Episcleritis

Signs and symptoms

Symptoms of episcleritis typically include painless redness of the eye (mild pain is possible but atypical), and watery eyes. The pain of episcleritis is typically mild, less severe than in scleritis, and may be tender to palpation.

There are two types of episcleritis: the diffuse type, where the redness involves the entire episclera, and the nodular type, where the redness appears more nodular, involving only a small, well-circumscribed area (sectoral). The diffuse type of episcleritis may be less painful than the nodular type. Sometimes, small nodules are present within the episclera, which move slightly over the sclera with gentle pressure.

Discharge is absent with episcleritis, and vision is unaffected. Patients with episcleritis experience far less photophobia than patients with uveitis. whereas scleritis often affects both eyes.

Pathophysiology

Episcleritis is caused by inflammation due to the activation of immune cells, including lymphocytes and macrophages. Several diseases are associated with episcleritis, including systemic vasculitis (polyarteritis nodosa, granulomatosis with polyangiitis, Behçet's disease), connective tissue diseases (rheumatoid arthritis, relapsing polychondritis, systemic lupus erythematosus), psoriatic arthritis, ankylosing spondylitis, Cogan syndrome, rosacea, gout, Rarely, episcleritis may be caused by scleritis. Very rarely, episcleritis is associated with infections, including Lyme disease, tuberculosis, syphilis, and herpes zoster.

The redness in the eye associated with episcleritis is due to engorgement of the large episcleral blood vessels, which run in a radial direction from the limbus. Typically, there is no uveitis, or thickening of the sclera.

Diagnosis

The diagnosis of episcleritis is based upon the history and physical examination. The history should be explored for the presence of the diseases associated with episcleritis, and the symptoms they cause, such as rash, arthritis, venereal disease, and recent viral infection. Episcleritis may be differentiated from scleritis by using phenylephrine or neosynephrine eye drops, which causes blanching of the blood vessels in episcleritis, but not in scleritis. A blue color to the sclera suggests scleritis, rather than episcleritis. After anesthetizing the eye with medication, the conjunctiva may be moved with a cotton swab to observe the location of the enlarged blood vessels. In very rare cases, if episcleritis does not respond to treatment, then a biopsy may be considered, which help provide information regarding any underlying condition (granulomatosis with polyangitis, vasculitis, etc.). However, a biopsy is not routinely necessary in the diagnosis of episcleritis.

Treatment

Often, treatment is not necessary, because episcleritis is a self-limiting condition. Artificial tears may be used to help with irritation and discomfort. More severe cases can be treated with either topical corticosteroids or oral non-steroidal anti-inflammatory drugs.

Ketorolac, a topical NSAID, may be used, but it is not more effective than artificial tears and it causes more side effects.

Prognosis

Episcleritis is a benign, self-limiting condition, meaning patients recover without any treatment. Most cases of episcleritis resolve within 7–10 days. Smoking tobacco delays the response to treatment in patients with episcleritis.

Epidemiology

While episcleritis is a common disease, its exact prevalence and incidence are unknown.

References

References

1. "Episcleritis".
2. Heath, Greg. (10 February 2010). "The episclera, sclera and conjunctiva An overview of relevant ocular anatomy". OT.
3. Goldman, Lee. (2011). "Goldman's Cecil Medicine". Elsevier Saunders.
4. Chumley H. (2009). "The Color Atlas of Family Medicine: Chapter 16. Scleritis and Episcleritis.". McGraw-Hill Education Medical.
5. Kunimoto, Derek. (2004). "The Wills eye manual: office and emergency room diagnosis and treatment of eye disease.". Lippincott Williams & Wilkins.
6. (January 2020). "Episcleritis".
7. Yanoff, Myron. (2008). "Ophthalmology". Mosby.
8. Watson, PG. (March 1976). "Scleritis and episcleritis.". The British Journal of Ophthalmology.
9. Langholz, E.. (March 2010). "Review: Current trends in inflammatory bowel disease: the natural history". Therapeutic Advances in Gastroenterology.
10. "Episcleritis: MedlinePlus Medical Encyclopedia". [[United States National Library of Medicine]].
11. Williams, CP. (July 2005). "A randomised, double-blind trial of topical ketorolac vs artificial tears for the treatment of episcleritis.". Eye.
12. Boonman, Z F H M. (September 2005). "Smoking delays the response to treatment in episcleritis and scleritis". Eye.
13. Levsky M.E.. (2010). "Atlas of emergency medicine: Chapter 2 Ophthalmologic Conditions.". McGraw-Hill Professional.