Pinguecula: This condition is characterized by the formation of thick, white, or yellowish patches on the sclera, often adjacent to the limbus. It is usually caused by chronic exposure to ultraviolet light, dust, and wind, making it a common finding in individuals who spend a lot of time outdoors.

Scleral Plaques: These are areas of thickened sclera that can appear as white lines or patches. They can be associated with various conditions, including rheumatoid arthritis and other autoimmune diseases.
Scleromalacia Perforans: A rare form of scleritis characterized by thinning of the sclera, which can sometimes appear as white lines due to the underlying inflammation and tissue damage.

Scleritis: Although scleritis typically presents with redness, pain, and tenderness of the eye, some forms (like posterior scleritis) might not have the classic signs of inflammation. Missing this diagnosis could lead to severe complications, including vision loss.
Systemic Lupus Erythematosus (SLE): SLE can cause a variety of eye symptoms, including scleritis and retinal vasculitis. It's crucial to consider SLE in the differential diagnosis due to its potential for severe systemic and ocular complications.

Sarcoidosis: This systemic disease can affect the eyes in various ways, including uveitis, retinal vasculitis, and occasionally, scleral involvement. While less common, sarcoidosis should be considered in patients with unexplained ocular findings and systemic symptoms.
Relapsing Polychondritis: A rare autoimmune disorder that can affect the cartilaginous structures of the body, including the eyes. It may cause scleritis, among other ocular manifestations, and is important to recognize due to its potential for severe systemic complications.