Inflammation

Importance: Uveitis is characterized by inflammation of the uvea—the middle portion of the eye composed of the iris, ciliary body, and choroid—causing eye redness, pain, photophobia, floaters, and blurred vision. Untreated uveitis may cause cataracts, glaucoma, macular edema, retinal detachment, optic nerve damage, and vision loss.

Observations: Uveitis predominantly affects individuals aged 20 to 50 years. Anterior uveitis affects the iris and ciliary body (41%-60% of cases); intermediate uveitis affects the pars plana (attachment point of vitreous humor) and peripheral retina (9%-15%); posterior uveitis involves the choroid and/or retina (17%-23%); and panuveitis involves all uveal layers (7%-32%). Uveitis is classified as noninfectious or infectious, with toxoplasmosis, herpes, tuberculosis, and HIV comprising 11% to 21% of infectious cases in high-income countries and 50% in low- and middle-income countries. Incidence and prevalence of uveitis are influenced by genetic factors (eg, human leukocyte antigen–B27), environmental factors (eg, air pollution), and infection rates. In the US and Europe, 27% to 51% of uveitis cases are idiopathic, and 37% to 49% are associated with systemic disease, such as axial spondyloarthritis. Treatment goals are to induce and maintain remission while minimizing corticosteroid use to reduce corticosteroid-related adverse effects. Infectious uveitis requires systemic antimicrobial treatment. Active inflammatory disorders associated with uveitis should be treated by the appropriate specialist (eg, rheumatologist). Treatment for uveitis depends on subtype; anterior uveitis is treated with topical corticosteroids, and mild intermediate uveitis may be monitored without initial treatment. Patients with moderate to severe intermediate uveitis, posterior uveitis, and panuveitis are at high risk of sight-threatening complications and require systemic and/or intravitreal corticosteroids and immunosuppressive agents. For posterior uveitis, first-line therapy with disease-modifying antirheumatic drugs such as methotrexate achieved remission of inflammation in 52.1% (95% CI, 38.6%-67.1%) of patients, and mycophenolate mofetil controlled inflammation in 70.9% (95% CI, 57.1%-83.5%). In patients who do not improve or worsen with first-line therapy, adalimumab extended time to treatment failure to 24 weeks vs 13 weeks with placebo and reduced frequency of treatment failure from 78.5% to 54.5% (P < .001).

Conclusions and Relevance: Uveitis is characterized by inflammation of the uvea and primarily affects adults aged 20 to 50 years. For noninfectious anterior uveitis, corticosteroid eyedrops are first-line treatment. For posterior noninfectious uveitis, disease-modifying antirheumatic drugs are first-line therapy; biologics such as adalimumab are second-line treatment for patients with inflammation refractory to treatment. Uveitis caused by systemic infection should be treated with antimicrobials, and local or systemic steroids may be used depending on the severity of uveitis and the specific microorganism.