Scleritis

The dermatitis manifests itself through eye pain as well as discoloration and nodules in the eye. Doctors can usually recognize scleritis visually. Treatment always depends on whether an underlying disease is present. The extent and form of the scleritis also play a role in the treatment.

What is scleritis?

Scleritis is an inflammation of the sclera in the eye. This layer is also called the sclera. It corresponds to the part of the eye that people perceive as “white”. Together with the cornea, the sclera forms the outer skin of the eye. And together with the vitreous body, it gives the eye shape and stability.

Scleritis usually develops in connection with rheumatic diseases. These are autoimmune diseases in which the immune system mistakenly attacks the body’s own structures – these attacks can also affect the sclera in the eye. Sometimes infectious diseases are also involved in the inflammation, for example herpes zoster. Inflammation of the sclera can affect one or both eyes.

Ophthalmologists distinguish between different forms of scleritis – depending on the location and form of the inflammation of the sclera. For example, there is anterior (most common) and posterior scleritis. A distinction is also made between diffuse and nodular scleritis. Classification into necrotizing (with tissue death) and non-necrotizing disease is also extremely important for appropriate treatment.

The inflammation of the dermis becomes noticeable through pain in the eye. Later, red-bluish spots and sometimes nodular yellow protrusions appear in the whites of the eyes. Then the dermatitis is also visually recognizable. Visual acuity can also decrease. Doctors usually treat scleritis with medication that has a pain-relieving and anti-inflammatory effect. Examples are non-steroidal anti-inflammatory drugs (NSAIDs) and cortisone.

Scleritis often takes a chronic course and can be a very protracted affair for those affected. Some develop permanent damage to the eye – in the worst case, those affected can even lose their eye. However, this happens very rarely.

Scleritis – frequency and age

There are no precise figures on the incidence of scleritis, but it is comparatively rare. Experts estimate that around 6 in every 100,000 inhabitants suffer from the disease. Around 40 to 50 percent of patients with dermatitis also suffer from another (systemic) underlying disease. These include rheumatic diseases in particular. Infections and other underlying diseases are less frequently to blame for scleritis.

The eye disease occurs predominantly in the 40th and 60th decade of life. Women contract the disease slightly more often than men.

Scleritis: causes often lie in another disease

The causes of scleritis cannot always be identified and often remain unclear. However, it is known that dermatitis is associated with another underlying disease in up to 50 percent of patients. This is often a rheumatic disease, for example:

• Rheumatoid arthritis
• Granulomatosis with polyangiitis (formerly Wegener’s disease)
• Systemic Lupus Erythematosus (SLE)
• Polychondritis
• Polymyositis (belongs to the collagenoses)
• Gout

Many of these rheumatic diseases are autoimmune diseases, in which the immune system mistakenly attacks the body’s own structures. These can be the muscles, bones and joints, but also the eye tissue – as in the case of scleritis.

Other causes of scleritis

• Chronic inflammatory bowel diseases such as Crohn’s disease and ulcerative colitis can also be associated with scleritis.
• In addition, an existing inflammation of the cornea – keratitis – can spread to the sclera and cause scleritis.
• Rarely (approx. five percent of cases), infections are the cause of scleritis. For example, dermatitis can occur in the context of tuberculosis, syphilis, herpes simplex or herpes zoster(shingles). Bacteria and viruses are the culprits here.
• Finally, the causes of scleritis include injuries (trauma) and medical procedures performed on the eye. These include surgical measures such as an operation for strabismus or wing fur surgery (removal of a pterygium), but in the latter case usually in connection with cytotoxins occasionally used during the operation.

Symptoms: Scleritis causes eye pain

The symptoms of scleritis often begin in one eye. In around half of patients, the sclera also becomes inflamed in the other eye as the disease progresses.

The following symptoms indicate scleritis:

• Eye pain – many describe it as “piercing”, especially at night it robs them of sleep
• Reddening of the eyes – the inflammation causes the blood vessels to fill up more
• Increased sensitivity to light
• The eye reacts sensitively to touch and pressure
• Increased lacrimation
• bluish discoloration of the dermis
• Nodular, yellow protrusions – they cannot be moved
• Decreasing visual acuity

Always consult your ophthalmologist promptly if you have such complaints. He or she will find out whether scleritis could be the cause of the symptoms.

Scleritis: Diagnosis with us

In around 80 percent of scleritis patients, an underlying disease has been known for some time. First and foremost is rheumatoid arthritis. In around ten percent of patients, scleritis is the first indication of a previously unknown systemic disease.

The diagnosis of scleritis begins with a discussion between the doctor and the patient about their medical history (anamnesis). The doctor will ask you a few questions that will allow initial conclusions to be drawn about the cause of the symptoms. These include, for example:

• What are your symptoms?
• When did you first notice them?
• How intense are the complaints?
• Have the symptoms improved again in the meantime or have they increased continuously?
• Do you have any known underlying illnesses, e.g. rheumatic diseases, chronic inflammatory bowel disease or infections?
• Have you recently suffered an eye injury?
• Have you undergone an eye operation?

The ophthalmologist then examines the appearance of both eyes. He or she looks for changes such as redness of the eye, red-bluish discoloration or nodules in the white of the eye.

This is usually followed by an eye examination with a slit lamp. This is a type of microscope with a light source that the ophthalmologist can use to magnify the eye. This allows him to see the condition of the structures of the eye and whether there are any changes.

Sometimes additional imaging procedures are used to assess the posterior regions of the eye. These include, for example, ultrasound examinations (sonography) and computer tomography (CT).

Forms of scleritis: classification

Doctors can classify scleritis into different forms on the basis of the examination results. The decisive factor is which part of the dermis is inflamed and what characteristics and appearance the tissue has (classification according to Watson and Hayreh). Around 90 percent of all dermatitis affects the anterior segment of the eye (anterior forms).

• Anterior diffuse scleritis (40 percent) – the foci of inflammation are not localized but scattered
• Anterior nodular scleritis (44 percent) – small nodules form
• Necrotizing scleritis – the tissue is locally destroyed. This form can occur with inflammation (approx. 10 percent) or without inflammation (approx. 4 percent). The rare Scleromalacia perforans is non-inflammatory. The typical eye pain does not occur here. It often affects women with rheumatoid arthritis.
• Posterior scleritis (approx. 2 percent) – the posterior segment of the eye is inflamed

There is also superficial scleritis (episcleritis), in which the inflammation only affects the connective tissue between the sclera and conjunctiva.

Scleritis: prevention, early detection, prognosis

You cannot really prevent scleritis. Dermatitis often occurs in the context of certain underlying diseases, such as rheumatoid arthritis. And you can hardly protect yourself against these diseases.

If you are known to have such a condition, you should always have it adequately treated. Scleritis can occur in connection with an inadequately treated underlying disease. It is also best to have your eyes checked regularly by an ophthalmologist. Changes can thus be recognized more quickly. Special measures for the early detection of scleritis in the ophthalmologist’s practice are also not known.

The general advice is therefore: always consult an ophthalmologist if you notice any changes to your eyes or vision problems.

Course and prognosis of scleritis

The course and prognosis of scleritis depend on its extent and form. They cannot be generally predicted. However, there is a chance that the dermatitis will heal without consequences. Sometimes, however, vision deteriorates permanently.

Here are some facts:

• Even at the beginning of the disease, inflammation occurs in both eyes in around 25 percent of patients.
• In a further 50 percent, the second eye is only affected later in the course of the disease.
• Around 70 percent of patients experience relapses (recurrences) – the scleritis then usually returns within three to six years. Doctors speak of a chronic relapsing course. These patients need long-term treatment and care.
• If an infection is the cause of the scleritis, the prognosis is less favorable. Some patients even lose their eyes.

Scleritis: treatment to reduce inflammation

The treatment of scleritis is aimed at slowing down the inflammatory processes in the eye and alleviating the symptoms. If an underlying disease is known, such as rheumatoid arthritis, doctors will first treat this sufficiently. The same applies if there is an underlying chronic inflammatory bowel disease or infection. The extent and location of the scleritis also play a role in the choice of therapy.