Genital herpes
Definition
Infection of the genital skin or mucosa
with herpes simplex virus is called genital herpes. It is the most common cause
of ulcerative genital disease, and it is an important risk factor for
acquisition and transmission of human immunodeficiency virus. Genital herpes (GH)
is a chronic sexually transmitted viral disease, characterized by symptomatic and
asymptomatic viral shedding.
Etiology
Genital herpes simplex virus (HSV) infection
is primarily a disease of young adults transmitted by sexual contact. It is a recurrent, lifelong
infection. Seventy percent of transmission occurs during times of asymptomatic
HSV shedding. There are two serotypes: HSV-1 and HSV-2. Most genital cases are
caused by HSV-2, but the prevalence of genital herpes caused by HSV-1 began to
increase because of changes in sexual habits (following oral–genital contact).
Clinical Manifestation primary
genital herpes
Most individuals with primary infection are asymptomatic;
if symptomatic widespread areas are involved and can present as excruciatingly
painful, erosive balanitis, vulvitis, or vaginitis.
Vesicles appear approximately 6 days after
sexual contact. Vesicles become depressed in the center (umbilicated) and then
erode. Crusts form and the lesion heal in the next 1- 2 weeks. New vesicles
continuously develop over 7–14 days and the whole illness may last 3 weeks or
more. Vesicles are discrete. Scars form if
the inflammation has been intense. Discharge, dysuria, and inguinal
Inguinal/femoral lymph nodes may be enlarged and tender. Systemic complaints,
including fever, headache, malaise, and myalgias, are present in approximately
70% of patients.
Genital lesions in men typically occur on the
glans, prepuce or shaft of the penis, and
the buttocks are occasionally affected. Patients present with painful penile erosion
with edema and possible urinary retention, especially if uncircumcised. Crusts
do not form under the foreskin.
In male
homosexuals, herpes simplex infection occurs following anal
intercourse, characterized
by tenesmus, anal pain, discharge, and ulcerations in the perianal area and may extend into
anal canal and on the rectal mucosa.
In the female, painful
erosions
appear occur on the vulva and vagina. Lesions
are bilaterally symmetrical and often extensive. Lesions often also involve the
cervix, buttocks, and perineum. HSV cervicitis occurs in more than 80% of women
with primary infection. It can present as purulent or bloody vaginal discharge,
and examination reveals areas of diffuse or focal friability and redness,
extensive ulcerative lesions of the exocervix, or, rarely, necrotic cervicitis.
Women
have more extensive disease than men and a higher incidence of constitutional
symptoms and complications probably because of the larger surface area
involved. Wide areas of the female genitals may be covered with painful
erosions.
Extragenital lesions,
urinary retention, and aseptic meningitis occur in 20%, 15%, and 10% of
affected women, respectively. In contrast, aseptic meningitis is a rare
complication of primary genital herpes infection in men.
Herpetic
sacral radiculomyelitis, with urinary retention, neuralgias, and constipation,
can occur and, in men, impotence.
The presence of more extensive local involvement,
regional lymphadenopathy and fever generally distinguishes primary herpes
infection from recurrent disease.
Recurrent Genital Herpes
Epidemiology
Genital HSV infections can result in
both subclinical viral shedding and clinically evident recurrences. Virtually
all persons infected with HSV-2 will have recurrences, even if the initial
infection was subclinical or asymptomatic. The frequency of recurrences
correlates directly with the severity of the primary infection and tends to
decrease over the next several years. The rates of recurrence for genital HSV-2
infections also vary greatly among individuals and over time within the same
individual. HSV-2 infection results in recurrences in the genital area six
times more frequently than HSV-1 and average 3–4 times per year.
Clinical
features
Typical clinical recurrent genital
herpes begins with a prodrome of tenderness, burning, itching, or tingling
followed by clusters of small vesicles on
erythematous base which rupture to form erosions with scalloped borders in the genital area,
but it can occur anywhere in the perigenital region, including the abdomen,
groin, buttocks, and thighs. In men, lesions commonly occur on the glans or shaft of the penis. Similar lesions may
occur on the vulva, vagina or cervix and can cause distressingly painful
symptoms. Lesions
tend to recur in the same anatomic region, although not at exactly the same
site (as opposed to a fixed drug eruption). Without treatment, the lesions
usually heal in 7–10 days, compared to ~20 days for primary infections. Complications
are uncommon.
Course
Genital herpes is a
lifetime infection and recurrences are the rule. Seventy percent are
asymptomatic. Recurrence rates are high in those with an extended first episode
of infection, regardless of whether antiviral therapy is given. Chronic
suppressive therapy reduces shedding. Treatment of first-episode infection
prevents complications such as meningitis and radiculitis. Erythema multiforme
may complicate recurrences, occurring 1 to 2 weeks after an outbreak.
Management
of primary and recurrent genital herpes
For
treatment of primary and recurrent genital herpes, oral antivirals are the
agents of choice. With initiation within 24–48 hours of onset, acyclovir,
famciclovir, and valacyclovir reduce the duration of viral shedding, pain, and
time to healing for primary and recurrent genital herpes.
Chronic suppressive therapy with oral
antiviral agents is usually reserved for patients with six or more outbreaks
per year. In addition to decreasing the frequency of symptomatic outbreaks or
even eliminating them, suppressive therapy decreases asymptomatic viral
shedding by 95% and can thereby reduce transmission of genital herpes to a
susceptible partner. Cessation of therapy, even after
several years, may allow resumption of recurrences. Chronic suppressive
therapy is very safe and laboratory monitoring is not required.
Daily
suppressive therapy, together with regular
use of condoms
and avoidance of sexual activity during recurrences or when active lesions are
present, is therefore also recommended for individuals with genital herpes who
have a seronegative partner.
For patients with few or mildly
symptomatic recurrences, treatment is often not necessary. Counseling regarding
transmission risk is required. In patients with severe but infrequent
recurrences or in those who have severe psychological complications,
intermittent therapy may be useful.
To be effective, intermittent therapy
must be initiated at the earliest sign of an outbreak. The patient must be
given the medication before the recurrence, so treatment can be started by the
patient when the first symptoms appear.
Treatment of genital Herpes Simplex
|
Primary
herpes |
Acyclovir 200 mg five times/day for 7-10 days or until
resolution of symptoms |
|
|
Recurrent
herpes |
Acyclovir 400 mg three times/day for 5 days or until
lesions are healed |
|
|
Recurrent
herpes (long-term suppressive therapy) |
Acyclovir 400 mg twice a day |
Duration of therapy is controversial;
Some authorities will offer treatment
for 1 year and then
reassess the
need to resume it
Prevention
There is
significant interest in prevention of HSV disease. Between 70% and 80% of HSV
is transmitted during periods of asymptomatic viral shedding. Sexual abstinence
is the only method for absolute prevention of genital herpes, which can be
transmitted even with the use of condoms. In addition to antiviral therapy,
patient education regarding prevention of genital herpes transmission is
essential. There is currently no licensed vaccine available for HSV, although
several vaccines are under development and evaluation for prevention of HSV
infection and recurrences.
