Differential Diagnosis for Swollen Eyes after Scratching

• Single most likely diagnosis
  • Allergic conjunctivitis: This is the most likely diagnosis given the symptoms of swollen eyes after scratching, which could be an allergic reaction to something that came into contact with the eyes.
• Other Likely diagnoses
  • Dry eye syndrome: Scratching the eyes can further irritate them if they are already dry, leading to swelling.
  • Blepharitis: Inflammation of the eyelids can cause swelling and itching, leading to scratching.
  • Conjunctivitis (viral or bacterial): An infection could cause the eyes to become swollen and itchy.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Orbital cellulitis: A serious infection that can cause the tissues around the eye to become inflamed, which requires prompt medical attention.
  • Angioedema: A severe allergic reaction that can cause rapid swelling of the eyes and face, potentially leading to airway obstruction.
  • Herpes simplex keratitis: A viral infection that can cause inflammation of the cornea, leading to vision loss if not treated promptly.
• Rare diagnoses
  • Ocular rosacea: A condition that causes inflammation of the eyes and eyelids, which can lead to swelling and itching.
  • Atopic keratoconjunctivitis: A rare condition that causes inflammation of the eyes due to an allergic reaction, leading to swelling and itching.
  • Phlyctenular keratoconjunctivitis: A rare condition that causes inflammation of the eyes due to an allergic or immune reaction, leading to swelling and itching.