Differential Diagnosis for Scleritis and Episcleritis

When differentiating between scleritis and episcleritis, it's crucial to consider the clinical presentation, symptoms, and potential underlying causes. Here's a structured approach to the differential diagnosis:

• Single Most Likely Diagnosis

  • Scleritis: This is often considered the primary diagnosis when a patient presents with severe, deep eye pain, tenderness to the touch, and inflammation of the sclera. Scleritis can lead to more serious complications if not properly managed.
  • Episcleritis: This condition is more superficial, involving the episclera, a thin layer on top of the sclera. It presents with eye redness, mild pain, and sometimes a nodular appearance but is generally less severe than scleritis.

• Other Likely Diagnoses

  • Conjunctivitis: This condition, often referred to as "pink eye," can mimic the redness and irritation seen in episcleritis but typically involves the conjunctiva and may have a discharge.
  • Keratitis: Inflammation of the cornea, which can cause pain, redness, and vision changes, might be considered, especially if the cornea is involved.
  • Uveitis: Inflammation of the uvea, which includes the iris, ciliary body, and choroid, can cause eye pain, redness, and sensitivity to light, and might be a differential in cases of posterior scleritis.

• Do Not Miss Diagnoses

  • Rheumatoid Arthritis: Scleritis can be associated with systemic autoimmune diseases like rheumatoid arthritis. Missing this connection could lead to inadequate management of the underlying condition.
  • Infectious Scleritis: Caused by bacteria, fungi, or viruses, this condition requires prompt identification and treatment to prevent serious complications, including vision loss.
  • Granulomatosis with Polyangiitis (GPA): Formerly known as Wegener's granulomatosis, GPA is a vasculitis that can cause scleritis among other systemic symptoms. It's crucial to diagnose and treat GPA to prevent organ damage.

• Rare Diagnoses

  • Relapsing Polychondritis: A rare autoimmune disorder that can cause inflammation in various cartilaginous structures, including the ears, nose, and eyes, potentially leading to scleritis.
  • Sarcoidosis: While more commonly associated with uveitis, sarcoidosis can rarely cause scleritis. It's a systemic disease that requires comprehensive management.
  • Polyarteritis Nodosa (PAN): A systemic vasculitis that can affect various parts of the body, including the eyes, leading to scleritis in rare cases.

Each of these conditions has distinct features and implications for patient management. A thorough clinical evaluation, including history, physical examination, and sometimes diagnostic tests, is essential for accurate diagnosis and appropriate treatment.