Scleritis

Overview

Scleritis is a serious inflammatory condition affecting the sclera, the tough, white outer coating of the eye that helps maintain the eye's shape and protects its inner contents. Unlike the more common and milder episcleritis, which affects only the superficial layer, scleritis involves inflammation of the deeper scleral tissues and can threaten vision if left untreated. The condition is characterized by severe eye pain, redness, and potential complications that can lead to permanent vision loss, making prompt diagnosis and treatment essential.

The sclera consists of dense, fibrous connective tissue that provides structural support to the eye. When inflammation affects this tissue, it can cause significant pain due to the rich nerve supply and can lead to thinning or necrosis of the sclera. Scleritis is often associated with systemic autoimmune conditions, with approximately 30-40% of cases linked to underlying diseases such as rheumatoid arthritis, granulomatosis with polyangiitis, or systemic lupus erythematosus. This association makes scleritis not just an eye problem but potentially a manifestation of systemic disease requiring comprehensive evaluation.

Scleritis can be classified into anterior (affecting the front part of the sclera) and posterior (affecting the back part) forms, with anterior scleritis being more common. The condition predominantly affects women more than men and typically occurs in middle-aged adults, though it can affect people of any age. While relatively rare, affecting approximately 4-6 people per 100,000 annually, scleritis is considered an ophthalmologic emergency due to its potential for serious complications including vision loss, perforation of the globe, and secondary glaucoma. Early recognition and aggressive treatment are crucial for preserving vision and preventing long-term complications.

Symptoms

Scleritis presents with distinctive symptoms that often help differentiate it from other eye conditions. The severity and specific symptoms can vary depending on the type and extent of inflammation.

Primary Symptoms

Characteristic Features

• Pain that worsens with eye movement
• Pain that awakens patient from sleep
• Tenderness when touching the eye through closed lid
• Photophobia (light sensitivity)
• Excessive tearing (lacrimation)
• Swelling of the eyelids
• Nodular elevations on the sclera (in nodular scleritis)

Type-Specific Symptoms

Anterior Scleritis

• Diffuse: Widespread inflammation, intense redness
• Nodular: Distinct nodules on sclera, localized pain
• Necrotizing with inflammation: Most severe, extreme pain, scleral thinning
• Necrotizing without inflammation (scleromalacia perforans): Painless, progressive thinning

Posterior Scleritis

• Pain without visible redness
• Vision loss or distortion
• Double vision (diplopia)
• Proptosis (eye bulging)
• Limitation of eye movement
• Retinal detachment symptoms

Associated Symptoms

• Abnormal eye movements due to extraocular muscle involvement
• Discharge from the eye (usually minimal)
• Feeling of pressure behind the eye
• Decreased color vision
• Halos around lights

Systemic Symptoms

When associated with autoimmune disease:

• Joint pain and swelling
• Skin rashes
• Fatigue
• Fever
• Weight loss
• Respiratory symptoms

Causes

Scleritis can result from various causes, with autoimmune diseases being the most common. Understanding the underlying cause is crucial for appropriate treatment.

Autoimmune Associations

Approximately 30-40% of scleritis cases are associated with systemic autoimmune conditions:

Rheumatologic Diseases

• Rheumatoid arthritis: Most common association (15-20% of cases)
• Granulomatosis with polyangiitis (Wegener's): Often presents with necrotizing scleritis
• Systemic lupus erythematosus: Can cause various ocular manifestations
• Relapsing polychondritis: Affects cartilage and may involve sclera
• Ankylosing spondylitis: Associated with anterior uveitis and scleritis
• Psoriatic arthritis: Less common but possible association

Vasculitic Disorders

• Polyarteritis nodosa
• Giant cell arteritis
• Behçet's disease
• Cogan's syndrome

Infectious Causes

• Bacterial: Tuberculosis, syphilis, Lyme disease
• Viral: Herpes zoster, herpes simplex
• Fungal: Aspergillosis (rare)
• Parasitic: Toxoplasmosis, acanthamoeba

Post-Surgical Causes

• Post-cataract surgery (surgically induced necrotizing scleritis)
• Post-pterygium excision
• Post-retinal detachment surgery
• Following scleral buckle procedures

Other Causes

• Metabolic: Gout (rare)
• Medications: Bisphosphonates (rare)
• Trauma: Penetrating or blunt trauma
• Chemical injury: Alkali burns
• Idiopathic: No identifiable cause (50% of cases)

Pathophysiology

The inflammatory process in scleritis involves:

• T-cell mediated immune response
• Immune complex deposition
• Vasculitis of episcleral and scleral vessels
• Release of inflammatory mediators
• Matrix metalloproteinase activation leading to scleral degradation

Risk Factors

Several factors increase the likelihood of developing scleritis:

Demographic Factors

• Age: Peak incidence between 40-60 years
• Gender: Women affected more than men (2:1 ratio)
• Race: No specific racial predilection
• Geographic location: Higher in areas with endemic infections

Medical History

• Previous episodes of scleritis or episcleritis
• History of autoimmune disease
• Family history of autoimmune conditions
• Previous eye surgery
• History of eye trauma
• Recurrent eye infections

Systemic Conditions

• Active rheumatoid arthritis
• Uncontrolled systemic vasculitis
• Inflammatory bowel disease
• Connective tissue disorders
• Immunosuppression

Environmental Factors

• Occupational exposure to chemicals
• Contact with infectious agents
• Living in endemic areas for certain infections
• Poor access to healthcare

Medication-Related Risks

• Long-term bisphosphonate use
• Certain chemotherapy agents
• Some antibiotics (rare)

Diagnosis

Diagnosing scleritis requires a comprehensive ophthalmologic examination and often systemic evaluation to identify underlying causes.

Clinical Examination

Ophthalmologic Assessment

• Visual acuity testing: May be reduced in severe cases
• Slit lamp examination: Detailed view of scleral inflammation
• Dilated fundus examination: Check for posterior involvement
• Intraocular pressure measurement: May be elevated
• Phenylephrine test: Helps distinguish from episcleritis

Characteristic Findings

• Deep scleral vessel engorgement
• Violaceous hue to the sclera
• Scleral edema and thickening
• Nodules or areas of necrosis
• Avascular areas (in necrotizing scleritis)

Imaging Studies

• B-scan ultrasonography: Shows scleral thickening, fluid in Tenon's space
• Anterior segment OCT: Detailed scleral structure
• CT/MRI orbits: For posterior scleritis evaluation
• Ultrasound biomicroscopy: High-resolution imaging

Laboratory Tests

Routine Tests

• Complete blood count with differential
• Erythrocyte sedimentation rate (ESR)
• C-reactive protein (CRP)
• Comprehensive metabolic panel
• Urinalysis

Autoimmune Workup

• Rheumatoid factor (RF)
• Anti-cyclic citrullinated peptide (anti-CCP)
• Antinuclear antibody (ANA)
• Anti-neutrophil cytoplasmic antibodies (ANCA)
• Anti-double-stranded DNA
• Complement levels (C3, C4)

Infectious Workup

• Syphilis serology (RPR/VDRL, FTA-ABS)
• Tuberculosis testing (TB skin test or QuantiFERON)
• Lyme titers if endemic area
• Herpes simplex/zoster antibodies if suspected

Differential Diagnosis

• Episcleritis: Milder, superficial inflammation
• Conjunctivitis: More discharge, less pain
• Anterior uveitis: Photophobia, cells in anterior chamber
• Acute angle-closure glaucoma: Elevated pressure, corneal edema
• Orbital cellulitis: Lid swelling, proptosis
• Pinguecula/pterygium: Visible growth on conjunctiva

Treatment Options

Treatment of scleritis requires aggressive anti-inflammatory therapy and management of any underlying systemic disease. The approach depends on the type and severity of scleritis.

First-Line Treatment

Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)

• Oral NSAIDs: Indomethacin 25-50mg TID, Naproxen 500mg BID
• Effective for mild to moderate non-necrotizing anterior scleritis
• Requires 2-3 weeks for full effect
• Monitor for GI side effects
• Consider gastroprotection

Corticosteroids

• Topical: Limited efficacy, adjunct therapy only
• Periocular injections: For localized disease
• Oral prednisone: 1mg/kg/day for severe cases
• Gradual taper over weeks to months
• Monitor for systemic side effects

Second-Line Treatment

Immunosuppressive Agents

• Methotrexate: 7.5-25mg weekly, steroid-sparing agent
• Azathioprine: 1-2.5mg/kg/day
• Mycophenolate mofetil: 1-3g/day
• Cyclosporine: 2.5-5mg/kg/day
• Regular monitoring of blood counts and liver function

Biologic Agents

• Infliximab: For refractory cases
• Adalimumab: TNF-alpha inhibitor
• Rituximab: For severe, sight-threatening disease
• Particularly useful in vasculitis-associated scleritis

Treatment by Type

Diffuse Anterior Scleritis

• Start with oral NSAIDs
• Add corticosteroids if no response in 2-3 weeks
• Consider immunosuppression for recurrent cases

Nodular Anterior Scleritis

• Similar to diffuse, may require longer treatment
• Periocular steroids can be helpful
• Close monitoring for progression

Necrotizing Scleritis

• Requires immediate aggressive treatment
• High-dose systemic corticosteroids
• Early immunosuppression
• May need IV pulse steroids initially
• Consider biologics for severe cases

Posterior Scleritis

• Systemic corticosteroids first-line
• Often requires immunosuppression
• Monitor for retinal complications

Adjunctive Therapy

• Cycloplegic drops: For associated uveitis
• Artificial tears: For comfort
• Sunglasses: For photophobia
• Pain management: Acetaminophen, avoid additional NSAIDs

Surgical Management

Reserved for complications:

• Scleral patch grafting for perforation
• Corneal transplant for corneal involvement
• Glaucoma surgery if needed
• Repair of scleral defects

Prevention

While scleritis cannot always be prevented, certain measures can reduce the risk of occurrence or recurrence.

Primary Prevention

• Early treatment of autoimmune diseases
• Regular monitoring if at high risk
• Prompt treatment of eye infections
• Protection from eye trauma
• Avoid known triggers

Management of Underlying Conditions

• Optimal control of rheumatoid arthritis
• Regular rheumatology follow-up
• Compliance with systemic medications
• Monitor disease activity markers
• Address flares promptly

Lifestyle Modifications

• Stress management techniques
• Adequate sleep and rest
• Balanced nutrition
• Smoking cessation
• UV protection for eyes

Post-Surgical Precautions

• Careful surgical technique
• Appropriate post-operative care
• Early recognition of inflammation
• Prophylactic anti-inflammatory treatment if high risk

Monitoring and Follow-up

• Regular ophthalmology visits
• Self-monitoring for symptoms
• Maintain treatment compliance
• Report new symptoms promptly
• Keep emergency contact information

When to See a Doctor

Scleritis is a serious condition requiring prompt medical attention. Early treatment can prevent vision-threatening complications.

Seek Immediate Emergency Care

• Severe eye pain not relieved by over-the-counter pain medication
• Sudden vision loss or significant vision changes
• Eye pain with nausea and vomiting
• Signs of perforation (sudden pain relief, vision loss)
• Severe headache with eye symptoms
• Eye trauma followed by pain and redness

See an Ophthalmologist Urgently

• Deep eye redness that doesn't improve
• Eye pain that worsens at night
• Eye pain with movement
• Light sensitivity with eye pain
• Recurrent episodes of eye inflammation
• Known autoimmune disease with new eye symptoms

Schedule an Appointment For

• Mild eye discomfort persisting over days
• History of scleritis with new symptoms
• Need for medication refills or monitoring
• Side effects from treatment
• Questions about prevention strategies

Warning Signs of Complications

• Progressive vision deterioration
• Appearance of dark spots on sclera
• Bulging of the eye
• Double vision
• Persistent high eye pressure

Related Conditions

Frequently Asked Questions