DÉFI CLINIQUE

Ophthaproblem

Khalid Hasanee, md Sanjay Sharma, MD, MSC, MBA, FRCSC

A 35-year-old woman presents with a 4-day history of sectoral redness in her right eye. She complains only of a mild sensation of a foreign body and has had no associated discharge or change in vision. Her ocular and medical history is unremarkable. She denies any recent cold or infection and has no known allergies.

On examination, her visual acuity is 20/20 in both eyes. All choices below are correct management options, except:

1. Artificial tears
2. Topical steroids
3. Topical nonsteroidal anti-inflammatory drugs
4. Topical gentamicin
5. Oral nonsteroidal anti-inflammatory drugs

Dr Hasanee is a third-year resident in the Department of Ophthalmology at Queen’s University in Kingston, Ont.
Dr Sharma is an Associate Professor in the Department of Ophthalmology and an Assistant Professor in the Department of Epidemiology at Queen’s University.

Answer to Ophthaproblem

Continued from page

4. The incorrect answer is topical gentamicin

This patient has simple episcleritis in her right eye. Episcleritis is inflammatory, so there is no need for antimicrobial therapy.

The episclera is a thin layer of tissue that lies above the sclera and under the conjunctiva. Episcleritis is usually a self-limited, benign, recurrent inflammatory condition affecting the episclera.1,2

Most cases of episcleritis are idiopathic. While the pathophysiology of episcleritis remains unclear,3 sectoral drying of the conjunctiva and underlying episclera is thought to be a factor because episcleritis most commonly occurs in the areas of the eye most frequently exposed (ie, the corners).1,4 Studies have shown, however, that up to 30% of cases could be related to underlying systemic conditions, such as collagen vascular disease (rheumatoid arthritis, systemic lupus erythematosus, polyarteritis nodosa, human leukocyte antigen B27–associated syndromes), infection (bacterial, viral, fungal, parasitic), rosacea, and gout.1-4

Episcleritis is a common condition that most frequently affects adults 20 to 50 years old.4 Classic episcleritis is characterized by transient and recurrent attacks that typically last days to weeks. Most patients with episcleritis complain of sectoral redness associated with a mild sensation of a foreign body and minimal pain. Visual acuity is typically not affected; about 30% of patients have bilateral disease.3,4

Differentiating episcleritis from scleritis

Episcleritis presents similarly to the more serious condition scleritis, which is defined as inflammation of the underlying sclera.5 Both conditions typically have classic sectoral redness while the rest of the eye remains relatively unaffected. Unlike episcleritis, however, scleritis typically presents with more intense “knifelike” pain.6 Patients with scleritis should be referred to an ophthalmologist for ongoing care and a systemic workup.4-6 Other features that can help differentiate episcleritis from scleritis include:

• the pattern of vascular radiation: vessels radiate posteriorly from the limbus in episcleritis; in scleritis, they criss-cross;
• vascular mobility: in episcleritis, vessels are more mobile and can be moved over the deeper sclera with a cotton-tipped applicator; and
• pharmacologic vasoconstriction: in episcleritis, vessels are more likely to blanch when a topical vasoconstrictor (ie, phenylephrine) is used.3,6

Two types of episcleritis

There are two types of episcleritis: simple and nodular.1-6 The more common simple form tends to be mild-to-moderate in severity with recurrent episodes at 1- to 3-month intervals. Most episodes last 1 to 2 weeks and resolve spontaneously.3,4 Patients with prolonged or recurrent episodes might have an underlying systemic condition as the main cause.5 In about 70% of cases, inflammation is localized to one sector of the globe; in about 30%, the entire episclera is involved.5

Nodular episcleritis is less common but usually more severe than simple episcleritis.3,4 It is characterized by a mobile nodule with surrounding and localized episcleral inflammation. Many patients with nodular episcleritis have associated systemic conditions.3

Management

A diagnostic workup for underlying systemic causes is rarely indicated unless patients have a history of many recurrences.3-6 Treatment of episcleritis is typically conservative.1-6 Most clinicians start with artificial tears to treat the underlying dryness that causes secondary irritation. If treatment is unsuccessful, the next step usually involves topical or oral nonsteroidal anti-inflammatory drugs for more severe cases.6 Some cases are persistent and, as a last resort, might require topical steroid therapy under the care of an ophthalmologist.3,5,6 Since episcleritis can recur, steroids should be used with discretion because the potential sight-threatening side effects of steroids include glaucoma and cataracts.3

References

1. Watson PG, Hayreh SS. Scleritis and episcleritis. Br J Ophthalmol 1976;60:163-91.
2. Sainz de la Manza M, Jabbur NS, Foster CS. Severity of scleritis and episcleritis. Ophthalmology 1994;101:389-96.
3. Kanski JJ. Episcleritis. In: Clinical ophthalmology. 4th ed. Woburn, Md: Butterworth-Heinemann; 1999. p. 151-2.
4. Wilhelmus KR, Huang AJN, Hwang DG, Parrish CM. Episcleritis. External disease and cornea. American Academy of Ophthalmology basic and clinical science course 2001. Sect 8. San Francisco, Calif: American Academy of Ophthalmology; 2001. p. 217-8.
5. Roy H. Episcleritis. Omaha, Neb: eMedicine.com Inc; 2001 Available at: www.eMedicine.com. Accessed 2003 June 11.
6. Rhee DJ, Pyfer MF. The Wills eye manual. 3rd ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 1999. p. 133-4.