Iritis
Symptoms
Iritis can occur in one or both eyes. It usually develops suddenly, and can last up to three months.
Signs and symptoms of iritis include:
- Eye redness
- Discomfort or achiness in the affected eye
- Sensitivity to light
- Decreased vision
Iritis that develops suddenly, over hours or days, is known as acute iritis. Symptoms that develop gradually or last longer than three months indicate chronic iritis.
Causes
Often, the cause of iritis can’t be determined. In some cases, iritis can be linked to eye trauma, genetic factors or certain diseases. Causes of iritis include:
- Injury to the eye. Blunt force trauma, a penetrating injury, or a burn from a chemical or fire can cause acute iritis.
Infections. Viral infections on your face, such as cold sores and shingles caused by herpes viruses, can cause iritis.
Infectious diseases from other viruses and bacteria can also be linked to uveitis. For instance, they may include toxoplasmosis, an infection most often caused by a parasite in uncooked food; histoplasmosis, a lung infection that occurs when you inhale spores of fungus; tuberculosis, which happens when bacteria enters the lungs; and syphilis, which is caused by the spread of bacteria through sexual contact.
- Genetic predisposition. People who develop certain autoimmune diseases because of a gene alteration that affects their immune systems might also develop acute iritis. Diseases include a type of arthritis called ankylosing spondylitis, reactive arthritis, inflammatory bowel disease and psoriatic arthritis.
- Behcet’s disease. An uncommon cause of acute iritis in Western countries, this condition is also characterized by joint problems, mouth sores and genital sores.
- Juvenile rheumatoid arthritis. Chronic iritis can develop in children with this condition.
- Sarcoidosis. This autoimmune disease involves the growth of collections of inflammatory cells in areas of your body, including your eyes.
- Certain medications. Some drugs, such as the antibiotic rifabutin (Mycobutin) and the antiviral medication cidofovir, that are used to treat HIV infections can be a rare cause of iritis. Rarely, bisphosphonates, used to treat osteoporosis, can cause uveitis. Stopping these medications usually stops the iritis symptoms.
Uveitis
Symptoms
The signs, symptoms and characteristics of uveitis may include:
- Eye redness
- Eye pain
- Light sensitivity
- Blurred vision
- Dark, floating spots in your field of vision (floaters)
- Decreased vision
Symptoms may occur suddenly and get worse quickly, though in some cases, they develop gradually. They may affect one or both eyes. Occasionally, there are no symptoms, and signs of uveitis are observed on a routine eye exam.
The uvea is the middle layer of tissue in the wall of the eye. It consists of the iris, the ciliary body and the choroid. When you look at your eye in the mirror, you will see the white part of the eye (sclera) and the colored part of the eye (iris).
The iris is located inside the front of the eye. The ciliary body is a structure behind the iris. The choroid is a layer of blood vessels between the retina and the sclera. The retina lines the inside of the back of the eye, like wallpaper. The inside of the back of the eye is filled with a gel-like liquid called vitreous.
The type of uveitis you have depends on which part or parts of the eye are inflamed:
- Anterior uveitis affects the inside of the front of your eye (between the cornea and the iris) and the ciliary body. It is also called iritis and is the most common type of uveitis.
- Intermediate uveitis affects the retina and blood vessels just behind the lens (pars plana) as well as the gel in the center of the eye (vitreous).
- Posterior uveitis affects a layer on the inside of the back of your eye, either the retina or the choroid.
- Panuveitis occurs when all layers of the uvea are inflamed, from the front to the back of your eye.
Causes
In about half of all cases, the specific cause of uveitis isn’t clear, and the disorder may be considered an autoimmune disease that only affects the eye or eyes. If a cause can be determined, it may be one of the following:
- An autoimmune or inflammatory disorder that affects other parts of the body, such as sarcoidosis, ankylosing spondylitis, systemic lupus erythematosus or Crohn’s disease
- An infection, such as cat-scratch disease, herpes zoster, syphilis, toxoplasmosis or tuberculosis
- Medication side effect
- Eye injury or surgery
- Very rarely, a cancer that affects the eye, such as lymphoma