Differential Diagnosis for a Bump Protruding from the White of a Person's Eye

Single Most Likely Diagnosis

• Pinguecula: A pinguecula is a yellowish patch or bump on the white of the eye, typically adjacent to the cornea. It's often related to UV exposure and is very common, making it the most likely diagnosis for a bump on the white of the eye.

Other Likely Diagnoses

• Pterygium: Similar to a pinguecula but grows onto the cornea, often referred to as "surfer's eye." It's also related to UV exposure and can cause a noticeable bump.
• Conjunctival Papilloma: A benign growth on the conjunctiva, which can appear as a bump. These are relatively common and can be caused by various factors, including viral infections.
• Chalazion: Although typically appearing on the eyelid, a large chalazion can sometimes be mistaken for a bump on the white of the eye if it's located near the lid margin and is large enough.

Do Not Miss Diagnoses

• Basal Cell Carcinoma: A type of skin cancer that can appear on the eye, including the white part. Although less common, missing this diagnosis could have serious consequences, including significant morbidity and potential for metastasis if left untreated.
• Squamous Cell Carcinoma: Another form of skin cancer that can appear as a bump on the white of the eye. Early detection is crucial for effective treatment and to prevent spread.
• Kaposi's Sarcoma: In immunocompromised patients, Kaposi's sarcoma can manifest as lesions on the eye, including the conjunctiva. Given its association with HIV/AIDS and other immunosuppressed states, it's a critical diagnosis not to miss.

Rare Diagnoses

• Conjunctival Lymphoma: A rare malignancy of the conjunctiva that can present as a bump or mass. Given its rarity and potential for aggressive behavior, it's essential to consider in the differential diagnosis.
• Dermoid Cyst: A benign cyst that can appear on the eye, often present from birth. It's a rare cause of a bump on the white of the eye but should be considered, especially in younger patients.
• Conjunctival Amyloidosis: A condition where amyloid deposits accumulate in the conjunctiva, potentially forming bumps or masses. It's rare and might be associated with systemic amyloidosis, making it an important diagnosis to consider.