Scleritis | Geeky Medics

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Introduction

Scleritis is a painful, potentially sight-threatening inflammation of the sclera, the fibrous outer layer of the eye.¹ It can be associated with systemic autoimmune diseases and lead to severe ocular complications if not promptly treated.²

Scleritis accounts for approximately 6% of ocular inflammatory disease presentations and predominantly affects adults aged 30 – 60 years old.^{1, 3}

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Aetiology

Scleritis is often idiopathic.

Up to 50% of cases are associated with an underlying systemic autoimmune disease.¹ The most frequent cause is rheumatoid arthritis, followed by other connective tissue disorders, including systemic lupus erythematosus and granulomatosis with polyangiitis.

Infectious causes, while less common, are clinically important as they may require different management. These include herpes zoster, tuberculosis and syphilis, and should be considered particularly in immunocompromised patients. Scleritis can also occur following eye surgery or in patients with a history of ocular trauma.⁴

Pathophysiology

The sclera is a dense, collagen-rich connective tissue that forms the outer protective coat of the eye. Although relatively avascular, it is surrounded by the rich vascular episcleral and choroidal layers.

In scleritis, immune complex deposition and complement activation within the scleral vessels trigger a cascade of inflammation, leading to tissue oedema, cellular infiltration, and collagen degradation.¹

Types of scleritis

Scleritis can be classified based on anatomical location, into anterior and posterior forms:

• Anterior scleritis: the most common type of scleritis (90% of cases), typically with sectoral inflammation that involves the visible sclera
• Posterior scleritis: involves deeper, less accessible structures and may extend to the choroid, optic nerve, and retina, sometimes leading to complications (e.g. exudative retinal detachment or optic disc oedema)^{1, 5}

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Risk factors

Scleritis is frequently immune-mediated, and risk factors include:

• Rheumatoid arthritis: the most common systemic association (however, the most common ocular complication is dry eye syndrome)
• Other autoimmune diseases: including granulomatosis with polyangiitis, systemic lupus erythematosus and relapsing polychondritis
• Middle age (30-60 years): peak incidence in this age range
• Female sex
• Past ocular surgery or trauma: particularly relevant in infectious scleritis
• Immunosuppression: increasing susceptibility to opportunistic infections such as herpes zoster and tuberculosis.^{1, 3-4, 7}

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Clinical features

History

Patients with scleritis can present with unilateral or bilateral eye symptoms.

Typical symptoms of scleritis include:

• Severe ocular pain: often described as deep and aching, classically worse at night and with eye movement
• Red eye
• Photophobia: intolerance to sunlight or normal room lighting
• Blurred vision
• Tearing or epiphora: excessive watering of the eye due to irritation or inflammation

Other important areas to cover in the history include:

• Systemic autoimmune symptoms: joint pain, skin rashes, nasal/oral ulcers, or respiratory symptoms
• History of recent trauma or ocular surgery
• Immunosuppression: raises suspicion for opportunistic infectious causes

For more information, see the Geeky Medics guide to ophthalmic history taking.

Clinical examination

Patients with suspected scleritis should undergo a thorough examination, including visual acuity testing, anterior segment examination (ideally with a slit lamp), fundoscopy, and assessment of extraocular movements.

Typical clinical findings of scleritis include:

• Scleral injection: deep, violaceous (bluish-red) congestion of the scleral vessels leading to red eye
• Tenderness: marked pain on palpation of the globe
• Reduced visual acuity: particularly in posterior or necrotising forms
• Scleral thinning and blue discolouration: in necrotising scleritis
• Relative afferent pupillary defect (RAPD): if the optic nerve is involved, particularly in posterior scleritis
• Keratitis: with corneal infiltrates or thinning in anterior scleritis²

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Differential diagnoses

Differential diagnoses to consider in suspected scleritis include:

• Episcleritis: inflammation confined to the superficial episcleral tissue
• Conjunctivitis: can be caused by bacterial, viral infections, allergies, as well as prolonged contact lens use. Typically presents with diffuse redness, discharge and irritation but minimal pain.
• Blepharitis: inflammation of the eyelid margins associated with crusting and meibomian gland dysfunction. Symptoms are localised to the eyelid rather than the globe, with no significant ocular pain or scleral tenderness.
• Anterior uveitis: inflammation of the iris and ciliary body, presenting with photophobia, aching eye pain and ciliary injection. The pain is typically less severe and lacks the marked scleral tenderness characteristic of scleritis. 

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Investigations

Scleritis is a clinical diagnosis, but investigations can help identify underlying causes and potential complications.

Bedside investigations

Relevant bedside investigations include:

• Urinalysis: for haematuria/proteinuria in renal vasculitis
• Scleral biopsy with smears or cultures: in infectious scleritis

Laboratory investigations

Relevant laboratory investigations for suspected autoimmune or connective tissue disease include:

• Erythrocyte sedimentation rate (ESR)/C-reactive protein (CRP): for active disease
• Serum autoantibody screen (e.g. ANA, anti-DNA antibodies, rheumatoid factor, ANCA, anti-CCP antibodies)
• HLA-B27

Imaging

Relevant imaging includes:

• Orbital ultrasound: in posterior scleritis, which can show scleral thickening or a ‘T sign’ where fluid accumulates at the back of the eye
• CT/MRI: if orbital ultrasound is inconclusive, or when further evaluation is required to assess posterior scleritis, orbital involvement or associated complications in greater detail. Findings may include scleral enhancement, scleral thickening, and focal periscleral cellulitis.
• Chest X-ray/CT thorax: if granulomatosis with polyangiitis (GPA) or TB is suspected⁸

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Management

Medical management

If scleritis is suspected, an urgent, same-day ophthalmology referral is required.

In non-necrotising scleritis, topical corticosteroid and oral nonsteroidal anti-inflammatory drugs (NSAIDs) are considered the first-line therapy.

Oral corticosteroids can be used in cases that do not respond to topical corticosteroids and in cases of posterior scleritis and necrotising scleritis.

Immunosuppressants and biologics are also recognised in treating necrotising and posterior scleritis.⁹

Surgical management

In cases where scleritis has led to scleral perforation or excessive scleral thinning, surgery may be indicated, including scleral grafts or tectonic support.¹⁰

Follow-up for scleritis depends on the patient’s clinical response, where medication modifications or dose adjustments may be required.

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Complications

Complications of scleritis include:

• Scleral and corneal thinning
• Globe perforation
• Uveitis
• Cataracts
• Glaucoma
• Optic disc oedema
• Exudative retinal detachment

These complications can lead to long-term eye pain and/or vision loss.

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Reviewer

Dr Suzannah Bell

Ophthalmology Registrar

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Editor

Dr Jamie Scriven

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References

1. Okhravi N, Odufuwa B, McCluskey P, et al. Scleritis. Survey of Ophthalmology. 2005. Available from: [LINK].
2. Syed ZA. Scleritis. MSD Manual, Professional Version. 2025. Available from: [LINK].
3. Sainz de la Maza M, Foster CS, Jabbur NS. Scleritis associated with systemic vasculitic diseases. Ophthalmology. 1995. Available from: [LINK].
4. Sharma S, Sheth JU, Murthy SI. Infectious scleritis: a review of etiologies, clinical features, and management strategies. Frontiers. 2025. Available from: [LINK].
5. Lavric A, Gonzalez-Lopez JJ, Majumder PD, et al. Posterior Scleritis: Analysis of Epidemiology, Clinical Factors, and Risk of Recurrence in a Cohort of 114 Patients. Ocular Immunology and Inflammation. 2015. Available from: [LINK].
6. Lagina A and Ramphul K. Scleritis. StatPearls. 2023. Available at: [LINK].
7. Akpek EK, Thorne JE, Qazi FA, et al. Evaluation of patients with scleritis for systemic disease. Ophthalmology. 2004. Available from: [LINK].
8. Diogo MC, Jager MJ, Ferreira TA. CT and MR Imaging in the Diagnosis of Scleritis. American Journal of Neuroradiology. 2016. Available from: [LINK].
9. Dutta Majumder P, Agrawal R, McCluskey P, et al. Current Approach for the Diagnosis and Management of Noninfective Scleritis. Asia-Pacific Journal of Ophthalmology. 2020. Available from: [LINK].
10. Nguyen QD and Foster CS. Scleral Patch Graft in the Management of Necrotizing Scleritis. International Ophthalmology Clinics. 1999. Available from: [LINK].

Image references

• Figure 1. Promelle V, Goeb V, Gueudry J. Figure 1 in Rheumatoid Arthritis Associated Episcleritis and Scleritis: An Update on Treatment Perspectives. Journal of Clinical Medicine. 2021. Licence: [CC BY 4.0].
• Figure 2. Butler L, Tomkins-Netzer O, Reiser O, et al. Anterior non-necrotizing diffuse scleritis. In: Management of Scleritis in Older Adults. Drugs and Aging. 2024. Licence: [CC BY-NC 4.0].
• Figure 3. Ophthalmic Atlas Images by EyeRounds. Scleritis. Figure 1. Licence: [CC BY-NC-ND 3.0].
• Figure 4. Ophthalmic Atlas Images by EyeRounds. Scleritis. Figure 2. Licence: [CC BY-NC-ND 3.0].

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