AB1059 LUPUS ERYTHEMATOSUS-LIKE SYNDROME INDUCED BY ANTI-TNF THERAPY IN RHEUMATIC DISEASES AND INFLAMMATORY BOWEL DISEASE: DESCRIPTION OF A MONOCENTRIC FOLLOW-UP COHORT
Authors: C. Gomes, M. Diz Lopes, B. M. Fernandes, A. Martins, D. Santos Oliveira, F. Magro, M. Bernardes, L. Costa
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Anti-tumor necrosis factor-α (anti-TNF) therapy is often part of the treatment strategy for rheumatic diseases (RD) and inflammatory bowel disease (IBD). An association between anti-TNF agents and the development of lupus erythematosus (LE)-like syndrome has been established and some patients may have a definitive diagnosis of systemic lupus erythematosus (SLE), requiring appropriate treatment. To date, no studies have been conducted to analyze follow-up between rheumatic and IBD patients who have developed LE-like syndrome induced by anti-TNF agents. <h3>Objectives:</h3> To assess clinical and serological markers of LE-like syndrome induced by anti-TNF therapy, and to characterize its development, in patients with RD and IBD receiving treatment with anti-TNF. <h3>Methods:</h3> In this monocentric descriptive study, with a minimum 6-month follow-up and conducted at a tertiary university hospital (Rheumatology Department), we reviewed the clinical and serological parameters of 8 patients with RD and 11 patients with IBD, all diagnosed with LE-like syndrome induced by anti-TNF therapy. Statistical analysis, using student's t test, was performed to compare differences in anti-double-stranded DNA (anti-dsDNA) levels between patients with positive and negative anti-histone antibodies (anti-H). <h3>Results:</h3> Nineteen patients were included, mostly female (n=14). The mean age at the diagnosis of LE-like syndrome was 45.42 (±16.77) years. Ten IBD and 2 RD patients received infliximab. At the time of symptoms onset, anti-TNF agent was discontinued. Fifteen (78.9%) patients developed polyarthritis and 3 (15.8%) polyarthralgias. Three (15.8%) patients had constitutional symptoms (such as fatigue or fever), 2 (10.5%) patients developed skin rash, 2 (10.5%) patients had cytopenia (1 with anemia and 1 with anemia and leukopenia; both in RD group), 2 (10.5%) patients developed serositis (pleural effusion) and 1 (5.3%) patient had vasculitis-like skin lesions in the hands; 1 (5.3%) patient developed venous thrombosis associated with antiphospholipid antibodies positivity. At the time of LE-like syndrome diagnosis, all patients (n=100, 19%) tested positive for antinuclear antibodies (ANA), and almost all patients (n=14, 73.7%) tested positive (≥100 international units/L) for anti-dsDNA. Except for 4 (21.1%) patients (3 in IBD group and 1 in RD group) who had low complement (C3c/C4), complement levels were mostly normal. The relevant data are detailed in Table 1. Of note, positive anti-H were accompanied by low serum levels of anti-dsDNA antibodies, p&lt;0.001 (Table 2). Seven (36.8%), all IBD patients, needed immunosuppressive therapy (methotrexate, azathioprine or hydroxychloroquine) to resolve their LE-like syndrome symptoms (in 3 patients, anti-dsDNA were negative only after at least 1 year of treatment) and continued to receive immunosuppressants during follow-up. In 11 (57.9%) cases, including all RD patients, discontinuation of anti-TNF therapy (and sometimes using low dose of glucocorticoids) was sufficient for symptoms resolution and antibody negativity. Five patients (26.3%) switched to another anti-TNF without experiencing relapse of symptoms. <h3>Conclusion:</h3> Studies show that SLE-like syndrome frequency has been increasing and recognition of the condition is very important as anti-TNF therapy is commonly used. This study, although limited by its descriptive nature and small sample size, revealed differences between the RD and IBD groups regarding the specific anti-TNF agents used and the necessity of immunosuppressive therapy, more prevalent in the IBD group. On the other hand, most patients improved after discontinuing therapy and those who tolerated the switch to another anti-TNF-α agent had no SLE recurrence. Of interest, positive anti-H was associated with absence or low levels of anti-dsDNA, suggesting that this clinical entity is an independent disease and different from classical drug-induced lupus with positive anti-histone antibodies. Further studies are required to establish definite differences between IBD and RD groups and determine the impact of definitive SLE diagnosis secondary to anti-TNF therapy. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> <b>None declared.</b>