What are the causes of recurrent scleritis?

Causes of Recurrent Scleritis

Recurrent scleritis is most commonly associated with underlying systemic autoimmune diseases, particularly rheumatoid arthritis, ANCA-associated vasculitis (especially granulomatosis with polyangiitis), and inflammatory bowel disease, though up to one-third of cases remain idiopathic. 1, 2

Primary Systemic Associations

Rheumatic and Autoimmune Diseases

• Rheumatoid arthritis remains the single most common systemic disease associated with recurrent scleritis, accounting for the majority of rheumatic disease-related cases 1, 2
• Granulomatosis with polyangiitis (formerly Wegener's granulomatosis) is the most common vasculitis causing scleritis and should be considered especially in necrotizing presentations 1
• ANCA-associated vasculitides collectively represent a critical diagnostic consideration, as scleritis may precede systemic vasculitis diagnosis and signal life-threatening disease 2
• Systemic lupus erythematosus can manifest with recurrent scleritis episodes 3
• Spondyloarthropathies, including ankylosing spondylitis and reactive arthritis, are associated with recurrent anterior scleritis 4
• Inflammatory bowel disease (both Crohn's disease and ulcerative colitis) can present with scleritis flares 3

Emerging Associations

• IgG4-related disease has recently been recognized as a systemic association with scleritis and should be considered in the differential diagnosis 2

Infectious Causes (Must Be Excluded)

• Herpetic infections are regularly underestimated as a cause of recurrent scleritis and must be systematically excluded before attributing disease to autoimmune etiology 4
• Other infectious etiologies including tuberculosis, syphilis, and Lyme disease can cause recurrent inflammation 5

Clinical Patterns Suggesting Specific Etiologies

Necrotizing Scleritis

• Necrotizing anterior scleritis with inflammation is strongly associated with underlying autoimmune disease, particularly systemic vasculitis 1, 4
• Necrotizing scleritis without inflammation (scleromalacia perforans) typically reflects advanced, long-standing rheumatoid arthritis 4
• This subtype carries the highest risk of vision-threatening complications and systemic disease 1

Posterior Scleritis

• Posterior scleritis is frequently missed or underdiagnosed due to subtle clinical signs and protean manifestations 1
• When recurrent, it warrants particularly aggressive systemic workup 1

Idiopathic Disease

• Approximately two-thirds of scleritis cases are idiopathic (not associated with identifiable systemic disease), though these patients still require surveillance for development of systemic conditions 2, 5
• Idiopathic cases may still recur and require immunosuppressive therapy 2

Key Diagnostic Pitfalls

• Scleritis can precede the diagnosis of systemic autoimmune disease by months to years, particularly in ANCA-associated vasculitis 2
• Recurrent episodes should prompt repeated systemic evaluation even if initial workup was negative 5
• Cases showing resistance to conventional anti-inflammatory therapy or aggressive behavior are more likely to have underlying systemic disease 5

Associated Complications Indicating Systemic Disease

• Concurrent anterior uveitis and peripheral ulcerative keratitis are more common with necrotizing scleritis and suggest systemic autoimmune disease 1
• Bilateral involvement or rapidly progressive disease increases likelihood of systemic association 5