Uveitis

Overview

•Painful red eye - unilateral; deep aching pain from ciliary muscle spasm

•Photophobia - consensual; ciliary spasm triggered by pupillary light reflex

•Reduced visual acuity - inflammatory cells and flare obscuring visual axis

•Lacrimation

•Ciliary flush - deep red/violet ring at the limbus

•Small, irregular pupil (miosis) - ciliary spasm causes constriction; posterior synechiae cause irregularity

•Hypopyon - visible layer of pus (white cells) settling in inferior anterior chamber; indicates severe inflammation

•Keratic precipitates - clumps of inflammatory cells on corneal endothelium (slit-lamp)

Anterior uveitis vs acute angle-closure glaucoma
FeatureAnterior uveitisAcute angle-closure glaucoma
PupilSmall, irregular, fixedSemi-dilated, fixed, oval
CorneaClearHazy
PainDeep achingSevere; headache, nausea
Visual symptomsReduced VA, photophobiaReduced VA, halos around lights
TreatmentSteroids + cycloplegicsAcetazolamide + pilocarpine

Feature	Anterior uveitis	Acute angle-closure glaucoma
Pupil	Small, irregular, fixed	Semi-dilated, fixed, oval
Cornea	Clear	Hazy
Pain	Deep aching	Severe; headache, nausea
Visual symptoms	Reduced VA, photophobia	Reduced VA, halos around lights
Treatment	Steroids + cycloplegics	Acetazolamide + pilocarpine

Investigations

•Clinical diagnosis - slit-lamp examination is key: anterior chamber cells, flare, hypopyon, posterior synechiae, keratic precipitates

•Intraocular pressure - normal/low in anterior uveitis (helps exclude AACG)

•HLA-B27 testing - if associated back pain, arthritis, or recurrent attacks

•ESR, CRP - non-specific inflammatory screen

•Chest X-ray - screens for sarcoidosis (bilateral hilar lymphadenopathy) and TB

Management

🚨
Anterior uveitis must never be left untreated - urgent ophthalmology review is required to prevent permanent visual loss.

🥇 First-line

•prednisolone acetate 1% eye drops - suppresses anterior chamber inflammation; titrate frequency to severity

•cycloplegic (mydriatic) eye drops - cyclopentolate 1% or atropine 1% - relieves ciliary spasm (reduces pain/photophobia) and prevents posterior synechiae formation

🥈 Second-line

•periocular or systemic corticosteroids - severe, refractory, bilateral, or posterior segment involvement

•systemic immunosuppression - methotrexate, mycophenolate mofetil, or azathioprine for chronic/recurrent/steroid-dependent disease

🥉 Third-line

•adalimumab - licensed for non-infectious intermediate, posterior, and panuveitis; when conventional immunosuppression fails

•Treat underlying cause - e.g. antivirals for herpetic uveitis

⚠️
Pilocarpine must NEVER be used in anterior uveitis - it constricts the pupil and worsens synechiae formation and ciliary spasm. It is reserved for acute angle-closure glaucoma.

Complications

•Posterior synechiae - iris adheres to anterior lens; fixed irregular pupil; if circumferential, blocks aqueous flow

•Secondary glaucoma - raised IOP from impaired aqueous outflow

•Cataract - chronic inflammation or prolonged steroid use (posterior subcapsular)

•Cystoid macular oedema - most common cause of visual loss in uveitis

•Band keratopathy - calcium deposits across cornea; especially in JIA

Systemic associations

•HLA-B27-associated (most common exam association): ankylosing spondylitis, reactive arthritis, psoriatic arthritis, IBD

•Sarcoidosis - bilateral hilar lymphadenopathy on CXR; raised ACE

•JIA - silent chronic anterior uveitis, no redness or pain; requires regular slit-lamp screening

•Infectious - herpetic, toxoplasmosis, syphilis, TB