Purpose To investigate etiologic data on intraocular inflammation in Japan collected in the 2009 epidemiologic survey of uveitis in Japan and assess the current state of etiology compared with that reported in a previous survey. Methods Thirty-six university hospitals participated in this prospective etiologic study. Patients who visited the outpatient uveitis clinic of each hospital for the first time between 1 June 2009 and 31 May 2010 were enrolled in the study. Uveitic diseases were diagnosed according to the guidelines when available or following commonly accepted diagnostic criteria. Results A total of 3,830 patients were enrolled in the survey and 2,556 cases of uveitis were identified, of which 1,274 cases were described as unclassified intraocular inflammation. In the identified cases, the most frequent intraocular inflammatory disease was sarcoidosis (10.6 %), followed by Vogt-Koyanagi-Harada disease (7.0 %), acute anterior uveitis (6.5 %), scleritis (6.1 %), herpetic iridocyclitis (4.2 %), Behcet's disease (3.9 %), bacterial endophthalmitis (2.5 %), masquerade syndrome (2.5 %), Posner-Schlossman syndrome (1.8 %), and retinal vasculitis (1.6 %). Conclusions The current etiology of uveitis in Japan was elucidated by means of a multi-center prospective survey. Conducting such surveys on a periodic basis may help clinicians in their management of uveitis.
All Science Journal Classification (ASJC) codes