Ophthalmologists Miss Claire Daniel and Miss Lucy Barker describe the management of this common condition
A 71-year-old woman presents with a one-day history of a rash on the right of her forehead and intermittent sharp pain extending to the scalp. Her right eye is slightly red but there is no ocular pain. She had chicken pox when aged 11 and thoracic shingles around 10 years ago – and has had malaise and fever for the past week. Best-corrected visual acuity is 6/6 in both eyes.
Examination reveals a papular-vesicular rash in the ophthalmic distribution of the trigeminal nerve, extending to the hairline and onto the upper lid, which is slightly swollen. The skin is hyperaesthetic. The right eye is slightly injected with a clear cornea and quiet anterior chamber. Intraocular pressure and fundal examination are normal. The patient is diagnosed with herpes zoster ophthalmicus and started on oral aciclovir 800mg, five times per day for one week.
Herpes zoster ophthalmicus is relatively common and is caused by reactivation of the varicella zoster virus, which initially presents as chicken pox. The trigger for reactivation is not understood, but is most common in the immunocompromised and elderly – and is particularly severe in patients with HIV.1 The incidence of shingles (both thoracic and ophthalmic) is three in 1,000 per year, rising to 10 in 1,000 per year by the age of 80, with up to 50% of those aged 90 or over having experienced it.2
• Viral symptoms preceding the rash.
• Neuralgia preceding the rash may persist for several months.
• Rapidly progressing rash, obeying the vertical midline. It may be discrete and scattered or confluent in severe cases.
• Rash on the tip of the nose indicates significant risk of ocular involvement.3
• Localised swelling – including the eyelids – which may cross over to the contralateral side, giving a false impression of bilateral disease.
• Conjunctivitis is common, as is focal inflammation of the episclera or, more rarely, the sclera.
• Keratitis with reduced corneal sensation occurs in up to 65% of patients. Acute epithelial keratitis with pseudodendrites is common and is characterised by non-ulcerating corneal lesions that stain poorly with fluorescein.
• Up to 40% of patients may develop anterior uveitis.
• Optic neuritis, cranial nerve palsies, retinal vasculitis, central retinal vein or arterial occlusion and thrombophlebitis are associated, but uncommon.
• Atopic dermatitis – less painful, itchy and unlikely to obey the midline.
• Herpes simplex blepharoconjunctivitis – similar vesicular lesions but focused more around the eye.
• Conjunctivitis – no associated rash and less painful.
• Keratitis – no associated rash or neuralgia.
• Impetigo – honey-coloured crust on bullous skin lesions. It can occur anywhere on the body and may spread, and is unlikely to obey the midline.
• Trigeminal neuralgia – no rash or ocular signs.
• Assess rash – does it obey the midline? Is it papular or vesicular?
• Check visual acuity.
• Check corneal sensation.
• Instil fluorescein to assess for corneal lesions.
• Assess ocular motility.
• Urgently refer any patient with reduced visual acuity or limited eye movement.
• Early referral is required for ocular discomfort or photophobia.
• All patients need examination to exclude ocular involvement.
• Advise patients to go to eye casualty if pain, redness, photophobia or loss of vision develops.
• Oral aciclovir 800mg five times per day for seven to 10 days, ideally starting within 72 hours of rash onset.
• Treat mild ocular discomfort with chloramphenicol ointment or lubricant drops.
• Anterior uveitis and keratitis will be treated with topical steroids after examination by an ophthalmologist.
• Treat post-herpetic neuralgia in primary care with capsaicin cream 0.025% or 0.075% qds – this takes two to three weeks to work.
• More severe neuralgia may need treatment with oral amitriptyline or referral to a pain clinic.
Miss Claire Daniel is a consultant ophthalmic surgeon and Miss Lucy Barker is a specialist registrar at Moorfields Eye Hospital, London
1 Gupta N, Sachdev R, Sinha R et al. Herpes zoster ophthalmicus: disease spectrum in young adults. Middle East Afr J Ophthalmol 2011;18:178-82
2 Jonhson RW and Whitton TL. Management of herpes zoster (shingles) and post-herpetic neuralgia. Expert Opin Pharmacother 2004;5:551-9