POS1344 EVALUATING THE MULTIVISCERAL INVOLVEMENT ON ADULT-ONSET STILL’S DISEASE TO RETRIEVE IMAGING-BASED DIFFERENCES IN PATIENTS WITH AND WITHOUT MACROPHAGE ACTIVATION SYNDROME; RESULTS FROM A SINGLE-CENTRE OBSERVATIONAL STUDY

Background: Adult-onset Still’s disease (AOSD) is a rare systemic inflammatory disorder usually affecting young adults, burdened by life-threatening complications, mainly macrophage activation syndrome (MAS), secondary form of hemophagocytic lymphohistiocytosis [1]. In this context, the importance an accurate assessment AOSD suggested to promptly recognise multivisceral involvement which associated with complications. The most aggressive subsets could guide clinicians when apply additional resources but avoiding unnecessary expenditures in patients less severe clinical picture. Objectives: study, we aimed at describing retrieve imaging-based differences and without MAS. Methods: present evaluation has been designed as cross-sectional study descriptively compare Patients admitted our Institution, who underwent total body CT scan, were selected from historical cohort assessed. Clinical scan characteristics MAS compared. analysed parametric or non-parametric t tests for all continuous variables, chi squared test was used categorical ones, appropriate. Furthermore, possible correlations among radiological outcomes laboratory markers score estimated using point-biserial coefficient correlation. Results: This evaluated 39 (men 64.1%), mean age 48.8±16.6 years). Out those, 14 (35.9%) complicated These showed higher values ferritin [AOSD: 770.0 (1306.5) ng/mL vs MAS: 2926.3 (4918.5) p=0.003] (AOSD: 4.6±1.4 6.9±1.7, p<0.0001). presented prevalence lung than others 56.0% 85.7% p=0.048). Lung correlated (coefficient 0.491, p=0.003). more frequently characterised hepatomegaly 12.0% 50.0% p=0.019) splenomegaly 16.0% p=0.033), respectively, others. Hepatomegaly CRP 0.421, p=0.016), 0.397, p=0.020), 0.391, p=0.022). presence 0.439, p=0.009). features abdominal effusions observed those complication 57.1% p=0.007). Finally, percentage significant lymph node enlargement, either mediastinal abdominal, on 36.0% 71.4% lymphadenomegaly 0.368, p=0.032). Conclusion: Our findings multiorgan MAS, suggesting differences, although other studies are needed fully assess issue. Pulmonary disease, hepatomegaly, splenomegaly, nodes these patients. References: [1]Giacomelli R, Ruscitti P, Shoenfeld Y. A comprehensive review adult onset disease. J Autoimmun. 2018 Sep;93:24-36. Disclosure Interests: None declared