What is Scleritis?
In This Article
Scleritis is a medical condition where the sclera (the white portion of your eye) is inflamed. It can be acutely inflamed due to a one time insult to the eyes or in can be chronically inflamed due to repetitive exposure to trauma, chemicals or any other irritating substances. It may also be related to a number of systematic diseases such as autoimmune diseases.
The sclera comprises a major portion of the visible eye and is prone to being exposed to a variety of hazards in the environment. One must take great care to avoid these hazards in order to prevent a painful and potentially blinding condition from arising.
What is Anatomy of the eye?
The eye is a delicate sense organ that is comprised of highly specialized tissue dedicated to receiving and processing visual information from the environment. These goes hand in hand with basic survival functions such as seeking food, identifying threats and potential mates.
The eye is covered by a white outer layer that is the sclera. While it’s most obvious function is to cover the eyeball, from an evolutionary standpoint the sclera allows easy identification of where the person is looking at which plays a great role in non-verbal communication.
The sclera provides form and body to the eye and allows it to occupy most of the eye socket. It is also attached to the eye muscles that allow it to move around.
Trauma or any kind of injury to the sclera is made apparent by inflammation and presentation of engorged blood vessels on the sclera. The eye is well protected by the corneal and blink reflex which causes the eye to blink in response to a touch stimuli or a rapidly moving object respectively.
Scleritis can be caused by a variety of trauma or systemic immune diseases that damage the normal tissue of the sclera. At any given point where damage is received, the eye displays the same inflammatory process as the rest of the body.
In the case of scleritis, redness (rubor), swelling (tumor), warm to touch (calor), pain (dolor, and the most significant symptom why the patient seeks treatment) and possibly loss of function, in this case, blindness (functionale laesa).
Trauma is common and injury to the globe of the eye may cause the scleritis to appear anywhere along the exposed sclera. In cases of autoimmune diseases, rheumatoid arthritis, Systemic Lupus Erythematosus and Wegener’s Granulomatosis are implicated. Pain in the affected eye is the hallmark symptom of scleritis.
It is believed that the damage is caused by a hypersensitivity reaction of circulating immune antigen-antibody complex to the scleral tissue (Type II hypersensitivity) and subsequent granuloma formation in the scleral body (Type IV sensitivity). The anterior or posterior chamber of the eye can be affected in scleritis.
If the anterior portion of the sclera is affected, it may be necrotizing (forming dead tissues) with inflammation or without inflammation. The most common clinical forms seen at the outpatient department are diffuse and nodular scleritis. This is an ominous form of the disease which may herald oncoming blindness. The posterior form manifests as flattening of the posterior aspect of the globe as well as retro bulbar (back of the eyeball) edema.
Eventually, as the inflammation continues and damage goes unabated, the affected eye is painful and the vision is gradually lost as the cells responsible for processing light are affected. Rapid diagnosis and immediate treatment of the underlying cause are required to save the eye.
Signs & Symptoms
The following pain descriptions are characteristic of scleritis: The patient needs to seek immediate medical attention if ever they have these signs and symptoms so that prompt treatment may begin to prevent catastrophic vision loss.
- Severe, penetrating pain that radiates to the forehead, brow, jaw, or sinuses
- Awakens the patient during the night
- Exacerbated by touch; extremely tender
- Only temporarily relieved by analgesics
- Red, inflamed or violaceous discoloration of the eye
Treatment & Management
The treatment of scleritis almost always requires systemic therapy. Immunosuppressant or corticosteroids can be used to manage the inflammation while a concurrent antibacterial therapy may be initiated in cases where there is an underlying bacterial infection.
Patients with an associated disease, such as rosacea, gout, atopy, or infection, need disease-specific treatment.
Systemic therapy complements aggressive topical corticosteroid therapy, generally with difluprednate, prednisolone or loteprednol etabonate, thereby reducing the dose requirements for both topical and oral modalities.
This combination therapy mitigates, to some extent, the inherent risks of oral steroids, including hypertension and diabetes, among many others; the risks of GI and renal morbidity caused by oral nonsteroidal anti-inflammatory drugs (NSAIDs); and the risks of elevated IOP and cataractogenesis due to topical steroids.
Diffuse Scleritis or Nodular Scleritis
The initial therapy consists of an NSAID; in case of therapeutic failure, 2 additional successive different NSAIDs should be tried following the first drug. In high-risk patients, consideration is appropriate for gastrointestinal protection with misoprostol or omeprazole.
If NSAIDs are not effective or have untoward complications, oral corticosteroids can be substituted. Remission may be maintained with continued NSAIDs.
Scleritis is a medical emergency that warrants immediate medical attention. More often than not the disease is brought about by an underlying autoimmune reaction that has gone awry.
Steps have to be taken to ensure that the underlying inflammation is resolved and so that proper treatment may begin. If given early treatment the scleritis can resolve without any lasting effects as long as proper management is given through the course of the disease.
- Harrison’s Principles of Internal Medicine 19th edition
- Will’s Eye Manual 3rd edition
- Robbin’s Pathology 9th edition