AB1285 Serum interleukin 33, a possible new marker predicting the development of vasculitis in patients with systemic lupus erythematosus
Authors: A. A.-R. Youssef, A.E.M.A. Afify, T.O. El-Said, S.S. Metwaiiy, D.M. Abd El Ghafar
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> Systemic lupus erythematosus (SLE) is an autoimmune disease characterised by abnormal production of autoantibodies and proinflammatory cytokines. Although interleukin-33 (IL-33), a novel member of the IL-1 family, has been reported to have proinflammatory effects, the association of IL-33 with SLE has not been fully investigated<sup>1</sup> <h3>Objectives</h3> To estimate serum levels of IL- 33 in Egyptian patients with SLE and in controls, and to find out any relation between IL-33 serum levels in SLE patients and disease activity in addition to other clinical and laboratory criteria. <h3>Methods</h3> 60 SLE Egyptian patients (53 females and 7males) diagnosed according to systemic lupus international collaborating clinics (SLICC); new classification criteria 2012 and 20 healthy controls matched for age and sex were included. Patients with diseases suggesting the possibility of increased serum IL-33 were excluded<sup>2</sup> 27 SLE patients were diagnosed clinically as having vasculitis and this was confirmed by laboratory and imaging studies. Serum IL-33 was measured by sandwich ELISA Kit. Disease activity was assessed using SLE disease activity index (SLEDAI) score.<sup>3</sup> <h3>Results</h3> Using Mann-Whitney U test, median serum level of IL-33 (30.3 pg./ml) was significantly higher in patients with SLE than that of healthy controls (24.80, p=0.003). Using logistic regression analysis, SLE patients with high IL-33 serum levels have 3.8 times higher risk of developing vasculitis (OR 3.8 (1.1–13.6, 95% CI: p=0.01) and 3.2 times higher risk of developing oral ulcers (OR 0.3.2 (1.2–11.7, 95% CI: p=0.033.) than those with lower IL-33 serum Levels. No significant correlation was found between serum levels of IL-33 and total SLEDAI score or any of the other clinical or laboratory criteria. <h3>Conclusions</h3> Our findings suggest that IL-33 may be considered as a possible new inflammatory marker predicting the development of vasculitis and/or mucosal ulcers in SLE patients. Neutralisation of IL-33 may hopefully result in a new therapeutic option for these patients. Further studies are warranted to get more conclusive results. <h3>References</h3> [1] Yang, Z., Laing Y., Xi, W., Li, C., &amp; Zhong. R. Association of increased serum IL-33 Levels with clinical and laboratory characteristics of systemic lupus erythematosus in Chinese population. Clinical and Experimental Medicine2011;11(2):75–80. [2] Liew FY, Pitman NI, McInnes IB. Disease-associated functions of IL-33: the new kid in the IL-1 family. Nature Reviews Immunology2010;10(2):103–10. [3] Bombardier C, Gladman DD, Urowitz MB, Caron D, Chang CH, Austin A, Decker J. L Derivation of the SLEDAI. A disease activity index for lupus patients. Arthritis &amp; Rheumatology. 1992, 35(6), 630–640. <h3>Acknowledgements</h3> We acknowledge the efforts received by all staff members of departments of Rheumatology and clinical pathology at Mansoura University Hospital, Egypt. <h3>Disclosure of Interest</h3> None declared