If there is a question of diagnosis, do a
Tzanck smear (see technique below). While oral or genital HSV is
usually painful, this is not always the case. Be suspicious,
especially with penile erosions and ulcers.
Treatment should be individualized.
Topical acyclovir ointment is useless. Tea bag soaks are quite
helpful to dry out the blisters. Have the patient make a cup of tea,
squeeze out the teabag, and then apply the bag to the lesions after it
has cooled. The residual tannic acid in a tea bag is a surprisingly
effective drying agent.
(a) Acyclovir
Oral acyclovir is effective only if
given EARLY in the herpetic episode. In addition, it is not useful
for the patient who gets only the occasional mild episode. Acyclovir
is helpful for patients with an initial outbreak. They are frequently
systemically ill and in pain.
For patients with recurrent disease,
acyclovir should be reserved for those patients whose outbreaks are
frequent, very painful, or have associated systemic findings (fever,
painful adenopathy, malaise, etc.) The dose for treatment of an acute
episode is 200 mg five times a day for 5 days. The use of 200 mg TID
to 400 mg BID is useful for suppression in patients with frequent
recurrences.
(b) Valacyclovir
This drug is a pro-drug of
acyclovir. Its mechanism of action is identical to acyclovir. The
advantage is that the medication needs to only be used twice a day
instead of five. The dose for recurrent HSV is 500 mg BID for 5
days. The use of 500 mg QD is useful for suppression.
(c)
Famcyclovir
The dose is 125 mg BID for 5 days.
(d)
Other Considerations
In
the case of genital HSV, evaluation for concomitant STD should be strongly
considered on an initial visit. STDs are a chummy group and are frequently
transmitted in twos or threes. Look for them!
Although patients are most infectious when they have active lesions, they may
continue to shed virus (albeit at a smaller rate) between outbreaks. As such,
barrier contraception (e.g. condoms) is recommended at all times unless a
couple is trying to conceive.
A couple trying to determine "who gave what to
whom and when" is engaged in a hopeless and psychologically destructive task.
Either partner may have had a dormant infection for weeks, months or even
years. While serologic testing for antibodies to HSV I and II is available, a
positive result is of little clinical utility because over 90 percent of
adults will test positive due to previous exposure to oral or genital HSV.
Instructions for performing a Tzank Smear
-
Open an intact vesicle at the edge
using a surgical blade. If no intact vesicles, gently soak off the crust.
-
Scrape the base of the vesicle (or
the advancing border from an erosion/ulcer after crust soaked off) and smear
on slide. Do not scrape to the point of bleeding, it makes the slide
difficult to interpret.
-
Tzank Smear |
Fix the slide using heat or 20
seconds in absolute alcohol.
-
Stain using Wright, Wright-Giemsa,
Pap, etc. stains following the lab's standard operating procedures manual.
-
Dry the slide using gentle blotting
motions of a paper towel and air movement.
-
Place 2 small drops of immersion
oil on slide and then mount a cover slip.
-
Scan under 10-X for presence of
multinucleated giant cells.
Written and revised by CAPT Dennis
A. Vidmar, MC, USN, Department of Military and Emergency
Medicine, and Department of Dermatology, Uniformed Services University
of the Health Sciences, Bethesda, MD (1999).
Additional images provided by CAPT Vidmar in
June, 2000, subsequent to the initial publication of this manual.
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