What is new HLA-B27 acute anterior uveitis?

Acute anterior uveitis (AAU) is the most common form of uveitis, accounting for approximately 90% of all cases. Half of all cases of AAU are HLA-B27 positive. The disease is typically acute in onset, unilateral, nongranulomatous inflammation involving the iris and ciliary body, with a tendency to recurrent attacks. Approximately 50% of all patients with HLA-B27 AAU develop an associated seronegative arthritis (SNA), while approximately 25% of the patients initially diagnosed with HLA-B27 SNA develop AAU. Environmental factors play a critical role in the pathogenesis of AAU; in particular, bacterial triggers have been strongly implicated in the development of this disease. Topical corticosteroids and cycloplegic agents remain the cornerstones of treatment for AAU. Salazopirine and methotrexate are effective in decreasing recurrent attacks. Biological agents such as anti-TNF and anti-CD20 therapy may be effective in refractory severe AU but are rarely required.