POS0074 CAN WE PREDICT THE DEVELOPMENT OF NEPHRITIS IN PEDIATRIC IGA VASCULITIS PATIENTS?

Background: IgA vasculitis (IgAV) is the most common systemic of childhood, characterized by palpable purpura, arthritis, gastrointestinal and renal involvement 1 . It a relatively self-limited disease apart from which associated with long term morbidity. Objectives: We aimed to define marker at onset predict involvement. Methods: In this pilot study, we analyzed targeted panel vascular inflammation markers (sT2, RAGE, TIE-2, sCD40L, TIE-1, sFlt-1, LIGHT, TNF-a, PlGF, IL6, IL18, IL10 MCP-1) in plasma samples eight patients IgAV disease, before any treatment was initiated. At time sample collection, none had involvement; four these subsequently developed nephritis were defined as IgAVN group. The levels studied cytometric bead-based multiplex assay according manufacturer’s instruction (LEGENDplex HU Vascular Inflammation 2 (13-plex); catalogue number 740966, Biolegend) Novocyte 3005 flow cytometer. Results: There no significant differences gender, age, clinical manifestations, laboratory findings between (Table 1). sCD40L higher (median 1938.1 vs 754.9 pg/mL, p=0.04) whereas sST2 lower 862.8 2302.8 p=0.02) who (Figure sRAGE IL18 but did not reach statistical significance, probably due low patients. other parameters show specific pattern. Table 1. (n=4) p value Gender 2F, 2M 1F, 3M 0.49 Age 9.0±5.4 10.3±3.4 0.68 Arthralgia/arthritis 50% 75% GIS Haemoglobine (gr/dL) 12.4±2.3 12.3±0.6 0.95 White blood cells, x10 9 /L 11150±1933 8525±1497 0.08 Platelets 290250±87328 269250±38741 Erythrocyte sedimentation rate (mm/hr) 10.5±9.1 21.0±14 0.26 C-reactive protein (mg/dL) 0.63±0.03 1.16±0.96 0.39 Data are given mean±SD Figure Soluble CD40 ligand (sCD40L) expressed on platelets released activation. proinflammatory for endothelial cells promotes coagulation inducing expression tissue factor monocytes investigated acute coronary syndrome suggested risk damage. Furthermore, shown be correlated activity ANCA-associated 3 Thus IgAV, may kidney vasculature, represents more severe form disease. Receptor advanced glycation end-products (RAGE) another damage IgAVN, well. IL33 epithelial overexpression have been large vessel 4 acts decoy receptor inhibits signalling interesting see that IL-18 sST2, members IL-1 family, Conclusion: Although limited suggest might used development Further studies larger needed confirm our findings. References: [1]Sag E, Batu ED, Ozen S. Childhood vasculitis. Best practice & research Clinical rheumatology 2017;31(4):558-75. [2]Heeschen C, Dimmeler S, Hamm CW, et al. syndromes. New England journal medicine 2003;348(12):1104-11. [3]Tomasson G, Lavalley M, Tanriverdi K, Relationship platelet activation Wegener’s granulomatosis. Journal 2011;38(6):1048-54. [4]Desbois AC, Cacoub P, Leroyer AS, Immunomodulatory role Interleukin-33 Sci Rep 2020;10(1):6405. Disclosure Interests: None declared.