treatment
plan
Managing
Herpes Zoster Ophthalmicus, Part 2
BY
WILLIAM TOWNSEND, OD
Part 1 of this column
(July 2006) described the case of a 37-year-old female who suffered from dermal
and ocular complications of herpes zoster. In this column I'll focus on additional
signs and symptoms as well as management strategies for this painful condition.
Nailing the Diagnosis
Herpes zoster ophthalmicus (HZO) typically begins with neuralgia
of the lids followed up to a week later by the onset of dermal lesions. Hutchinson
observed the association between HZV involvement of the nose and HZO, but ocular
involvement can occur independently of nasal signs; one-third of patients who have
HZO do not display Hutchinson's sign.
In contrast to herpes simplex, HZV involves subdermal tissue and
thus may lead to scarring resulting in entropion, ectropion or trichiasis. Conjunctival
hemorrhages and vesicles with follicular hypertrophy and localized adeno-pathy are
common features of HZO. Nodular episcleritis and scleritis may present concurrently
or months after the skin lesions have resolved.
Keratitis occurs in over half of all cases of HZO; hypoesthesia
is a common finding in these individuals. Corneal lesions may form a diffuse superficial
punctate keratitis or a dendritic pattern that you could mistake for herpes simplex
keratitis (Figure 1). HZO dendrites differ from HSK in lacking terminal bulbs, and
wiping the surface of HZO lesions yields intact epithelium, whereas wiping HSK lesions
leaves full thickness epithelial ulcers. Anterior stromal infiltrates occur in 40
percent of HZO cases.
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Figure 1.
Dendritic pattern of HZO corneal lesions.
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Management Strategies
Initiating systemic antiviral treatment within 72 hours after
the onset of the skin lesions significantly reduces the probability of post-herpetic
neuralgia (PHN).
Use of oral acyclovir prescribed at 800mg PO 5 times per day early
in the course of the disease often reduces pain, duration of skin lesions and complications
of episcleritis, scleritis and keratitis. Oral antivirals dramatically reduce the
need for adjunctive steroid therapy. Newer antiviral agents famciclovir and valacyclovir
exhibit better oral bioavailability and require less frequent administration, typically
t.i.d. Concurrent use of oral steroids with antivirals may reduce dependence on
pain medications and hasten healing of skin lesions.
Topical steroids are also useful in treating corneal, scleral
and uveitic manifestations of the disease. Cycloplegic agents help minimize the
discomfort and complications of corneal and uveal disease. Steroids do not exacerbate
HZO keratitis as they do in herpes simplex keratitis. Taper steroids gradually,
over a period of weeks or even months.
PHN is difficult to treat and typically has a clinical course
of months or years. Skin lesions respond to Burrow's solutions, calamine lotions
and creams. Topical capsaicin reduces pain once skin lesions have healed. Oral cimetidine
can reduce itching and pain. Anticonvulsants such as gabapentin and carbamazine
can effectively treat PHN. Tricyclic antidepressants and narcotic analgesics can
minimize pain and discomfort.
You may find it useful to work with primary care providers and
pain specialists in managing patients suffering from severe PHN.
Dr. Townsend is in private
practice in Canyon, Texas, and is a consultant at the Amarillo VA Medical Center.
E-mail him at drbill1@cox.net.
Contact Lens Spectrum, Issue: October 2006