (PM) or dermatomyositis (DM), anti-synthetase syndrome (ASS), or inclusion body myositis (IBM) were included. Medical journals were retrospectively examined with respect to clinical disease features.

Results: Seventy patients (median age 58 years; 66% females) were included and represented the following diagnosis: PM (n = 23), DM (n = 21), ASS (n = 23), and IBM (n = 3). Most of the patients (87%) presented a muscle biopsy indicative of myositis. The presence of autoantibodies was as follows: myositis-specific antibodies, MSA (n = 53), myositis-associated antibodies, MAA (n = 33), both MSA + MAA (n = 24), MSA only (n = 29), MAA only (n = 9), no MSA, or MAA (n = 8). Anti-Jo-1 was the most common MSA (19%), whereas the most common MAA was anti-Ro/SSA52 (31%). We observed a significant association between antibody patterns and lung disease. In our cohort, 47% of the patients in the whole study group, 86% of patients with anti-SSA52, and 100% with anti-Jo-1 had pulmonary involvement. Patients with both MSA and MAA had a higher incidence of lung disease and decreased CO-diffusion capacity. This was especially prominent in anti-Ro/SSA52-positive patients. Interestingly, none of the patients suffered from lung disease if only antibodies against Mi-2α, Mi-2β, NXP2, HMGCR, and TIF1γ were present or no MSA/MAA were detected.

Discussion: The simultaneous presence of both MAA and MSA indicates an increased risk of lung involvement in patients with inflammatory myopathies. The presence of any MAA, and especially anti-Ro/SSA52, is associated with more severe pulmonary disease. Our data suggest that MAA antibodies might be relevant markers for early detection and treatment of lung involvement in IIM.

Keywords: anti-Ro/SSA52; idiopathic inflammatory myopathy; lung involvement; myositis-associated antibody; myositis-specific antibody.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This study was supported by the Swedish Association against Rheumatism (R-981470 to TJ, R-862061, R-969562 to RP), the Regional agreement on medical training and clinical research between the Western Götaland county council and the University of Gothenburg (ALFGBG-926621, ALFGBG-965012 to RP), the regional research foundation of Västra Götalandsregionen (VGFOUREG-846071, VGFOUREG-930646, VGFOUREG −940162 to TJ), and the Gothenburg Medical Society (GLS-889421 to RP, GLS-935009 to BH). The funders had no role in study design, data collection and analysis, the decision to publish, or the preparation of the manuscript.