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MANAGEMENT
OF OPPORTUNISTIC INFECTIONS
IN
HIV-POSITIV PATIENTS
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FACT
SHEETS
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Varicella-zoster
virus (VZV) infection
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A viral infection
Causative organisms
Varicella-zoster virus (VZV). VZV causes 2 clinically
distinct diseases. Varicella (or chickenpox) is a common
and extremely contagious acute illness that occurs in
epidemics among school-aged children and is characterized
by a generalized vesicular rash. VZV establishes latency
following primary infection. Reactivation of latent VZV
results in herpes zoster (or shingles), a localized cutaneous
eruption that is most common among the elderly.
Complications of both varicella and herpes zoster are
more frequent in immunocompromised patients. The incidence
of herpes zoster is greater in HIV-infected patients than
that in the general population and can occur at any CD4+
count.
Symptoms of active infection
Varicella
In most HIV-seropositive children, varicella does not
appear to be unusually severe, although some authors have
reported a longer duration of new lesion formation and
higher median lesion counts. An inverse correlation between
CD4+ lymphocyte counts and complication rates, such as
hemorrhagic skin lesions or bacterial superinfections,
has been suggested.
When chickenpox does occur in HIV-infected adults, the
infection may produce significant morbidity.
Cutaneous zoster
Most common form. Typically seen as a painful, dermatomal
eruption of vesicles, most frequently involving the head,
chest or arms or sacral nerve root distribution. Zoster
can be multidermatomal or involve widespread cutaneous
dissemination, and the lesions may be atypical-appearing
papules. Persistence and recurrence are common in patients
with more advanced HIV disease. Also, persistent pain
(postherpetic neuralgia) may complicate episodes of zoster.
Ocular zoster
Zoster ophthalmicus (involving the ophthalmic branch V1
of the trigeminal nerve) has a propensity to result in
conjunctival, corneal, anterior chamber, or retinal disease
that can be sight-threatening. Zoster retinitis results
in retinal detachment in most cases, and blindness is
a common complication.
Zoster meningoencephalitis
Cases of viral meningitis, myelitis and encephalitis,
including cases with one or more of these manifestations
combined, have all been reported as caused by VZV in patients
with AIDS. As with retinitis, the prognosis is poor. |
Herpes zoster ophthalmicus Hemorrhagic vesicles
and erosions on a background of erythema and edema in
early stage HIV disease. Note extension to maxillary
branch |
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Diagnostic procedures
Varicella
Distinctive appearance - a clinical diagnosis is usually
accurate.
Cutaneous zoster
The characteristic vesicular rash usually makes it an
obvious clinical diagnosis. If the presentation is atypical,
the diagnosis can best be confirmed by testing a smear
of a swab of the base of a skin lesion for the presence
of VZV antigen by a direct fluorescent antibody (DFA)
method.
Ocular zoster
VZV retinitis is a clinical diagnosis made by the typical
clinical appearance of the retina and confirmed by a
history of concurrent or recent cutaneous zoster.
VZV neurologic disease
This usually requires viral culture or antigen testing
of cerebrospinal fluid to confirm the diagnosis.
Treatment
Varicella
For HIV-infected children or adults with chickenpox,
most clinicians prescribe oral acyclovir at a dose of
20 mg/kg (up to 800 mg) four times daily for 5 days.
Cutaneous zoster
Data confirm the efficacy and safety of oral acyclovir
800 mg 5 times daily for herpes zoster in patients with
HIV infection. Times to cessation of new vesicle formation,
total crusting, and resolution of zoster-associated
pain were 3-4 days, 7-8 days and about 60 days respectively
(Antimicrob Agents Chemother 1998; 42: 1139).
The value of anti-VZV therapy in patients presenting
with herpes zoster of greater than 72 hours' duration
has not been determined. Patients who have signs of
ongoing VZV replication (as evidenced by new vesicle
formation) are likely to benefit.
Ocular zoster
These patients should be treated even if they present
beyond 72 hours, to reduce the risk of serious ocular
complications. Antiviral therapy is unlikely to be useful
for patients whose lesions are crusted or scabbed.
Zoster meningoencephalitis
Successful therapy of neurologic complications, including
myelitis, with intravenous acyclovir, has been reported.
Prophylaxis
Long-term administration of anti-herpesvirus drugs to
prevent recurrences of herpes zoster is not routinely
recommended in AIDS patients. Relapses should be treated
adequately.
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