Differential Diagnosis for Patient with Vitelliform Macular Dystrophy on Phenylephrine, Tropicamide Eye Drop

Single Most Likely Diagnosis

• Allergic Reaction to Eye Drops: The patient's complaint of a swollen left eye after using Phenylephrine and Tropicamide eye drops suggests an allergic reaction. These medications can cause allergic reactions, including eyelid swelling, which is a common side effect.

Other Likely Diagnoses

• Angle-Closure Glaucoma: Phenylephrine can cause pupillary dilation, which may precipitate angle-closure glaucoma in susceptible individuals, leading to eye pain, redness, and vision loss.
• Uveitis: The use of tropicamide can potentially lead to uveitis, especially if the patient has a pre-existing condition. Uveitis can cause eye pain, redness, and vision problems.
• Blepharitis or Conjunctivitis: These are common conditions that can cause eye swelling and discomfort, possibly exacerbated by the use of eye drops.

Do Not Miss Diagnoses

• Endophthalmitis: Although rare, endophthalmitis is a serious infection that can occur after the use of eye drops, especially if the drops are contaminated or if the patient has a compromised corneal surface. It requires immediate medical attention.
• Corneal Ulcer: A corneal ulcer can develop due to an infection or as a complication of the eye drops, leading to severe eye pain, redness, and vision loss.
• Orbital Cellulitis: This is an infection of the tissues surrounding the eye, which can cause swelling, pain, and vision problems. It is a medical emergency.

Rare Diagnoses

• Steven-Johnson Syndrome: A rare but serious disorder of the skin and mucous membranes, often caused by an allergic reaction to medications, including eye drops. It can lead to severe eye and skin symptoms.
• Toxic Epidermal Necrolysis: Another rare, life-threatening skin condition usually triggered by medications, which can affect the eyes and lead to severe complications.

Red Flag

The red flag in this scenario is the sudden onset of eye swelling and vision affectation after starting the eye drops, which could indicate a serious condition such as angle-closure glaucoma, endophthalmitis, or orbital cellulitis.

Best Management

1. Immediate Ophthalmological Evaluation: The patient should be seen by an ophthalmologist as soon as possible to determine the cause of the swelling and vision problems.
2. Discontinue Offending Agent: Stop the use of Phenylephrine and Tropicamide eye drops until the cause of the symptoms is determined.
3. Supportive Care: Depending on the diagnosis, supportive care may include anti-allergic medications, antibiotics, or other treatments to manage symptoms and prevent further complications.
4. Monitor for Serious Conditions: Close monitoring for signs of serious conditions such as angle-closure glaucoma, endophthalmitis, or orbital cellulitis, and immediate intervention if suspected.