Anterior uveitis
Inflammation of the iris and ciliary body causes a painful, photophobic red eye with an irregular pupil and visual blurring, reflecting immune-mediated attack on the anterior uvea and often signalling an underlying systemic disease.
First principles
The disease is immune-mediated inflammation of the iris and ciliary body
Anterior uveitis is inflammation of the iris (iritis) and/or ciliary body (cyclitis), most often triggered by an autoimmune or HLA-B27-associated process, less commonly by infection. Inflammatory cells and protein leak into the aqueous humour, producing 'cells and flare' visible at the slit lamp. This is a deeper structure than the conjunctiva, which is why the disease behaves so differently: it is painful, sight-threatening, and does not simply settle with lubricants.
Educational content pending clinical review. Not medical advice.