Differential Diagnosis for Unilateral Photophobia in a 20-year-old
Single Most Likely Diagnosis
- Migraine: This is often the most common cause of unilateral photophobia, especially in a young adult. Migraines can present with sensitivity to light, sound, and sometimes nausea and vomiting, and are frequently unilateral.
Other Likely Diagnoses
- Cluster Headache: These are severe, unilateral headaches that can be accompanied by photophobia and are more common in young adults.
- Optic Neuritis: Inflammation of the optic nerve can cause pain with eye movement and sensitivity to light, often presenting unilaterally.
- Sinusitis: Infection or inflammation of the sinuses, especially the frontal or ethmoid sinuses, can cause unilateral facial pain and photophobia.
- Dry Eye Syndrome: Although less common as a primary cause of unilateral photophobia, severe dry eye can lead to significant discomfort and light sensitivity.
Do Not Miss Diagnoses
- Acute Angle-Closure Glaucoma: A medical emergency that can cause severe, unilateral eye pain, redness, and photophobia. It requires immediate treatment to prevent vision loss.
- Meningitis: Inflammation of the protective membranes covering the brain and spinal cord, which can present with photophobia, fever, and stiff neck.
- Encephalitis: Inflammation of the brain tissue, which can cause photophobia along with fever, confusion, and sometimes seizures.
- Temporal Arteritis: Inflammation of the blood vessels in the head, which can cause unilateral headaches, jaw claudication, and visual disturbances, including photophobia.
Rare Diagnoses
- Trigeminal Neuralgia: A chronic pain condition that affects the trigeminal nerve, which can cause intense, shock-like or stabbing pain in parts of the face, potentially accompanied by photophobia.
- Idiopathic Intracranial Hypertension (IIH): Also known as pseudotumor cerebri, this condition involves high pressure within the skull without any obvious cause, leading to symptoms like headache, vision changes, and sometimes photophobia.
- Ocular Migraine: A condition that can cause temporary vision loss or blindness in one eye, accompanied by a headache and photophobia, though the visual symptoms typically resolve within an hour.