Uveitis in children — branching viva

Candidate instructions (8-minute structured oral)

You are the general paediatric registrar in the outpatient clinic. A four-year-old girl with oligoarticular ANA-positive juvenile idiopathic arthritis diagnosed three months ago is found on her routine three-monthly screening slit-lamp to have grade 2+ cells and 1+ flare in both anterior chambers. Her eyes are white and she is asymptomatic. Take the examiner through your approach. [7] [1]

Opening branch — classification and recognition

Examiner: What is uveitis, and how is it classified? How does this child's presentation fit? [1]

Uveitis is inflammation of the uveal tract — the iris, ciliary body and choroid. The SUN anatomical classification sorts it into anterior (iritis, iridocyclitis), intermediate (pars planitis), posterior (retinitis, choroiditis) and panuveitis. This child has bilateral chronic anterior uveitis — the form overwhelmingly associated with JIA, and the commonest childhood uveitis in developed settings. [1] [3]

Examiner: Why was this found on screening rather than by symptoms? [7]

JIA-associated anterior uveitis is characteristically silent: a white eye, no pain, no redness, no photophobia, no visual complaint. The inflammation is inside the anterior chamber, and only slit-lamp examination can detect the cells and flare. The disease blinds because it smoulders for months to years without any symptom to prompt presentation. [7] [3]

Branching to pathophysiology

Examiner: Explain the pathophysiology of the slit-lamp findings. [2]

Non-infectious anterior uveitis is a T-cell mediated autoimmune process. Autoreactive CD4-positive T-helper-1 and T-helper-17 lymphocytes breach the blood-aqueous barrier. Protein leaks into the aqueous (flare) and inflammatory cells enter (cells), and the slit-lamp beam reveals both. Persistent inflammation then drives the structural complications: fibrin causes posterior synechiae, calcium deposits as band keratopathy, the lens opacifies as cataract, and the trabecular meshwork scars to produce secondary glaucoma. [2] [1]

Branching to management

Examiner: How would you manage this child, step by step? [2] [7]

Step one is topical prednisolone acetate 1% eye drops — every one to two hours initially for moderate disease, tapering on slit-lamp review — with cycloplegia using atropine 1% or cyclopentolate 1% to immobilise the iris and prevent posterior synechiae. Before any topical steroid is prescribed, the ophthalmologist excludes herpes simplex keratitis by slit-lamp and fluorescein, because steroid causes corneal melting in herpetic disease. [2] [7]

Examiner: What if the inflammation does not settle on topical therapy alone? [5]

Step two is systemic methotrexate 10 to 15 mg per square metre per week (oral or subcutaneous) with folic acid supplementation. Methotrexate is the first-line systemic agent and takes two to three months for full effect. Step three, for disease resistant to or dependent on methotrexate, is biologic adalimumab 24 mg per square metre subcutaneously every two weeks — the evidence comes from the SYCAMORE trial, which showed adalimumab plus methotrexate reduced treatment failure in JIA-associated uveitis. [5] [7]

Branching to complications and screening rationale

Examiner: Name the five complications you are trying to prevent. [1] [7]

Band keratopathy, cataract, secondary glaucoma, posterior synechiae and amblyopia. The last is the most devastating — any media opacity during the visually immature period causes permanent cortical visual deprivation that persists even if the structural disease is later treated. This is why screening exists: to detect inflammation before these complications develop. [1] [7]

Examiner: Why does this child need screening every three months? [7]

The 2019 ACR and Arthritis Foundation guideline stratifies screening by risk. This child is high risk: ANA positive, oligoarticular JIA, onset under seven years, disease duration under four years. High-risk children are screened every three months for the first four years. The interval extends with longer disease duration and older age. [7]

Closing branch — the red eye and the differential

Examiner: How would your approach differ if a fourteen-year-old boy presented with a sudden red painful eye and photophobia? [8] [2]

This is the acute anterior uveitis pattern of HLA-B27-associated spondyloarthritis — a very different tempo from the chronic JIA form. Examine by slit-lamp and fluorescein (excluding herpes simplex keratitis), confirm cells and flare, treat with intensive topical prednisolone acetate 1% and cycloplegia, and refer to rheumatology for the underlying enthesitis-related arthritis — examine the sacroiliac joints, the Achilles tendon and plantar fascia insertions, and ask about inflammatory back pain and bowel symptoms. [8] [9]