Who can get it
Uveitis occurs when the eye becomes inflamed (red and swollen).
Inflammation is the body's response to illness or infection.
Most cases of uveitis are linked to a problem with the immune system (the body's defence against infection and illness).
Rarely, uveitis may occur without the eye becoming red or swollen.
Immune system problems
Uveitis often occurs in people who have an underlying autoimmune condition (where the immune system mistakenly attacks healthy tissue).
Autoimmune conditions known to cause uveitis include:
Infection
Uveitis can also be caused by an infection, such as:
Other causes
Uveitis can also be caused by:
- trauma or injury to the eyes, or eye surgery
- some types of cancers, such as Non-Hodgkin lymphoma, although this is a very rare cause of uveitis
Sometimes, a specific cause of uveitis can't be identified.
Gene HLA-B27
Although uveitis isn't passed down through families, a gene known as HLA-B27 has been linked to an increased risk of developing anterior uveitis (uveitis at the front of the eye).
About half of all people with anterior uveitis have the HLA-B27 gene. The gene has been found in people with certain autoimmune conditions, including ankylosing spondylitis, ulcerative colitis, psoriatic arthritis, Crohn's disease and reactive arthritis.
Treatment
Treatment for uveitis depends on what's causing it and which area of the eye is affected.
Medication is the main treatment, but in rare cases, surgery may be recommended to treat particularly severe uveitis.
Steroid medication
Most cases of uveitis can be treated with steroid medication. A medicine called prednisolone is usually used.
Steroids work by disrupting the normal function of the immune system so it no longer releases the chemicals that cause inflammation.
Steroid medicines come in different forms, and the type used will often depend on the areas of your eye affected by uveitis.
Steroid eyedrops
Steroid eyedrops are usually the first treatment used for uveitis that affects the front of the eye (anterior uveitis) and isn't caused by an infection.
Depending on your symptoms, the recommended dose can range from having to use eyedrops every hour to once every two days.
You may have temporary blurred vision after using the drops. Don't drive or operate machinery until your vision returns to normal.
In some people, steroid eyedrops can increase pressure in the eye. The ophthalmologist will check for this and advise you if this happens.
Don't stop using your eyedrops until your GP or ophthalmologist tells you it's safe to do so, even if your symptoms disappear. Stopping treatment too soon could lead to your symptoms returning. The frequency of drops will usually be slowly reduced over a number of weeks.
Steroid injections
If the middle or back of your eye is affected (intermediate or posterior uveitis), or corticosteroid eyedrops haven't worked, you may need corticosteroid injections.
Local anaesthetic eyedrops are used to numb your eye so you won't feel any pain or discomfort.
You'll usually only require one injection while your symptoms are at their worst.
Steroid injections rarely cause significant side effects, but in some people they can make the pressure in the eye increase. The ophthalmologist will check for this and advise you if this happens.
Steroids tablets or capsules
Steroids tablets or capsules are the strongest form of steroids. They're usually used if steroid eyedrops and injections haven't worked or are unsuitable, or for uveitis affecting the back of the eye.
Steroids tablets can cause a wide range of side effects, so will only be recommended if it's thought there's a risk of permanent damage to your vision.
How long you'll have to take oral steroids for depends on how well you respond to treatment and whether you have an underlying autoimmune condition.
Some people only need a three- to six-week course, while others need to have a course lasting months or possibly years.
Short-term side effects of corticosteroids tablets or capsules can include weight gain, increased appetite, insomnia and mood changes – such as feeling irritable or anxious.
In the long term they can cause osteoporosis, thinning of the skin, and an increased risk of infection.
To minimise any side effects, you'll be prescribed the lowest possible dose to control your symptoms.
Read more about the side effects of steroids.
Don't stop taking corticosteroids until your doctor says it's safe to do so. Suddenly stopping your medication can cause unpleasant withdrawal effects.
When your GP or ophthalmologist thinks you can stop the treatment, they'll advise you about how to gradually reduce the amount of steroids you're taking.
Mydriatic eyedrops
If you have uveitis that affects the front of your eye (anterior uveitis), you may be given mydriatic (or dilating) eyedrops in addition to steroid medication.
These drops enlarge (dilate) your pupils and relieve pain by relaxing the muscles in your eye. They can also reduce your risk of developing glaucoma, which affects vision.
However, mydriatic eyedrops can cause some temporary blurring of your vision and problems focusing your eyes.
Treating infection
If an underlying infection is causing your uveitis, the infection may also need to be treated.
Viruses can be treated with antiviral medication, bacterial infections can be treated with antibiotics, and fungal infections can be treated with antifungal medication.
Immunosuppressants
Immunosuppressant may be recommended if you're among the few people who don't respond to the treatments described above.
Immunosuppressants work by controlling the immune system and disrupting the process of inflammation.
If steroid treatment is causing significant side effects, immunosuppressants can also be used to allow your dose of steroids to be reduced.
Possible side effects of immunosuppressants include:
Taking immunosuppressants will make you more vulnerable to infection, so you should try to avoid close contact with anyone who has a known infection.
Report any symptoms of a potential infection, such as a high temperature, cough, or inflammation in other parts of your body, to your GP. You should also have the annual flu jab.
Immunosuppressants can also affect the functioning of some organs and systems, such as the lungs, liver, kidneys and bone marrow. Blood tests are needed at regular intervals to check these systems remain healthy.
A small number of people with uveitis can benefit from treatment with immunosuppressants known as biologics.
Surgery
Rarely, an operation called a vitrectomy may be needed to treat uveitis. It's usually only recommended if you have repeated or severe uveitis, or if the condition is caused by certain infections.
A vitrectomy involves gently sucking out the vitreous humour (the jelly-like substance that fills the inside of the eye). It can be carried out using either general anaesthetic or local anaesthetic.
During the operation, the fluid inside your eye will be temporarily replaced with either a bubble of air or gas (or a mixture of the two), or a liquid substitute. Eventually, the vitreous humour will naturally replace itself.
Like all operations, a vitrectomy carries a risk of complications. These include needing further surgery and an increased risk of developing cataracts.
Symptom relief
The following measures may help relieve your symptoms:
- wearing dark glasses if your eye becomes sensitive to light
- placing a warm flannel over your eye to soothe it
- taking painkillers, such as ibuprofen, to relieve pain