Necrotizing Scleritis

Definition & Causes - Scleral Siege

• Definition: Severe, destructive scleral inflammation with scleral thinning, necrosis; risk of perforation. Intense, boring pain is hallmark.
• Types:
  • Necrotizing with inflammation: Acutely painful.
  • Necrotizing without inflammation (Scleromalacia Perforans): Often painless; typically in longstanding Rheumatoid Arthritis.
• Primary Associations:
  • Systemic Autoimmune (most common, ≈50-60%):
    • Rheumatoid Arthritis (RA)
    • Granulomatosis with Polyangiitis (GPA)
    • Systemic Lupus Erythematosus (SLE)
    • Relapsing Polychondritis
  • Infectious (rare): Herpes Zoster, TB, Syphilis.
  • Surgically-induced: Post-operative.

⭐ Most common association of necrotizing scleritis is with systemic autoimmune diseases, particularly Rheumatoid Arthritis.

Clinical Picture - Eye on Fire

• Pain: Severe, boring, deep ocular pain.
  • Radiates: Temple, jaw, sinuses.
  • Nocturnal: Characteristically awakens patient at night.
• Redness: Intense, violaceous, "beefy-red" diffuse or nodular congestion; non-blanching with topical phenylephrine.
• Photophobia, lacrimation.
• ↓ Vision: Often progressive, can be severe.
• Scleral Appearance:
  • Thinning: Sclera may appear translucent, revealing underlying bluish uvea.
  • Avascular patches: Indicative of necrosis.
  • High risk of scleral melt and perforation.
• Commonly associated with systemic autoimmune diseases (e.g., Rheumatoid Arthritis, GPA, SLE).

⭐ The hallmark symptom is severe, boring ocular pain that may radiate to the temple, jaw, or sinuses, and characteristically awakens the patient at night.

Diagnosis & Workup - Unmasking the Culprit

• Slit-lamp Exam: Confirms scleral thinning, edema, avascular patches, and inflammation. Note extreme pain.
• Imaging:
  • B-scan Ultrasonography: Assesses posterior involvement, scleral thickness.
  • Ultrasound Biomicroscopy (UBM): Details anterior scleral changes.
• Systemic Evaluation (Crucial):
  • Inflammatory markers: ESR, CRP.
  • Autoantibodies: RF, anti-CCP, ANCA, ANA.
  • Chest X-ray; consider infectious screen (e.g., syphilis, TB).

⭐ B-scan ultrasonography is invaluable for assessing posterior scleritis, scleral thickness, and associated fluid or choroidal detachment.

Complications & Outlook - Danger Zone

• Scleral thinning → melt → perforation (esp. scleromalacia perforans)
• Uveitis (anterior/posterior), PUK, glaucoma, cataract
• Retinal detachment, choroidal effusion, optic neuropathy
• Severe, irreversible vision loss; globe deformity, phthisis bulbi
• Outlook: Guarded. Requires prompt, aggressive immunosuppression.
• High morbidity; mortality risk if systemic vasculitis untreated.

⭐ Scleral perforation is a dreaded complication, especially in the 'scleromalacia perforans' variant, leading to potential globe rupture and severe vision loss. A

Treatment Strategy - Quelling the Flames

• Primary Goal: Arrest inflammation, alleviate pain, prevent scleral melt & vision loss.
• Cornerstone: Prompt, aggressive systemic immunosuppression.

  ⭐ Aggressive systemic immunosuppression (e.g., corticosteroids combined with cyclophosphamide or biologic agents) is the mainstay of treatment for necrotizing scleritis to prevent visual loss and systemic complications.

• Initial Regimen:
  • Systemic Corticosteroids: High-dose (e.g., IV Methylprednisolone pulse, then oral Prednisolone 1-1.5 mg/kg/day).
  • PLUS Immunosuppressive agent: Cyclophosphamide (IV or oral), Methotrexate, Azathioprine, Mycophenolate.
• Refractory/Severe Disease:
  • Biologic agents (e.g., Infliximab, Adalimumab, Rituximab).
• ⚠️ Avoid: Topical steroids alone (ineffective, risk masking perforation).
• Surgery: Reserved for complications (e.g., tectonic scleral patch graft for perforation).

High‑Yield Points - ⚡ Biggest Takeaways

• Most severe and destructive scleritis, often causing significant visual loss.
• Strong association with systemic autoimmune diseases (e.g., Rheumatoid Arthritis, ANCA-vasculitis).
• Intense, boring, constant pain, often worse at night and radiating.
• High risk of scleral thinning, staphyloma, and globe perforation.
• Requires prompt, aggressive systemic immunosuppression (corticosteroids, cytotoxic agents).
• Scleromalacia perforans: a specific painless necrotizing variant in long-standing Rheumatoid Arthritis.