Uveitis

What is Uveitis?

Uveitis is an inflammation of the the uvea, the layer between the sclera and the retina in the eye and it includes the iris, ciliary body, and the choroid.

What are the causes?

Uveitis is an inflammation affecting the uvea. The uvea provides most of the blood supply to the retina. Causes of uveitis can include autoimmune disorders, infection, or exposure to toxins. However in many cases, the cause remains unknown.

The most common form of uveitis is anterior uveitis, which involves inflammation in the front part of the eye, which is usually confined to the iris. This condition is often called iritis. The inflammation may be associated with autoimmune diseases such as rheumatoid arthritis or ankylosing spondylitis, but most cases occur in healthy people. The disorder may affect only one eye and is common in young and middle-aged people.

Pars planitis is inflammation of the pars plana, a narrow area between the iris and the choroid. Pars planitis usually occurs in young men and is not associated with any other disease, and is usually mild. Posterior uveitis affects the back portion of the uveal tract and involves primarily the choroid. This is called choroiditis. If the adjacent retina is also involved it is called chorioretinitis. Posterior uveitis may follow a systemic infection or occur in association with an autoimmune disease. The inflammation causes spotty areas of scarring on the choroid and retina that correspond to areas with vision loss. The degree of vision loss depends on the amount and location of scarring. If the central part of the retina, called the macula is involved, central vision becomes impaired. Uveitis, affecting one or both eyes, can also be associated with any of the following:

• Tuberculosis
  
• Toxoplasmosis
  
• Sarcoidosis
  
• Syphilis
  
• AIDS
  
• CMV infection
  
• Ulcerative colitis
  
• Rheumatoid arthritis
  
• Herpes zoster infection
  
• Ankylosing spondylitis
  
• Behcet's syndrome
  
• Psoriasis
  
• Reiter's syndrome

What are the symptoms?

The symptoms are as follows:

• Redness of the eye
  
• Blurred vision
  
• Sensitivity to light
  
• Dark, floating spots in the vision
  
• Eye pain

How is it diagnosed?

A detailed medical history and eye examination should be done. If there is suspicion of an associated systemic disease, a physical examination and laboratory tests may be needed to look for the underlying cause.

What is the treatment?

Iritis is usually mild. Spasm of the pupil constriction muscle causes pain which is relieved by drops to dilate the pupil. Dark glasses may be helpful. Steroid eye drops or ointment may be needed. More severe cases require a search for an underlying cause.

Choroiditis requires determination of the underlying cause, and treatment of the underlying disease. The underlying disease may be serious, and additional specialists in infectious disease or rheumatology may be needed for diseases such as syphilis, tuberculosis, AIDS or sarcoidosis.

Treatment is consistent with treatment for the systemic diseases of toxoplasmosis, tuberculosis, sarcoidosis, and so forth. For infectious diseases, corticosteroids are often used along with antibiotic therapy. For autoimmune diseases, various forms of suppression of the immune system may be required.

What is the prognosis?

In anterior uveitis, most attacks last from a few days to weeks with treatment, but relapses are common. In posterior uveitis, the inflammation may last from months to years and may cause permanent vision damage, even with treatment.

Complications

Uveitis can lead to the following complications:

• Glaucoma
  
• Cataracts
  
• Fluid within the retina
  
• Retinal detachment
  
• Vision loss

Can it be prevented?

Treatment of the causative disorders may help to prevent uveitis for some people with existing systemic diseases.