Differential Diagnosis for a 2 Week Old Baby with Eye Crusting and Discharge

Single Most Likely Diagnosis

• Chemosis and blocked tear ducts: This condition is common in newborns due to the underdeveloped tear ducts, leading to accumulation of tears and subsequent crusting and discharge without significant scleral or conjunctival involvement.

Other Likely Diagnoses

• Neonatal conjunctivitis (chemical): Although the question specifies no scleral and conjunctival involvement, chemical conjunctivitis from prophylactic eye drops given at birth could still cause discharge and crusting.
• Allergic conjunctivitis: Though less common in newborns, exposure to allergens could potentially cause an allergic reaction leading to eye crusting and discharge.

Do Not Miss Diagnoses

• Gonococcal conjunctivitis: A serious and sight-threatening condition if not promptly treated. It can present with severe discharge and is a must to rule out, especially if there's a history of maternal gonorrhea.
• Chlamydial conjunctivitis: Another critical condition that requires early diagnosis and treatment to prevent long-term vision problems.
• Herpes simplex virus (HSV) conjunctivitis: Can lead to serious complications, including corneal ulcers and vision loss, making prompt diagnosis crucial.

Rare Diagnoses

• Dacryocystitis: Infection of the lacrimal sac, which could present with discharge and crusting, though it's less common in newborns without a history of trauma or specific predisposing factors.
• Congenital glaucoma: Though primarily associated with corneal edema, photophobia, and blepharospasm, it could potentially cause excessive tearing leading to crusting, but this would be accompanied by other significant signs.