Introduction
Scleritis is a severe inflammation of the white part of the eye (known as the sclera) which causes a painful red eye. It is a rare condition affecting four in 100,000 people per year. It is slightly more common in women than in men, and affects people aged between 40 and 60 years.
There isn’t always an obvious cause of scleritis, but up to half of all cases are associated with other inflammatory conditions, such as
or .Scleritis of the eye is a serious condition that needs emergency treatment by an eye doctor (ophthalmologist) to stop it from progressing or causing permanent loss of vision.
If you think you may have scleritis, or you are unsure, see your doctor immediately or go to the nearest hospital.
Symptoms
Scleritis can affect one of both eyes. One of the main symptoms of scleritis is pain inside and around the eye. It tends to be very painful and can disturb your sleep or stop you from doing your usual daily activities. You may experience a deep, moderate to severe ache which comes on gradually and gets worse when you move your eye.
Your eye may also feel tender to touch and the pain of scleritis may move from your eye to different parts of your face or head, such as your forehead or jaw.
You may also experience other scleritis symptoms, including:
- a
- sensitivity to light
- watering of the eyes
- blurred vision
- gradual loss of vision
Occasionally, you may experience a headache, fever, or vomiting.
There are two types of scleritis:
- anterior scleritis – where the front of the eye is affected
- posterior scleritis – where the back of the eye is affected
Anterior scleritis
This is the most common type of scleritis, making up over 90% of cases.
There are two main types of anterior scleritis. These are:
- Non-necrotising (no tissue death) – which has 2 subtypes:
- Diffuse anterior (most common)– there is widespread inflammation and redness of the eye
- Necrotising (tissue death) – which also has 2 subtypes:
- With inflammation - this is the most serious type of scleritis, which causes severe pain and often causes permanent damage to the eye
- Without inflammation - this is a rare condition called scleromalacia perforans, which is only seen in people with rheumatoid arthritis and doesn’t tend to cause symptoms
Posterior scleritis
This less common type of anterior scleritis makes up fewer than 10% of cases. As it affects the the back of the eye, your eye may feel painful but look quite normal and not red at all.
Posterior scleritis is associated with severe eye pain and can lead to permanent loss of vision.
Causes
In many cases of scleritis, there is no specific cause.
However, up to 50% of people with the condition have one or more inflammatory diseases or go on to develop them. These include:
- diseases involving blood vessel inflammation such as polyarteritis nodosa and
Other causes of scleritis include eye damage, such as an infection, traumatic injury, or surgery.
Diagnosis
Your doctor may suspect you have scleritis after asking you questions about your symptoms, eye health, general health, medical history, family history of diseases, and other questions about your health and lifestyle. Your doctor may also examine your eyes.
Because scleritis must be treated urgently to prevent loss of vision, your doctor is likely to refer you as an emergency to an eye specialist (ophthalmologist), if they suspect scleritis.
Your ophthalmologist may examine your eyes in further detail by looking at the back of the eye using a slit lamp (a microscope using a bright beam of light) and ophthalmoscope (a type of torch with a magnifying lens inside).
Your ophthalmologist may then recommend additional tests to check for signs of inflammation elsewhere in your body, and for conditions associated with scleritis.
These tests may include:
- blood tests
- a urine test
- imaging scans – MRI or CT scan of the face, an eye ultrasound (B-scan ultrasound), and X-rays of other joints
- in rare cases, a biopsy (when a small eye tissue sample is removed and examined under a microscope)
Treatment
Scleritis is a serious condition. You will need to be seen by an ophthalmologist on the same day.
The treatment you receive will depend on the type of scleritis, its severity, and whether there is also an underlying inflammatory condition.
Treatment options may include:
- (NSAIDs), such as ibuprofen
- tablets, if NSAIDs are not effective
- steroid injections into and around your affected eye(s), although this is controversial
- drugs that suppress your immune system, such as methotrexate and cyclophosphamide – if steroids don’t improve the inflammation or the scleritis becomes more severe (they can take several weeks to work)
- drugs that modify the immune system (biological response modifiers), such as infliximab, adalimumab, or rituximab
As scleritis is associated with underlying inflammatory conditions, you may also be referred to a doctor who specialises in managing these types of conditions (a rheumatologist).
Treating scleritis can be a long-term process that may continue for months. In some cases, once the inflammation has been treated, there is a need for additional or ‘maintenance’ treatment to keep the symptoms from returning.
Outlook
The most common type of scleritis (non-necrotising) can be treated without permanent loss of vision in most cases. However, a delay in getting medical help can lead to uveitis, which can threaten vision.
Less common types, such as necrotizing scleritis or posterior scleritis, carry a higher risk of causing loss of vision.
If scleritis is related to an underlying condition like rheumatoid arthritis, your symptoms are likely to progress in the same way as the underlying condition. For example, your eye symptoms may return when you have a flare up of the underlying condition and improve when that condition gets better.
Regardless of the type of scleritis you may have, it can be helpful to share your experience with other people who have also had the condition. Ask your doctor for further information about useful support groups.
Complications
Scleritis can lead to permanent eye damage. Your chance of developing complications depends on the type of scleritis you have, how severe it is, and how quickly you get medical attention.
Some types of scleritis are more likely to affect your vision. These include:
- posterior scleritis – because the nerve that carries visual information from your eye to your brain sits in the posterior part of the sclera
- necrotising scleritis – the most serious (and least common) type of scleritis
The most common complications include:
- thinning of the sclera
- or raised intraocular pressure
Many of these conditions can cause loss of vision and may need surgical treatment.