Uveitis (pronounced you-vee-EYE-tis) is inflammation of the uvea — the middle layer of the eye that consists of the iris, ciliary body and choroid.
Uveitis can have many causes, including eye injury and inflammatory diseases. Exposure to toxic chemicals such as pesticides and acids used in manufacturing processes also can cause uveitis.
The type of uveitis you have is classified by where inflammation occurs in the uvea:
- Anterior uveitis is inflammation of the iris (iritis) or the iris and ciliary body.
- Intermediate uveitis is inflammation of the ciliary body.
- Posterior uveitis is inflammation of the choroid.
- Diffuse uveitis (also called panuveitis) is inflammation of all areas of the uvea.
Many cases of uveitis are chronic, and they can produce numerous possible complications, including clouding of the cornea, cataracts, elevated eye pressure (IOP), glaucoma, swelling of the retina or retinal detachment. These complications can result in permanent vision loss.
Uveitis occurs most frequently in people ages 20 to 50. A California study estimated that more than 280,000 people in the United States are affected by uveitis each year, which is almost three times greater than previously thought.
The study, based on medical records from six northern California communities, also estimated that uveitis is the reason for 30,000 new cases of blindness a year and up to 10 per cent of all cases of blindness.
Anterior uveitis is the most common form, with an annual incidence of about 8 to 15 cases per 100,000 people. This type of uveitis affects men and women equally.
Symptoms of Uveitis
About half of all uveitis cases — with most occurring in the anterior uvea — don’t have an obvious cause. Symptoms of anterior uveitis include light sensitivity, decreased visual acuity, eye pain and red eyes.
Intermediate and posterior uveitis usually are painless. Symptoms of these types of uveitis include blurred vision and floaters, typically in both eyes. Most people who develop intermediate uveitis are in their teens, 20s or 30s.
Diffuse uveitis has a combination of symptoms of all types of uveitis.
What Causes Uveitis?
Uveitis has dozens of causes, including viral, fungal and bacterial infections. But, in many cases, the cause is unknown.
Eye care practitioners sometimes can identify the cause if there has been trauma to the eye, such as from surgery or a blow, or if you have an infectious or immunological systemic disorder.
Some of the many different systemic disorders that can cause uveitis to include:
- acute posterior multifocal placoid pigment epitheliopathy
- ankylosing spondylitis
- Behcet’s disease
- birdshot retinochoroidopathy
- brucellosis
- herpes simplex
- herpes zoster
- inflammatory bowel disease
- juvenile rheumatoid arthritis
- Kawasaki’s disease
- leptospirosis
- Lyme disease
- multiple sclerosis
- presumed ocular histoplasmosis syndrome
- psoriatic arthritis
- Reiter’s syndrome
- sarcoidosis
- syphilis
- systemic lupus erythematosus
- toxocariasis
- toxoplasmosis
- tuberculosis
- Vogt-Koyanagi-Harada syndrome
Also, research published in the journal Ophthalmology shows smoking is a risk factor for uveitis. “Cigarette smoke includes compounds that stimulate inflammation within the blood vessels, and this may contribute to immune system disruption and uveitis,” said University of California San Francisco (UCSF) researcher and ophthalmologist Dr Nisha Acharya, one of the study authors.
Uveitis and Iritis Treatment
If your eye doctor determines you have uveitis, he or she will likely prescribe a steroid to reduce the inflammation in your eye. Whether the steroid is administered as an eye drop, pill or injection depends on the type of uveitis you have. Because iritis affects the front of the eye, it’s usually treated with eye drops.
Posterior uveitis usually requires tablets or injections. Depending on your symptoms, any of these treatments might be used for intermediate uveitis.
Steroids and other immunosuppressants can produce many serious side effects, such as kidney damage, high blood sugar, high blood pressure, osteoporosis and glaucoma.
This is especially true of steroids in pill form because the dose must be relatively high in order for enough of the drug to find its way to the back of the eye. So it is important to follow your doctor’s dosage instructions carefully and to keep visiting him or her regularly to monitor the progress of the treatment.
Retisert (Bausch+Lomb) is the first surgical implant to gain FDA approval for use in the treatment of chronic, non-infectious posterior uveitis in the United States.
Approved in 2005, Retisert is a tiny drug reservoir that is implanted in the back of the eye and delivers sustained amounts of an anti-inflammatory corticosteroid medication called fluocinolone acetonide to the uvea for about 30 months.
During FDA clinical trials, the recurrence of uveitis fell from 40-54 percent to 7-14 percent following Retisert implantation. The most common side effects noted during those studies were cataract progression, increased intraocular pressure, procedural complications and eye pain.
In a later study, researchers found that surgical implantation of the Retisert device was equally effective as systemic corticosteroid medications for the treatment of non-infectious intermediate, posterior and diffuse uveitis over a period of 24 months.
Ozurdex (Allergan) is another long-acting corticosteroid drug implant approved for the treatment of non-infectious uveitis affecting the back segment of the eye. Ozurdex implants contain the steroid medication dexamethasone and are biodegradable.
In addition to uveitis treatment, Ozurdex implants also are FDA-approved for the treatment of macular edema following retinal vein occlusion and for treatment for diabetic macular edema in adult patients who are pseudophakic or who are scheduled for cataract surgery.
If you have anterior uveitis, your doctor likely will prescribe, in addition to steroids, pupil-dilating eye drops to reduce pain. You also may need eye drops to lower your intraocular pressure if you develop high eye pressure due to uveitis.
If you have a known systemic condition that may be contributing to your uveitis, your doctor will treat that as well.
Allergan receives FDA approval for Ozurdex (dexamethasone intravitreal implant) 0.7 mg as a treatment option for use in certain patients with diabetic macular edema. Press release issued by Allergan in June 2014.
Randomized comparison of systemic anti-inflammatory therapy versus fluocinolone acetonide implant for intermediate, posterior and panuveitis: the Multicenter Uveitis Steroid Treatment Trial. Ophthalmology. August 2011.
Dexamethasone intravitreal implant for noninfectious intermediate or posterior uveitis. Archives of Ophthalmology. January 2011.
Allergan receives FDA approval for Ozurdex as a treatment option for non-infectious uveitis affecting the posterior segment of the eye. Press release issued by Allergan in September 2010.
Cigarette smoking is a risk factor for uveitis. Ophthalmology. March 2010.
Idiopathic and other anterior uveitis syndromes. Ophthalmology, 3rd ed. 2008.
Incidence and prevalence of uveitis in Northern California: the Northern California Epidemiology of Uveitis Study. Ophthalmology. March 2004.