Background Adult onset Still’s disease (AOSD) is a rare inflammatory disorder of unknown etiology that classified into three patterns. The treatment of AOSD has been empirical and the information predicted outcome is lack.

Objectives The objective of this study is to evaluate the clinical features and responses to therapy in Korean AOSD patients.

Methods We retrospectively reviewed medical records of one hundred thirty-seven Korean patients with AOSD satisfied Yamaguchi’s criteria at one tertiary hospital from 2005 to 2011.

Results 83.3% was female, and the average age of diagnosis is 37.1 years old. Median period of follow-up is 59.0 months. Thirty-seven patients (27.0%) are monocyclic, sixty-eight patients (49.6%) are polycyclic and thirty-two patients (23.4%) are chronic articular pattern. Clinical manifestations were: fever 89.8%, arthritis 66.4%,evanescent rash 62.8%, abnormal liver function test 62.8%, leukocytosis 55.3%, hyperferritinemia 43.1%, myalgia 38% and sore throat 35.8 et al. There was no correlation between disease pattern and clinical manifestations except level of serum ferritin between monocyclic and polycyclic pattern. Average of modified Pouchot’s score at disease onset was 4.9±1.7 and statistically correlated with monocyclic and polycyclic patterns. Prescriptions were: glucocorticoid (GC) 80.9%, methotrexate (MTX) 73.8%, leflunomide 34%, cyclosporine (CsA) 32.6%, hydroxychloroquine (HCQ) 26.2%, azathioprine (AZA) 5.7%, anti-TNF blockers 7.8% (etanercept 5, adalimumab 2, infliximab 6) and intravenous immunoglobulin 3.5%. Almost patients were treated with combination of GC and/or immune suppressants. Combination of MTX and GC were 18%. The rates of these combination plus additional leflunomide, CsA or HCQ were 20.3%, 17.6% and 9.5% respectively. The rates of combination were GC with CsA 7.2%, GC with HCQ 2.7%, GC with leflunomide 1.8% and GC with AZA 1.4% respectively. The response rates were GC 76.1%, MTX 70.2%, leflunomide 68.8%, CsA 52.3 and anti-TNF blocker 72.7%. Four cases made an attempt to treat with anakinra or tocilizumab. GC response was correlated with disease remission (p-value <0.017). MTX and leflunomide were effective at GC responders in polycylic and chronic articular patterns. CsA was not effective in the presence of arthritis, especially chronic articular pattern (p-value <0.008).

Conclusions Polycyclic pattern of AOSD is more common in this study. Ferittin and modified Pouchot’s score could be considered as predictors of disease pattern but not sufficient. GC and MTX were effective treatments like previous studies. Additionally leflunomide could be used effectively in the presence of arthritis in combination with MTX rather than CsA.

Disclosure of Interest None Declared