Differential Diagnosis for a 71-year-old Female Patient with an Isolated Red Eye
Single Most Likely Diagnosis
- Dry Eye Syndrome: This condition is common in elderly patients and can cause sudden onset of a red eye due to decreased tear production or altered tear composition. The patient's age and the absence of other systemic symptoms make this a plausible diagnosis.
Other Likely Diagnoses
- Conjunctivitis: This could be either viral or bacterial, and is a common cause of a red eye. The acute onset and isolated nature of the symptom suggest an infectious cause.
- Blepharitis: Inflammation of the eyelids can cause redness, itching, and irritation of the eye. It's a common condition that can occur at any age and might be related to poor eyelid hygiene or underlying conditions like rosacea.
- Corneal Abrasion: A scratch on the cornea can cause sudden pain, redness, and sensitivity to light. This could be due to trauma, contact lens use, or other foreign body exposure.
Do Not Miss Diagnoses
- Acute Angle-Closure Glaucoma: Although less common, this is a medical emergency that requires immediate attention. Symptoms include severe eye pain, redness, blurred vision, and possibly nausea and vomiting. Missing this diagnosis could lead to permanent vision loss.
- Endophthalmitis: A severe infection within the eye that can occur post-surgically or following an eye injury. It presents with severe pain, redness, and decreased vision, and is a medical emergency.
- Temporal Arteritis (Giant Cell Arteritis): This condition can cause a red eye due to ischemia and is associated with headache, jaw claudication, and visual disturbances. It's a medical emergency due to the risk of permanent vision loss if not promptly treated.
Rare Diagnoses
- Scleritis: Inflammation of the sclera, which can cause severe eye pain, redness, and tenderness. It's less common and can be associated with systemic autoimmune diseases.
- Uveitis: Inflammation of the uvea, which can cause eye pain, redness, and sensitivity to light. It has various causes, including autoimmune diseases, infections, and trauma, and can lead to complications if not treated properly.
- Carotid Artery Dissection: Although extremely rare as a cause of an isolated red eye, it can lead to ocular ischemic syndrome, presenting with eye pain and vision loss. It's a vascular emergency that requires immediate medical attention.