Episcleritis: Symptoms, Types, Causes and Treatment

Episcleritis is a relatively common, usually benign inflammation of the episclera—the thin, vascularized connective tissue layer between the conjunctiva and sclera of the eye. While it often resolves without complications, its appearance can be alarming and may sometimes indicate underlying health concerns. Understanding its symptoms, various types, causes, and modern treatment options is essential for both patients and healthcare providers. This article provides a comprehensive, evidence-based exploration of episcleritis, drawing on current clinical research and guidelines.

Symptoms of Episcleritis

When episcleritis occurs, it typically announces itself with a strikingly red eye and mild discomfort. While the redness may be concerning, the condition is frequently less severe than it appears. Recognizing the key symptoms is crucial to distinguish episcleritis from more serious ocular inflammatory diseases.

Symptom	Description	Severity	Source(s)
Redness	Acute onset, localized	Mild-Moderate	3, 4, 2
Discomfort	Mild pain or irritation	Mild	4, 3
Photophobia	Sensitivity to light	Mild	3, 2
Tearing	Watery eyes (epiphora)	Mild	2, 3
Foreign Body Sensation	Feels like something in the eye	Mild	2
Visual Acuity	Usually unaffected	None	2, 3, 10

Table 1: Key Symptoms

Common Symptoms and Their Patterns

The hallmark of episcleritis is a sudden-onset redness in one or both eyes, often described as a "salmon pink" or bright red hue. This redness is due to inflammation of the superficial episcleral vessels, which can be distinguished from the deeper, less mobile vessels of scleritis 8.

• Redness: The redness is often localized to a sector of the eye, especially in the nodular type, or may be more diffuse in simple episcleritis. The intensity can range from mild to vivid.
• Discomfort: While some patients describe a gritty, irritating sensation, severe pain is rare. If significant pain is present, clinicians should consider scleritis instead 3.
• Photophobia and Tearing: Mild sensitivity to light and increased tearing are frequently reported but are not universal 2, 3.
• Foreign Body Sensation: Some patients feel as though there is something in their eye, even though nothing is present 2.
• Visual Acuity: Importantly, vision is almost always preserved. Any decrease in vision should prompt evaluation for more serious conditions 3, 10.

Signs That Warrant Further Evaluation

• Severe Pain: Suggests scleritis rather than episcleritis.
• Visual Loss: Not typical; if present, investigate for complications or alternative diagnoses.
• Recurrent Episodes: May indicate an underlying systemic disease 6, 7.

Types of Episcleritis

Episcleritis is not a single uniform disease but includes two distinct clinical subtypes. Recognizing these types helps guide prognosis, management, and the search for underlying causes.

Type	Features	Recurrence	Source(s)
Simple	Diffuse redness, mild discomfort	Common	3, 5, 13
Nodular	Localized, raised nodule with redness	More frequent and persistent	3, 5, 2, 13

Table 2: Main Types of Episcleritis

Simple Episcleritis

Simple episcleritis is the most common form, accounting for the majority of cases 5. It is characterized by:

• Diffuse or sectoral redness without raised nodules.
• Mild discomfort or irritation.
• Self-limited course with episodes lasting 1–3 months.
• Frequent recurrence but generally benign 3, 5, 13.

This type can occur in both adults and children but is more common in middle-aged women 3, 5, 9.

Nodular Episcleritis

Nodular episcleritis is less common but tends to be more persistent and recurrent 3, 5, 13. It has the following features:

• Localized, raised nodule: Typically at the inferotemporal sector of the eye 2.
• Surrounding redness: With a halo of injected vessels.
• Greater discomfort: Can be more tender than simple episcleritis, but still less painful than scleritis.
• Potential association with systemic disease: Slightly higher than in simple episcleritis 6, 7.

Nodular episcleritis has been described in association with infections (e.g., herpes zoster) and autoimmune conditions. It is generally benign and does not progress to scleritis, except rarely in cases related to herpes zoster 5, 13.

Episcleritis in Children

While rare, episcleritis does occur in children and tends to be simple rather than nodular. In older children, it is more frequently associated with underlying rheumatologic diseases 9.

Causes of Episcleritis

Episcleritis is often idiopathic, meaning no specific cause can be identified. However, a significant proportion of cases are linked to systemic conditions, allergic responses, vascular diseases, or infections. Understanding these associations is vital for proper diagnosis and management.

Cause Type	Example Conditions	Frequency	Source(s)
Idiopathic	None identifiable	Most cases	3, 5
Autoimmune	Rheumatoid arthritis, lupus, vasculitis	Up to 30%	7, 6, 9, 1
Allergic	Hypersensitivity reactions	Less common	4
Infectious	Herpes zoster, COVID-19, hepatitis C, others	Rare	2, 4, 13
Vascular	Vasculitis, cryoglobulinemia	Less common	4, 2

Table 3: Main Causes of Episcleritis

Idiopathic Cases

The majority of episcleritis cases arise without a clearly identifiable cause. These idiopathic cases are typically self-limited and recur intermittently 3, 5.

Autoimmune and Rheumatologic Disease

Autoimmune conditions are a well-recognized cause of episcleritis:

• Rheumatoid arthritis: Frequently associated, especially in older patients 1, 7.
• Systemic lupus erythematosus (SLE), spondyloarthropathies, vasculitides: Documented in both adults and children 7, 9.
• Polyarteritis nodosa, inflammatory bowel disease: Occasionally linked 9.

Approximately 30% of patients with episcleritis or scleritis have a systemic autoimmune or rheumatologic disease 6, 7, 9. In children, this proportion may be even higher in those older than five years 9.

Allergic and Hypersensitivity Reactions

Allergic responses can trigger episcleritis, although they are less common than autoimmune causes. These cases may be associated with environmental allergens or hypersensitivity to medications 4.

Infectious Agents

A small number of cases are linked to infections:

• Herpes zoster: Can cause nodular episcleritis and may progress to scleritis 13.
• Viral infections: Recent case reports have linked COVID-19 and hepatitis C to episcleritis, likely through immune-mediated vascular mechanisms 2, 4.
• Other infectious agents: Syphilis, tuberculosis, and even some bacterial infections, though these are rare 13.

Vascular and Immune Complex Disorders

Vascular diseases and disorders related to circulating immune complexes can cause episcleral inflammation:

• Cryoglobulinemia: Secondary to hepatitis C or autoimmune disease 2, 4.
• Vasculitis: Including ANCA-associated vasculitis 7.

Treatment of Episcleritis

The management of episcleritis is generally straightforward, focusing on symptom relief and addressing any underlying systemic disease. Most cases resolve without complications, but treatment may be escalated for persistent or severe cases.

Treatment	Indication	Effectiveness	Source(s)
Artificial tears	Symptomatic relief	High	2, 3
Cold compresses	Mild cases, comfort	High	3
Topical NSAIDs	Persistent or moderate symptoms	Moderate	3
Topical steroids	Unresponsive cases	High	2, 3, 12
Systemic NSAIDs	Severe or recurrent cases	High	10, 13
Systemic steroids	Rare, for resistant cases	High	1, 3, 10
Immunosuppressants	Underlying autoimmune disease	High (for underlying disease)	3, 10

Table 4: Treatment Modalities for Episcleritis

Supportive and Symptomatic Care

For most cases, simple supportive measures are sufficient:

• Artificial tears: Soothe irritation and provide comfort 2, 3.
• Cold compresses: Reduce redness and discomfort 3.
• Observation: Many cases resolve spontaneously within several weeks 3, 5.

Anti-inflammatory Medications

• Topical NSAIDs: Used for persistent discomfort; offer mild anti-inflammatory effects 3.
• Topical corticosteroids: Indicated if symptoms do not improve with supportive care or in nodular episcleritis. Low- to medium-potency steroids such as fluorometholone, clobetasone butyrate, or betamethasone phosphate have demonstrated efficacy 2, 12.
• Systemic NSAIDs: Used in rare, severe, or recurrent cases, or when topical therapy fails 10, 13.
• Systemic corticosteroids: Reserved for refractory cases or when there is an associated systemic disease requiring control 1, 3, 10.

Treating Underlying Conditions

If episcleritis is associated with a systemic disease:

• Immunosuppressive therapy: Medications such as methotrexate, azathioprine, or biologics may be needed to control the underlying autoimmune process 3, 10, 7.
• Antiviral therapy: For herpes zoster or other viral causes, specific antiviral treatment may be indicated 13.

Prognosis and Complications

Episcleritis is typically benign, with rare complications. Ocular complications (such as anterior uveitis, glaucoma, or cataract) occur in a small percentage of cases—much less frequently than in scleritis 6, 10. Visual acuity is usually unaffected 10. Recurrences are common, especially in nodular episcleritis or when associated with systemic disease.

Conclusion

Episcleritis is a common, usually benign ocular inflammatory condition that can be distressing but is rarely dangerous. Its recognition, differentiation from more serious conditions like scleritis, and the identification of any underlying systemic disease are crucial for optimal care.

Key Points Covered:

• Symptoms include redness, mild discomfort, tearing, and photophobia, with vision usually unaffected.
• Types are simple (diffuse redness) and nodular (localized, raised nodule), with nodular types being more recurrent.
• Causes are most often idiopathic, but up to 30% are linked to systemic autoimmune, allergic, infectious, or vascular diseases.
• Treatment is usually supportive (artificial tears, cold compresses), with topical steroids or systemic therapy reserved for persistent, recurrent, or severe cases, or when associated with systemic disease.

If you or someone you know experiences recurrent or severe eye redness, especially with pain or vision changes, prompt medical evaluation is advised to rule out more serious conditions or underlying systemic illnesses.