Herpes zoster ophthalmicus
Herpes zoster ophthalmicus (HZO), also known as ophthalmic zoster, is shingles involving the eye. Symptoms generally include a rash of the forehead with swelling of the eyelid. There may also be eye pain, eye redness, and light sensitivity. Before the rash appears tingling may occur in the forehead along with a fever. Complications may include vision loss, increased pressure within the eye, and chronic pain.
The underlying mechanism involves a reactivation of the varicella zoster virus within the ophthalmic nerve (the first division of the trigeminal nerve). Risk factors include poor immune function, psychological stress, and older age. Diagnosis is generally based on symptoms.
Some people have a greater risk of getting shingles. This includes people who have medical conditions that keep their immune systems from working properly, such as certain cancers like leukemia and lymphoma, and human immunodeficiency virus (HIV) receive drugs that keep their immune systems from working properly, such as steroids and drugs that are given after organ transplantation
Treatment is generally with antiviral pills such as acyclovir. Steroid eye-drops and drops to dilate the pupil may also be used. The herpes zoster vaccine is recommended for prevention in those over the age of 50. Shingles affects up to half a million people in the United States a year of which 10% to 25% involve the eye.
Signs and symptoms
- Viral prodrome
- Preherpetic neuralgia
- Rash, transitioning from papules to vesicles to pustules to scabs. The frontal nerve is more commonly affected than the nasociliary nerve or lacrimal nerve.
- Hutchinson's sign: cutaneous involvement of the tip of the nose, indicating nasociliary nerve involvement. A positive Hutchinson's sign increases the likelihood of ocular complications associated with HZO.
- Disseminated distribution in individuals with immunodeficiency.
- Epithelial: punctate epithelial erosions and pseudodendrites: often have anterior stromal infiltrates. Onset 2 to 3 days after the onset of the rash, resolving within 2–3 weeks. Common.
- Nummular keratitis: have anterior stromal granular deposits. Occurs within 10 days of onset of rash. Uncommon
- Necrotising interstitial keratitis: Characterised by stromal infiltrates, corneal thinning and possibly perforation. Occurs between 3 months and several years after onset of rash. Rare.
- Disciform Keratitis (Disciform Endotheliitis): a disc of corneal oedema, folds in Descemet's membrane, mild inflammation evident within the anterior chamber and fine keratic precipitates. Chronic. Occurs between 3 months and several years after the onset of the rash. Uncommon.
- Neurotrophic: corneal nerve damage causes persistent epithelial defect, thinning and even perforation. Cornea becomes susceptible to bacterial and fungal keratitis. Chronic. Late onset. Uncommon.
- Mucous plaques: linear grey elevations loosely adherent to the underlying diseased epithelium/stroma. Chronic. Onset between 3 months and several years after the onset of the rash.
Anterior uveitis develops in 40–50% of cases with HZO within 2 weeks of onset of the skin rashes. Typical HZO keratitis at least mild iritis, especially if Hutchinson's sign is positive for the presence of vesicles upon the tip of the nose.
Treatment is usually with antivirals such as acyclovir or valacyclovir by mouth. There is uncertainty as to the difference in effect between these two antivirals. Antiviral eye drops have not been found to be useful. These medications work best if started within 3 days of the start of the rash.
To prevent spreading VZV to others:
- Cover the rash.
- Avoid touching or scratching the rash.
- Wash your hands often.
- Avoid contact with the following people until your rash crusts:
- pregnant women who have never had chickenpox or the chickenpox vaccine;
- premature or low birth weight infants; and
- people with weakened immune systems, such as people receiving immunosuppressive medications or undergoing chemotherapy, organ transplant recipients, and people with human immunodeficiency virus (HIV) infection.
|Wikimedia Commons has media related to Herpes zoster ophthalmicus.|