Background Adult-onset Still's disease (AOSD) is an inflammatory disease characterized by fever, arthritis and typical, salmon-colored rash which is more pronounced and is accompanied by increased fever at nights. Currently, there is limited data on the prevalence of AOSD.Currently, there is limited data on the frequency of AOSD. Studies based on questionnaire data have reported an annual AOSD incidence of 0.22/100,000 in Japan  and 0.16/100,000 in France . A study using hospital-based database has found an annual AOSD incidence of 0.4/100,000 in Northern Norway .
Objectives In our study, we aimed to determine the epidemiology, general clinical features and outcomes of AOSD on the basis of hospital-based data in Thrace, the northwestern region of Turkey. We also evaluated other epidemiological studies and major series as a systematic review.
Methods Patients diagnosed with AOSD at the Rheumatology Department of the Medical Faculty of Trakya University between 2003 and 2014 were reviewed retrospectively. Patients' clinical features, laboratory measurements, demographics, received treatments, follow-up durations, disease courses, outcomes and complications were evaluated.
Results Our study included 42 patients with AOSD. Of them, 32 (76.2%) were females and 10 (23.8%) were males (female to male ratio: 3.2). Over the course of the study, the annual incidence of AOSD was 0.62/100,000 and the overall prevalence was 6.77/100,000. The most common findings were fever (97.6%), arthralgia (95.2%), arthritis (76.2%), rash (73.8%) and sore throat (40.5%).
Conclusions In conclusion, in our hospital-based study on AOSD as a condition with very limited epidemiological data, AOSD frequency was significantly higher compared to other series. Female gender was more common in our series with predominantly monocyclic pattern in relation to follow-up period compared to other series.
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Disclosure of Interest None declared