Uveitis (Iritis)

Uveitis is inflammation of the uvea — the middle layer of the eye that includes the iris, ciliary body, and choroid. It is a potentially sight-threatening condition that requires prompt diagnosis and treatment. Anterior uveitis (iritis), the most common form, causes eye pain, redness, and light sensitivity and is a true ophthalmic urgency.

Types of Uveitis

Type	Location	Common Causes	Symptoms
Anterior (iritis/iridocyclitis)	Iris and ciliary body	HLA-B27, idiopathic, herpes	Pain, redness, photophobia
Intermediate (pars planitis)	Vitreous and pars plana	Multiple sclerosis, sarcoidosis, idiopathic	Floaters, blurred vision
Posterior (choroiditis/retinitis)	Choroid and retina	Toxoplasmosis, CMV, sarcoidosis	Vision loss, floaters
Panuveitis	All layers	Behçet disease, sarcoidosis, Vogt-Koyanagi-Harada	Combined symptoms

Symptoms

Anterior Uveitis (Most Common)

Intermediate and Posterior Uveitis

• Floaters — often prominent
• Blurred vision — may be painless
• Vision loss — can be gradual or sudden
• May have little or no redness or pain

Causes and Risk Factors

Autoimmune and Inflammatory

• HLA-B27-associated — linked to ankylosing spondylitis, reactive arthritis, inflammatory bowel disease, psoriatic arthritis
• Sarcoidosis — can cause any type of uveitis
• Juvenile idiopathic arthritis (JIA) — important cause in children, often silent (no pain or redness)
• Behçet disease — severe panuveitis with hypopyon
• Vogt-Koyanagi-Harada (VKH) — bilateral panuveitis with neurologic and skin findings
• Multiple sclerosis — associated with intermediate uveitis

Infectious

• Toxoplasmosis — most common infectious cause of posterior uveitis
• Herpes simplex and herpes zoster — anterior uveitis with characteristic findings
• Cytomegalovirus (CMV) — retinitis in immunocompromised patients
• Tuberculosis — granulomatous uveitis
• Syphilis — "the great imitator," can cause any type of uveitis

Idiopathic

About 30-50% of uveitis cases have no identifiable cause despite workup.

Diagnosis

Eye Examination

• Slit-lamp exam — the essential tool; reveals cells and flare (protein) in the anterior chamber, keratic precipitates on the corneal endothelium, and posterior synechiae (iris adhesions to the lens)
• Dilated fundus exam — checks for posterior involvement (vitritis, retinal lesions, macular edema)
• OCT — detects macular edema, a common cause of vision loss in uveitis
• Intraocular pressure measurement — uveitis can cause elevated or low eye pressure

Laboratory Workup

Depending on presentation, may include:

• HLA-B27 testing
• Chest X-ray or CT (sarcoidosis, tuberculosis)
• ACE and lysozyme levels (sarcoidosis)
• Syphilis serology (RPR/VDRL, FTA-ABS)
• TB testing (QuantiFERON or PPD)
• Complete blood count, inflammatory markers
• Additional testing based on clinical suspicion

Treatment

Anterior Uveitis

Topical corticosteroid drops — the mainstay:

• Prednisolone acetate 1% — started frequently (every 1-2 hours) then tapered slowly
• Never stop steroid drops abruptly — rebound inflammation is common
• Typical taper over 4-8 weeks

Cycloplegic drops (atropine, cyclopentolate):

• Dilate the pupil and relax the ciliary muscle
• Relieve pain from ciliary spasm
• Prevent posterior synechiae (iris sticking to the lens)

Intermediate, Posterior, and Chronic Uveitis

Periocular or intravitreal steroid injections:

• For cases not responding to drops or with macular edema
• Triamcinolone, dexamethasone implant (Ozurdex)

Systemic corticosteroids:

• Oral prednisone for severe bilateral or posterior uveitis
• Used as a bridge while steroid-sparing agents take effect

Steroid-sparing immunosuppressive therapy — for chronic or recurrent uveitis:

• Methotrexate
• Mycophenolate mofetil
• Azathioprine
• Biologic agents: adalimumab (Humira — FDA-approved for non-infectious uveitis), infliximab

Treating the Underlying Cause

• Infectious uveitis requires appropriate antimicrobial therapy (not steroids alone)
• Systemic inflammatory diseases may require rheumatologic co-management

Complications

If not adequately treated, uveitis can lead to:

• Cataracts — from chronic inflammation and/or steroid use
• Glaucoma — from inflammation, synechiae, or steroid response
• Cystoid macular edema — fluid in the macula causing vision loss
• Posterior synechiae — iris adhering to the lens, causing irregular pupil
• Band keratopathy — calcium deposits on the cornea
• Hypotony — dangerously low eye pressure in chronic cases
• Permanent vision loss if untreated

When to See a Doctor

Frequently Asked Questions

Is uveitis contagious?

No. Even when uveitis is caused by an infection (like toxoplasmosis), the eye inflammation itself is not contagious.

Will my uveitis keep coming back?

Many patients with anterior uveitis have one or a few episodes that resolve completely. However, some forms are recurrent or chronic. HLA-B27-associated uveitis tends to recur. Your ophthalmologist will discuss long-term management based on your specific situation.

Can uveitis cause blindness?

Untreated or inadequately treated uveitis can lead to permanent vision loss from complications like glaucoma, macular edema, or cataracts. With proper treatment, most patients maintain good vision.

Why do I need blood tests for an eye problem?

Uveitis can be the first sign of a systemic disease (like sarcoidosis, ankylosing spondylitis, or syphilis). Blood tests help identify an underlying cause so it can be treated appropriately and future flare-ups can be prevented.

How long will I need steroid drops?

A typical anterior uveitis episode requires 4-8 weeks of tapered steroid drops. Stopping too quickly causes rebound inflammation. Always follow the taper schedule prescribed by your ophthalmologist — never stop on your own.

Can children get uveitis?

Yes. Juvenile idiopathic arthritis (JIA) is an important cause of uveitis in children. Uniquely, JIA-related uveitis is often "white and quiet" — meaning the eye may not look red or painful — making regular screening essential for children with JIA.

References