Chapter 19: Scleritis and Episcleritis

PATIENT STORY

A 45-year-old woman presents with 1 day of increasing eye pain, eye redness, and blurred vision. On examination, there is scleral injection and exquisite globe tenderness to palpation (Figure 19-1). Her review of systems is positive for morning stiffness and swelling in both of her hands. The patient was urgently referred to an ophthalmologist who diagnosed her with scleritis. Her visual acuity was reduced minimally. A slit lamp exam revealed injected sclera with a bluish hue in the affected eye and rare anterior chamber cells. The posterior segment was normal.

The ophthalmologist prescribed an oral nonsteroidal anti-inflammatory drug (NSAID), specifically indomethacin, as it effectively crosses the blood-brain barrier and gets good levels in the eye.

Her rheumatoid factor was positive, so she was also referred to a rheumatologist.

INTRODUCTION

Episcleritis and scleritis are inflammations of the deeper layers of the eye, the vascular episclera, and the avascular sclera. Episcleritis presents with segmental eye redness, discomfort but not severe pain, and no vision loss. Scleritis can have overlying episcleritis, but also has a violaceous hue, is usually painful, and may cause vision loss. Scleritis typically has an associated underlying condition (autoimmune or infectious) that should be identified and treated. Scleritis is treated with oral NSAIDs, systemic glucocorticoids, or immunosuppressive medications. Patients with scleritis are often referred to an ophthalmologist, as vision loss is common.

EPIDEMIOLOGY

Scleritis:

• In a community-based population study¹:

  • Incidence: 4.1 cases/100,000 person years

  • More common in women than men (6.4 vs. 2.3/100,000 person years)

  • Median age at diagnosis: 56 years; 50% of cases diagnosed between ages 42 and 60

• In tertiary referral centers²:

  • 35.8% of patients with scleritis had an associated systemic illness, most commonly (24.8%) a connective tissue or vasculitic disease

  • Scleritis was diagnosed before the systemic disease in 38.7% of patients

Episcleritis:

• In a community-based population study¹:

  • Incidence: 21.7 cases/100,000 person years

  • More common in women than men (26.0 vs. 17.7/100,000 person years)

  • Median age at diagnosis: 45; 50% of cases diagnosed between ages 32 and 54

• In tertiary referral centers²:

  • 27.1% of patients with episcleritis had an associated systemic illness, most commonly (15.3%) a connective tissue or vasculitic disease

• Nodular or recurrent episcleritis is more likely to be associated with an underlying systemic condition than is an isolated episode of simple episcleritis.

ETIOLOGY AND PATHOPHYSIOLOGY

• Scleritis and episcleritis are inflammatory conditions causing congestion of the deeper 2 of the 3 vascular layers (conjunctival, ...