What is episcleritis?

What is Episcleritis?

Episcleritis is a benign, self-limited inflammation of the episclera—the thin, loose, highly vascular connective tissue layer between the conjunctiva and sclera—that presents with eye redness, mild discomfort, and typically resolves without vision loss. 1, 2

Clinical Presentation

Episcleritis presents with characteristic features that distinguish it from more serious ocular conditions:

• Relatively painless or mild discomfort with hyperemic (red) sclera and conjunctiva, often accompanied by itching and burning sensations 1
• No visual changes or blurred vision—this is a critical distinguishing feature from scleritis or uveitis 1
• Absence of moderate-to-severe eye pain, photophobia, or diminished vision—when these symptoms are present, you must consider scleritis or uveitis instead 1
• Acute onset of redness, lacrimation (tearing), and mild photophobia may occur 2

Classification and Natural History

• Episcleritis is classified into simple and nodular subtypes 2
• The nodular type tends to be more recurrent and slightly more painful than simple episcleritis 2
• Most attacks resolve spontaneously within 1-3 months without treatment 2
• Incidence is less than 1 per 1,000 people, more common in women and those aged 40-50 years 2

Associated Conditions

• Most cases are idiopathic (no identifiable cause) 2
• Can occur as an extra-intestinal manifestation of inflammatory bowel disease (IBD), where it tends to reflect active bowel disease 1
• May be associated with systemic rheumatological diseases in some cases, though less commonly than scleritis 2, 3

Critical Differentiation from Serious Conditions

You must differentiate episcleritis from scleritis and uveitis, as these require urgent ophthalmologic referral and aggressive systemic treatment:

• Scleritis presents with severe pain, "cloudy" or discolored appearance of the sclera, and potential visual changes—this is a sight-threatening emergency 4, 5
• Uveitis presents with the classic triad of eye pain, blurred vision, and photophobia, plus headache 6
• The presence of visual disturbance, photophobia, or moderate-to-severe pain should immediately prompt ophthalmologic referral to rule out these more serious conditions 1, 6

When to Refer

• Simple episcleritis does not require referral to an ophthalmologist if you can confidently differentiate it from scleritis and uveitis based on the absence of severe pain, photophobia, blurred vision, and diminished vision 1
• When differentiation is uncertain, or if any sight-threatening features are present, immediate ophthalmologic evaluation is mandatory 1
• Even for confirmed episcleritis, ophthalmology consultation is recommended to definitively rule out scleritis 2

Treatment Approach

Episcleritis is benign and often self-resolves, requiring only symptomatic management:

• First-line symptomatic treatment: Cold compresses and artificial tears provide relief 2
• For persistent symptoms: Topical NSAIDs or topical corticosteroids can be used 1, 2
• Systemic NSAIDs may be used for symptomatic relief in cases requiring more than topical therapy 1, 7
• Only 16.7% of episcleritis patients require more than topical corticosteroids, and when they do, oral NSAIDs are typically sufficient 7
• Systemic steroids are rarely necessary and should prompt reconsideration of the diagnosis 2
• Treatment of underlying IBD (when present) often leads to resolution of episcleritis 1

Key Clinical Pitfalls to Avoid

• Do not miss scleritis: Severe pain should immediately raise concern for scleritis, which requires urgent systemic treatment to prevent vision loss 4, 5
• Do not delay ophthalmologic referral when uncertain: Scleritis can progress rapidly to permanent visual damage 4
• Do not confuse with uveitis: The absence of photophobia, blurred vision, and eye pain helps distinguish episcleritis from uveitis 1, 6
• Ocular complications occur in only 13.5% of episcleritis patients compared to 58.8% in scleritis patients, and no episcleritis patients experience decreased visual acuity 7