AB1484 ADULT-ONSET STILL’S DISEASE AND SYSTEMIC JUVENILE IDIOPATHIC ARTHRITIS: PREDICTORS OF DRUG-FREE REMISSION IN A MONOCENTRIC COHORT

Background Adult-onset Still’s disease (AOSD) and Systemic Juvenile Idiopathic Arthritis (SJIA, formerly termed Disease), are rare polygenic autoinflammatory disorders of unknown etiology. The clinical course AOSD/SJIA has been distinguished into different phenotypes, described on the basis evolution symptoms over time. In a sizeable proportion affected patients, remission can be achieved with treatments, that progressively tapered stopped without relapse. Not much information is available drug-free predictors. Objectives To look for predictors in retrospective monocentric cohort AOSD/SIJA patients. Methods Retrospective evaluation patients followed up an Italian Rheumatology Unit between January 1997 September 2022. All fulfilled Yamaguchi criteria or PRINTO preliminary criteria. Drug-free was defined as absence laboratory markers activity treatment at least 6 months. Differences who not were assessed using Mann-Whitney test, Student’s t-test, Chi-squared test Fisher when appropriate. Results 57 AOSD 7 SIJA consecutive included study. 23 (35.9%) after median period 3,62 years (IQR 1,37 – 6). Their main baseline demographic features, well received summarized Table 1. Patients group more often had white blood cells count >15.000/uL (p:0.004) than other On contrary, failed frequently treated Cyclosporine A (CyA) onset (p:0.042). No significant difference observed analyzing if csDMARDs bDMARDs started within 3 months not. Conclusion Hyperleukocytosis identified potential predictor our while this difficult to obtain CyA onset. Larger collaborative studies needed confirm better define these results. References [1]Yamaguchi M et al. J Rheumatol. 1992 Mar;19(3):424-30. PMID: 1578458. [2]Martini 2019 Feb;46(2):190-197. Baseline features n: 41 p-value n (%) 20 (87.0%) 37 (89.2%) 0.69 Male 12 (52.2%) 14 (34.2%) 0.16 Age onset, Mean±SD 30.5 ±13.6 36.6 ±15.4 0.12 Follow-up duration, Median (IQR) 6.5 (2.7–10.7) 8.6 (3.5-15.3) 0.94 Ferritin mg/mL 1766 (682-11594) 1255 (551-6620) 0.61 WBC >15000/uL (% ) 15 (71.4% 13 (32.5% 0.0037 WBC/uL 17337 ±8223 14562 ±5995 0.14 Hb g/dl 10.9 ±1.8 11.3 ± 1.8 0.37 PLTx10 /uL 325.30 ±171.97 328.74 ±135.6 0.93 CRP mg/L 130.8 ±79.1 143.2 ±108.6 0.65 ALT U/L 68 (32-122) 59 (25 -117) 0.40 AST 44 (22-90) 49 (27 -90) 0.26 Modified Pouchot’s score, 6.1 ±1.46 6.6 ±1.73 0.24 MAS 2 (8.7%) 5 (12,2%) 1 Treatment (within since onset), 9 (39.1%) (56.1%) 0.3 cyclosporine 0 8 (19.5% 0.04 b/tsDMARDS (75%) (34.6%) 0.27 Legend: White Blood Cell; Hemoglobin, PLT Platelets, C-Reactive Protein, Alanine Transaminase, Aspartate Macrophage Activation Syndrome, conventional Disease-Modifying Antirheumatic Drugs, b/tsDMARDs biological/targeted synthetic Drugs Acknowledgements: NIL. Disclosure Interests Giulia Fontana: None declared, Francesca Crisafulli: Micol Frassi Speakers bureau: Novartis, Lilly, marco Cattalini Consultant of: SOBI, Franco Franceschini: Paolo Airò Bristol Myers Squibb, Bohringer Ingelheim,