(BMJ)—A man in his 60s presented with a 3-day hx of painful red lesions on his nose and palate. He had a stinging/itchy sensation on the external aspect of his nose for 2 days before the rash appeared. Exam: multiple plaques with crusted blisters on R side of nose, midface, upper eyelid, and forehead; oral ulcerations. Slit-lamp: (+) cells in anterior chamber. What’s the dx?
Mucous membrane pemphigoid
Pemphigus vulgaris
Herpes zoster
Behcet disease
Erythema multiforme major
You are correct. A Tzanck test of the lesions and cx of vesicles confirmed herpes zoster infection.

This patient had involvement of the maxillary (midface and hard palate) and ophthalmic branches of the trigeminal nerve. In herpes zoster ophthalmicus, lesions of the scalp, forehead, and upper eyelid are caused by involvement of the frontal nerve branch of the ophthalmic nerve. Hutchinson sign—lesions in the area of the nasociliary dermatome (inner corner of eye, tip of nose, root or side of nose)—occurs in >50% of patients with herpes zoster ophthalmicus and is a strong predictor of ocular inflammation and corneal denervation (86% and 51%, respectively). Acute uveitis, the second-most-common ophthalmic complication of herpes zoster ophthalmicus, after conjunctivitis, can lead to acute retinal necrosis.

In this patient, the skin lesions subsided with IV acyclovir tx. The anterior uveitis resolved without sequelae after 1 month of topical chloramphenicol and prednisolone acetate eye drops.

BMJ 2020;371:m3778