HLA-B27 Uveitis is the Most Common Type of Uveitis in Ethnic Chinese

HLA-B27-associated uveitis is the most common type of endogenous uveitis in the ethnic Chinese population. The typical presentation of HLA-B27 uveitis is acute anterior uveitis (AAU). AAU has been defined as a sudden onset of pain, redness, and photophbia associated with anterior chamber cells and flare ≥ 1+, the duration of which is less than 3 months. Recurrence of AAU with an alternating unilateral attack is an important characteristic. Same eye attacks occur at greater than the expected percentage as compared with attacks with a random eye occurrence. A high number of attacks clustered in the cold winter season is found. HLA-B27 uveitis is strongly associated with spondyloarthritis (SpA). SpA was confirmed in 387 of 504 patients (76.8%) with HLA-B27 uveitis in our clinic from 1987 to 2004. Among them, ankylosing spondylitis occurred in 42.5%, with a significantly higher frequency in males than female. Undifferentiated SpA occurred in 29.8%, with a significantly high incidence in females. Reactive arthritis occurred in 2.2%, psoriatic arthritis in 2.0%, and enteropathic arthritis in 0.4%. A comparison of patients with and without SpA revealed a significantly younger age at the first attack of uveitis in patients with SpA. Keywords: Uveitis, HLA-B27, ankylosing spondylitis, spondyloarthritis, psoriatic arthritis