Uveitis in children — formative SAQs

Short Answer Question 1 (10 marks)

A four-year-old girl with oligoarticular, ANA-positive juvenile idiopathic arthritis diagnosed one month ago attends her routine three-monthly slit-lamp screening. The ophthalmologist reports grade 2+ cells and 1+ flare in both anterior chambers, with a few keratic precipitates but no posterior synechiae, no band keratopathy and normal intraocular pressure. The child is asymptomatic with white eyes. ^{[7] [3]}

a) Explain the pathophysiology of the slit-lamp findings and why this disease is clinically silent. (3 marks) ^[2]

Breakdown of the blood-aqueous barrier by autoreactive T-helper-1 and T-helper-17 lymphocytes allows protein (flare) and inflammatory cells (cells) to leak into the anterior chamber — the slit-lamp findings. The disease is silent because the anterior chamber inflammation produces no pain, no redness and no visual symptom in the early and moderate stages, and the visually immature child cannot report what they cannot perceive. ^{[2] [1]}

b) Outline the stepwise management from this point, naming agents, doses and the escalation triggers. (5 marks) ^{[2] [7]}

Step one is topical prednisolone acetate 1% eye drops (every one to two hours initially, tapering on slit-lamp review) plus cycloplegia with atropine 1% or cyclopentolate 1% to prevent posterior synechiae. ^{[2] [7]}

Step two — systemic methotrexate 10 to 15 mg per square metre per week (oral or subcutaneous) with folic acid — is indicated if the uveitis is not controlled by topical steroid alone, or if the child becomes corticosteroid-dependent or develops steroid complications. ^[2]

Step three — biologic adalimumab 24 mg per square metre subcutaneously every two weeks (maximum 40 mg per dose) for children aged two years and older — is indicated for disease resistant to or dependent on methotrexate, anchored by the SYCAMORE trial evidence. ^{[5] [7]}

c) Name the five sight-threatening complications that this treatment is designed to prevent, and explain why childhood uveitis blinds more readily than adult uveitis. (2 marks) ^{[1] [4]}

Band keratopathy, cataract, secondary glaucoma, posterior synechiae and amblyopia. Childhood uveitis blinds more readily because any media opacity during the visually immature period causes amblyopia — permanent cortical visual deprivation that persists even if the structural disease is later treated. ^{[1] [4]}