Scleritis is an inflammation of the sclera, the white outer covering of the eye, which is made of collagen. Blood vessels travel through and on top of the sclera and can be involved in scleritis.
Scleritis can be destructive to the eye, causing intense pain and loss of vision for some people. Although scleritis may be associated with trauma or infection, more than half of scleritis cases are associated with an underlying systemic disease such as rheumatoid arthritis, ankylosing spondylitis, systemic lupus erythematosus, polyarteritis nodosa, granulomatosis with polyangiitis, herpes zoster virus, gout, and syphilis.
Scleritis is thought to be a sign of inflammation that may be present elsewhere in the body. It usually affects women more than men.
Scleritis usually develops in one eye but may affect both eyes together. The main symptoms of scleritis are pain and redness in the white part of the eye that sometimes becomes severe. Other symptoms may include the following:
- Eye pain that involves the head and face
- Light sensitivity
- Blurred or decreased vision
- Eye redness (due to dilated blood vessels that may make the area appear darker red and take on a bluish hue)
There are two main types of scleritis—anterior (the front) and posterior (the back)—depending on what part of the eye is affected.
Anterior scleritis can be further divided into the following three types:
- Diffuse scleritis: The most common type of scleritis, it involves the front half of the sclera.
- Nodular scleritis: Small, tender nodules form on the sclera, representing generalized inflammation.
- Necrotizing scleritis: Also known as scleromalacia perforans, this type can be very serious and may result in loss of vision. This type is more frequently associated with systemic autoimmune disorders.
Posterior scleritis can be a much more severe form of the disease and is sometimes difficult to diagnose. It is described as a change in the thickness of the posterior aspect of the globe, thickening of the posterior coats of the eye (choroid and sclera), and retrobulbar edema. Posterior scleritis is the rarest form of scleritis, involving the back part of the eye. This type may make the eye more susceptible to inflammation of the eye muscles, retinal detachment, and angle closure glaucoma.
Many causes of scleritis are idiopathic (occurring for an unknown reason). Healthcare providers never find a direct cause. Scleritis seems to be most often associated with inflammation occurring in the body from autoimmune conditions. Rarely, it is caused by infections and trauma.
Healthcare providers diagnose scleritis by evaluating your medical history. You will be given tests to measure your visual acuity and intraocular pressure. Your healthcare provider will examine your eyes by using a slit lamp biomicroscope. Also, your eyes will be dilated to examine the inside of your eyes.
Your healthcare provider may use certain eye drops to help distinguish between scleritis and episcleritis, a condition that may also be associated with autoimmune disorders but involves the tissue and vessels in the tissue between the sclera and the conjunctiva.
If left untreated, scleritis can lead to significant loss of vision. Scleritis is usually treated with oral anti-inflammatory medications, such as ibuprofen or prescription-strength nonsteroidal anti-inflammatory drugs (NSAIDs). Oral steroids are often prescribed, as well as a direct injection of steroids into the tissue itself. Immunosuppressive drugs are sometimes used.
Scleritis does not usually respond well to topical eye drop medication, however, so some healthcare providers prescribe topical steroids and NSAIDs. Note, however, that application of topical corticosteroids may make necrotizing scleritis worse.
Treatment of associated problems with scleritis, such as glaucoma, may also be required. Because many cases of scleritis are associated with an underlying systemic disease, treatment is centered around treating that disease to stop the progression of scleritis.
Because scleritis is a condition that usually develops due to an underlying inflammation in the eye, most healthy individuals do not have to worry about developing scleritis. However, if you suffer from autoimmune disorders, healthcare providers recommend you try the following to avoid scleritis:
- Pay attention to the systemic condition you may have that could predispose you to developing scleritis. Keep your healthcare provider visits and take your medication. Even though you may feel fine, you could have inflammation developing silently.
- Stay out of the wind and air. Although this is more common in episcleritis (an inflammation affecting the episcleral tissue causing red eye), some cases of scleritis have developed from external exposure such as constant wind and sun.
- Eat healthily and take a multivitamin. Medical journals have reported cases of scleritis that were thought to be caused by a lack of certain vitamins, such as vitamin D.