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Overview of Uveitis


Kara C. LaMattina

, MD, Boston University School of Medicine

Reviewed/Revised Sep 2022
Topic Resources

Uveitis is defined as inflammation of the uveal tract—the iris, ciliary body, and choroid. However, the retina and fluid within the anterior chamber and vitreous are often involved as well. About half of cases are idiopathic; identifiable causes include trauma, infection, and systemic diseases, many of which are autoimmune. Symptoms include decreased vision, ocular ache, redness, photophobia, and floaters. Although uveitis is identified clinically, identifying the cause typically requires testing. Treatment depends on cause, but typically includes topical, locally injected, or systemic corticosteroids with a topical cycloplegic-mydriatic drug. Noncorticosteroid immunosuppressive drugs may be used in severe and refractory cases.

Uveitis is inflammation of the uveal tract (see figure Cross-section of the eye Cross-section of the eye  Cross-section of the eye ). Uveitis is classified anatomically as

  • Anterior uveitis: Localized primarily to the anterior segment of the eye, includes iritis (inflammation in the anterior chamber alone) and iridocyclitis (inflammation in the anterior chamber and anterior vitreous)

  • Intermediate uveitis: Localized to the vitreous cavity and/or pars plana (part of the ciliary body that extends posteriorly beyond the junction of the iris and sclera)

  • Posterior uveitis: Any form of retinitis, choroiditis, or inflammation of the optic disk

  • Panuveitis: Inflammation involving anterior, intermediate, and posterior structures

Uveitis is also classified by onset (sudden or insidious), duration (limited or persistent), and course (acute, recurrent, or chronic).

Cross-section of the eye

The zonules of Zinn keep the lens suspended, and the muscles of the ciliary body focus the lens. The ciliary body also secretes aqueous humor, which fills the anterior and posterior chambers, passes through the pupil into the anterior chamber, and drains primarily via the Schlemm canal. The iris regulates the amount of light entering the eye by adjusting the size of its central opening, the pupil. Visual images are focused on the retina. The conjunctiva covers the eyeball and lines the upper and lower eyelids; it ends at the limbus. The cornea is covered with epithelium that is more sensitive than and differs from the conjunctival epithelium.

Cross-section of the eye

Etiology of Uveitis

Causes of anterior uveitis include

Causes of intermediate uveitis include

Causes of posterior uveitis (retinitis) include

Causes of panuveitis include

Infrequently, systemic drugs cause uveitis (usually anterior). Examples are sulfonamides, bisphosphonates (inhibitors of bone resorption), rifabutin, cidofovir, and checkpoint inhibitors such as nivolumab and ipilimumab.

Symptoms and Signs of Uveitis

Symptoms and signs may be subtle and vary depending on the site and severity of inflammation.

Anterior uveitis tends to be the most symptomatic (especially when acute), usually manifesting with

  • Pain (ocular ache)

  • Redness

  • Photophobia

  • Decreased vision (to a variable degree)

Chronic anterior uveitis may have less dramatic symptoms and present with irritation or decreased vision.

Signs include hyperemia of the conjunctiva adjacent to the cornea (ciliary flush or limbal injection). Slit-lamp findings include keratic precipitates (white blood cell clumps on the inner corneal surface), cells and flare (a haze) in the anterior chamber (aqueous humor), and posterior synechiae. With severe anterior uveitis, white blood cells may layer in the anterior chamber (hypopyon).

Intermediate uveitis is typically painless and manifests with

  • Floaters

  • Decreased vision

The primary sign is cells in the vitreous humor. Aggregates and condensations of inflammatory cells often occur, appearing as "snowballs." Vision may be decreased because of floaters Floaters Floaters are opacities that move across the visual field and do not correspond to external visual objects. With aging, the vitreous humor can contract and separate from the retina. The age at... read more or cystoid macular edema, which results from fluid leakage from blood vessels in the macula. Confluent and condensed vitreous cells and snowballs over the pars plana (part of the ciliary body that extends posteriorly beyond the junction of the iris and sclera) may cause a classic "snowbank" appearance, which can be associated with neovascularization of the retinal periphery.

Posterior uveitis may give rise to diverse symptoms but most commonly causes floaters and decreased vision as occurs in intermediate uveitis. Signs include

  • Cells in the vitreous humor

  • White or yellow-white lesions in the retina (retinitis), underlying choroid (choroiditis), or both

  • Retinal vasculitis (with whitening or obliteration of blood vessels)

  • Optic disk edema

Panuveitis may cause any combination of the previously mentioned symptoms and signs.


Serious complications of uveitis include profound and irreversible vision loss, especially when uveitis is unrecognized, inadequately treated, or both.

The most frequent complications include

Diagnosis of Uveitis

  • Slit-lamp examination

  • Ophthalmoscopy after pupil dilation

Diagnosis of anterior uveitis is by recognizing cells and flare in the anterior chamber. Cells and flare are seen with a slit lamp and are most evident when using a narrow, intensely bright light focused on the anterior chamber in a dark room. Findings of intermediate and posterior uveitis are most easily seen after dilating the pupil. Indirect ophthalmoscopy Ophthalmoscopy The eye can be examined with routine equipment, including a standard ophthalmoscope; thorough examination requires special equipment and evaluation by an ophthalmologist. History includes location... read more (usually done by an ophthalmologist) is more sensitive than direct ophthalmoscopy. (NOTE: If uveitis is suspected, patients should be referred immediately for complete ophthalmologic evaluation.)

Acute angle-closure glaucoma Angle-Closure Glaucoma Angle-closure glaucoma is glaucoma associated with a physically obstructed anterior chamber angle, which may be chronic or, rarely, acute. Symptoms of acute angle closure are severe ocular pain... read more can cause redness and severe pain similar to that of uveitis, which is why it is important to check intraocular pressure at every visit. Uveitis is often (but not always) associated with a low intraocular pressure, whereas pressure is typically high in acute angle-closure glaucoma. Uveitis also can be distinguished from angle-closure glaucoma by the absence of corneal haze and the presence of a deeper anterior chamber.

Treatment of Uveitis

  • Corticosteroids (usually topical) and sometimes other immunosuppressive drugs

  • Cycloplegic-mydriatic drugs

  • Sometimes antimicrobial drugs

  • Sometimes surgical therapy

Treatment of active inflammation usually involves corticosteroids given topically (eg, prednisolone acetate 1% one drop as frequently as every hour while awake for severe inflammation) or by periocular or intraocular injection along with a cycloplegic-mydriatic drug (eg, homatropine 2% or 5% drops or cyclopentolate 0.5% or 1.0% drops, either drug given 2 to 4 times/day depending on severity). Antimicrobial drugs are used to treat infectious uveitis.

Particularly severe or chronic cases may require systemic corticosteroids or systemic noncorticosteroid immunosuppressive drugs. For example,

  • Prednisone 1 mg/kg orally once/day

  • Systemic noncorticosteroid immunosuppressive drugs (eg, methotrexate 15 to 25 mg orally once/week; mycophenolate mofetil 500 mg twice daily for 2 weeks, followed by a maintenance dose of 1 to 1.5 g orally twice daily as tolerated; adalimumab, initial dose of 80 mg, followed by 40 mg subcutaneously every 1 to 2 weeks)

  • Infliximab 5 to 10 mg/kg IV every 4 weeks

Additional treatment for severe or chronic cases may require laser phototherapy, cryotherapy applied transsclerally to the retinal periphery, or surgical removal of the vitreous (vitrectomy) (1–3 Treatment references Uveitis is defined as inflammation of the uveal tract—the iris, ciliary body, and choroid. However, the retina and fluid within the anterior chamber and vitreous are often involved as well.... read more Treatment references ).

Treatment references

  • 1. Jaffe GJ, Dick AD, Brézin AP, et al: Adalimumab in patients with active noninfectious uveitis. N Engl J Med 8;375(10):932-43, 2016. doi: 10.1056/NEJMoa1509852

  • 2. Lee J, Koreishi AF, Zumpf KB, et al: Success of weekly adalimumab in refractory ocular inflammatory disease. Ophthalmology S0161-6420(20)30333-X, 2020. doi: 10.1016/j.ophtha.2020.04.009

  • 3. Kruh JN, Yang P, Suelves AM, et al: Infliximab for the treatment of refractory noninfectious uveitis: A study of 88 patients with long-term follow-up. Ophthalmology 121(1):358-364, 2014. doi: 10.1016/j.ophtha.2013.07.019

Key Points

  • Inflammation of the uveal tract (uveitis) can affect the anterior segment (including the iris), intermediate uveal tract (including the vitreous), or posterior uvea (including the choroid, retina, and optic nerve).

  • Most cases are idiopathic, but known causes include infections, trauma, and autoimmune disorders.

  • Findings in acute anterior uveitis include aching eye pain, true photophobia, redness closely surrounding the cornea (ciliary flush), and, on slit-lamp examination, cells and flare.

  • Chronic anterior uveitis may have less dramatic symptoms and present with eye irritation or decreased vision.

  • Intermediate and posterior uveitis tend to cause less pain and eye redness but more floaters and decreased vision.

  • Diagnosis is confirmed by slit-lamp examination and ophthalmoscopic examination (often indirect) after pupillary dilation.

  • Treatment should be managed by an ophthalmologist and often includes corticosteroids and a cycloplegic-mydriatic drug along with treatment of any specific cause.

Drugs Mentioned In This Article

Drug Name Select Trade
AK-Pred, AsmalPred, Econopred, Econopred Plus, Flo-Pred, Hydeltrasol, Inflamase Forte, Inflamase Mild, Millipred , Millipred DP, Millipred DP 12-Day, Millipred DP 6 Day, Ocu-Pred , Ocu-Pred A, Ocu-Pred Forte, Omnipred, Orapred, Orapred ODT, Pediapred, Pred Mild, Predalone, Pred-Forte, Prednoral, Pred-Phosphate , Prelone, Veripred-20
AK-Pentolate , Cyclogyl, Cylate, Ocu-Pentolate
Deltasone, Predone, RAYOS, Sterapred, Sterapred DS
Otrexup, Rasuvo, RediTrex, Rheumatrex, Trexall, Xatmep
CellCept, Myfortic
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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