Differential Diagnosis for an 80-year-old with Left Eye Pain and a Rash Resembling Shingles
- Single most likely diagnosis:
- Herpes Zoster Ophthalmicus (HZO) - This condition is characterized by a painful rash resembling shingles in the distribution of the ophthalmic branch of the trigeminal nerve, which can cause eye pain. The presence of a rash that looks like shingles strongly suggests this diagnosis, especially given the patient's age and the involvement of one eye.
- Other Likely diagnoses:
- Acute Angle-Closure Glaucoma - Although the patient reports no visual disturbances, this condition can sometimes present with eye pain and is a medical emergency. The absence of visual symptoms does not rule out this diagnosis.
- Dry Eye Syndrome - This condition can cause eye pain and is common in the elderly. However, it would not typically cause a rash.
- Conjunctivitis or Keratitis - Infections or inflammations of the conjunctiva or cornea can cause eye pain and could be considered, especially if there are other symptoms like redness or discharge.
- Do Not Miss diagnoses:
- Central Retinal Artery Occlusion - This is an emergency that can cause sudden, painless loss of vision, but it's less likely given the presence of pain and a rash. However, any sudden change in vision warrants immediate investigation.
- Endophthalmitis - A severe inflammation of the interior of the eye, usually caused by infection. It's a rare but serious condition that requires prompt treatment.
- Orbital Cellulitis - An infection of the tissues surrounding the eye, which can cause pain, redness, and swelling. It's a serious condition that needs immediate medical attention.
- Rare diagnoses:
- Scleritis - Inflammation of the sclera, which can cause severe eye pain and is sometimes associated with systemic diseases. It's less common but should be considered in the differential diagnosis of eye pain.
- Migraine or Cluster Headaches - These can cause eye pain but would not typically be associated with a rash resembling shingles.
- Trigeminal Neuralgia - A condition that causes sudden, severe, shock-like pain around the eyes, lips, or nose mainly because of abnormal blood vessels pressing on the trigeminal nerve in the head. It's less likely given the rash but could be a consideration for the eye pain aspect.