A nationwide survey was conducted to assess the number of patients, clinical aspects, treatment, and prognosis of adult Still's disease (ASD) in Japan.
A primary questionnaire was sent to randomly selected medical institutions in order to estimate the number of patients. We sent a secondary questionnaire to the same institutions to characterize the clinical manifestations and treatment of ASD.
The estimated prevalence of ASD was 3.9 per 100,000. Analysis of 169 patients showed a mean age at onset of 46 years. The main clinical symptoms were fever, arthritis, and typical rash in agreement with previous surveys. Oral glucocorticoids were used to treat 96% of the patients, while methotrexate was used in 41% and biological agents were used in 16%. Lymphadenopathy and macrophage activation syndrome were significantly associated with increased risk of relapse (P < 0.05, each). Patients who achieved remission after tocilizumab therapy had significantly longer disease duration (6.2 years) than patients who did not (1.9 years) (p < 0.05).
The 2010-2011 nationwide survey of ASD identified important changes in treatment and improvement of prognosis compared with previous surveys.