Overview of scleritis
The sclera is the protective outer layer of the eye, which is also the white part of the eye. It’s connected to muscles that help the eye move. About 83 per cent of the eye surface is the sclera.
Scleritis is a disorder in which the sclera becomes severely inflamed and red. It can be very painful. Scleritis is believed to be the result of the body’s immune system overreacting. The type of scleritis you have depends on the location of the inflammation. Most people feel severe pain with the condition, but there are exceptions.
There is not always an obvious reason why it happens, but most of the time, it is caused by an autoimmune disorder (when your body’s defence system attacks its own tissues). Some of those that are related to scleritis include:
- Rheumatoid arthritis
- Sjogren’s syndrome
- Wegener’s granuloma
- Inflammatory bowel disease
It can also be caused by an eye infection, an eye injury, or a fungus or parasite. If left untreated, this can lead to serious problems, such as loss of vision. It can also be related to problems with the blood vessels (known as a vascular disease).
What are the types of scleritis?
Doctors use what’s called the Watson and Hayreh classification to distinguish the different types of scleritis. Classification is based upon whether the disease is affecting the anterior (front) or posterior (back) of the sclera. The anterior forms are most likely to have an underlying illness as part of their cause.
The subtypes of anterior scleritis include:
- Anterior scleritis: the most common form of scleritis
- Nodular anterior scleritis: the second most common form
necrotizing anterior scleritis with inflammation: the most serious form of anterior scleritis
- Necrotizing anterior scleritis without inflammation: the rarest form of anterior scleritis
- Posterior scleritis: more difficult to diagnose and detect because it has variable symptoms, including many that mimic other disorders
What are the symptoms of scleritis?
Each type has similar symptoms and can get worse if the condition is not treated. Severe eye pain that responds poorly to pain relievers is the main symptom. Eye movements are likely to make the pain worse. The pain can spread all over the face, especially on the side of the affected eye. Other symptoms can include:
- Excessive tearing
- Decreased vision
- Blurry vision
- Sensitivity to light or photophobia
- Redness of the sclera or white part of the eye
The symptoms are not as obvious because it does not cause severe pain like other types. Symptoms include:
- Deep-seated headaches
- Pain caused by eye movement
- Eye irritation
- Double vision
Some people experience little to no pain. This may be because they have:
- Milder case
- Scleromalacia perforans, which is a rare complication of advanced rheumatoid arthritis (RA).
- History of using immunosuppressive medications (they prevent activity in the immune system) before symptoms began
Causes of scleritis
This is often related to an autoimmune disease. Sometimes there is no known cause.
- Swelling and stiffness of the joints (arthritis)
- Lupus or another connective tissue disease
- Eye infection
- Inflammatory bowel disease (IBD)
- Sjogren’s syndrome (grounds very dry eyes and other symptoms)
It can be caused by trauma (injury) to the eye. In rare cases, it is caused by a fungus or parasite.
If you develop these, you should be urgently referred to an ophthalmologist (ophthalmologist). Usually, it will be necessary to see you on the same day. Treatment will depend on the type and its severity.
Non-necrotizing types are usually treated with oral NSAIDs. If this is not effective, oral steroids are needed. Some doctors treat with steroid injections into the sclera or around the eye.
If these treatments don’t work, immunosuppressive drugs such as methotrexate and cyclophosphamide can be used. They can take several weeks to work.
Some of the newer “biological agents” like rituximab may also be effective. Sometimes surgery is needed to treat complications of scleritis.
It is treated with oral steroids and immunosuppressants as soon as possible. Scleromalacia perforans does not respond well to treatment. Research continues to find the best way to manage this rare condition.
The diagnosis is made clinically and by a slit lamp examination. Biopsies are necessary to confirm infection. A CT scan or ultrasound may be needed for this.
It may occur at any age. Women are more likely to develop it than men. There’s no specific race or area of the world where this condition is more common.
You have an increased chance of developing scleritis if you have:
- Wegener’s disease (Wegener’s granulomatosis), which is an uncommon disorder that involves inflammation of the blood vessels.
- Rheumatoid arthritis (RA), which is an autoimmune disorder causing inflammation of the joints.
- Inflammatory bowel disease (IBD), which causes digestive symptoms due to inflammation of the bowel.
- Damage to eye tissues from an accident
While it is not possible to prevent scoliosis from occurring in the first place, there are things you can do to prevent scoliosis from progressing. One is to examine your child’s spine regularly, starting when he is a baby. If you have any concerns about what you see, speak with your doctor or other healthcare professional.