Uveitis refers to inflammation of the uveal tract, which may be idiopathic, infective or inflammatory ¹. It is a sight threatening condition that requires urgent ophthalmologist review.

Epidemiology

Incidence estimates vary widely, with one meta-analysis suggesting a pooled incidence of 50.45 per 100,000 (with individual studies estimating as high as 340.9 per 100,000 per year) ².

Clinical presentation

Clinical symptoms are non-specific and include eye pain, photophobia, and reduced visual acuity ³.

Slit lamp and fundoscopic examination may demonstrate flare in the anterior chamber and cells in the vitreous chamber ³.

Pathology

Inflammation may affect any part or all of the uveal tract (the iris, ciliary body and choroid). Anatomical localization of the process correlates with potential etiology ¹:

• anterior (anterior chamber): idiopathic or non-infective inflammatory disease (e.g. sarcoidosis)

• intermediate (posterior ciliary body and pars plana): usually idiopathic, may be associated with multiple sclerosis

• posterior (choroid): typically infectious (e.g. toxoplasmosis or tuberculosis) or non-infectious systemic inflammatory disease

• panuveitis (entire uveal tract): sarcoidosis, Lyme borreliosis, tuberculosis, and syphilis.

Associated non-infectious inflammatory diseases include ankylosing spondylitis, ulcerative colitis, rheumatoid arthritis, sarcoidosis, Behçet disease, relapsing polychondritis and Vogt-Koyanagi-Harada (VKH) disease ¹. Rare associations include Blau syndrome ⁴ and Kikuchi-Fujimoto disease ⁵.

Radiographic features

CT

Less sensitive than MRI. May show uveoscleral thickening and enhancement ¹.

MRI

MRI is the modality of choice if imaging is required ¹. Typically increased enhancement and/or thickening of the affected uveal tract is seen ^1,3.

• T1:

  • thickened affected uveal tract

  • may see altered vitreous signal

• T2:

  • thickened affected uveal tract

  • may demonstrate retinal detachment or subretinal effusions

• FLAIR: very sensitive to altered vitreous signal (hyperintense)

• T1 C+: marked enhancement of the affected uveal tract (compare to unaffected side if unilateral), usually smooth but can be nodular (uncommon and needs careful assessment to distinguish from tumor)

• DWI/ADC: abnormal restricted diffusion is usually not a feature, however, occasionally may see abnormal restricted diffusion of the uvea and subretinal effusions

Treatment and prognosis

Treatment is etiology-specific ³.

Non-infectious inflammatory causes are primarily treated with corticosteroids (topical, intraocular or intravenous) ¹. Immunosuppression may be required in severe or refractory cases ¹.

If infectious, appropriate antibiotic, antiviral or antifungal therapy is needed.

Prognosis is dependent upon etiology and initiation of treatment. Early detection and appropriate effective treatment is required to preserve vision.

Differential diagnosis

• scleritis

• endophthalmitis

• panophthalmitis

See also

• orbital pathology