Page 303 - Review of Medical Microbiology and Immunology ( PDFDrive )

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PART IV Clinical Virology
(4) Encephalitis caused by HSV-1 is characterized by a
necrotic lesion in one temporal lobe. Fever, headache, vom-
iting, seizures, and altered mental status are typical clinical
features. The onset may be acute or protracted over several
days. The disease occurs as a result of either a primary
infection or a recurrence. Magnetic resonance imaging
often reveals the lesion. Examination of the spinal fluid
typically shows a moderate increase of lymphocytes, a
moderate elevation in the amount of protein, and a normal
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amount of glucose. HSV-1 encephalitis has a high mortality
rate and causes severe neurologic sequelae in those who
survive.
(5) Herpetic whitlow is a pustular lesion of the skin of
the finger or hand. It can occur in medical personnel as a
result of contact with patient’s lesions.
(6) Herpes gladiatorum, as the name implies, occurs in
wrestlers and others who have close body contact. It is
caused primarily by HSV-1 and is characterized by vesicu-
lar lesions on the head, neck, and trunk.
(7) Eczema herpeticum (Kaposi’s varicelliform erup-
tion) is an infection of the skin of a patient with atopic
dermatitis. Vesicular lesions are seen at the site of the atopic
dermatitis (eczema). Most cases occur in children.
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mebooksfree.com mebooksfree.com mebooksfree.com FIGURE 37–4 Herpes genitalis—note vesicles on shaft of mebooksfree.com
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(8) Disseminated infections, such as esophagitis and
pneumonia, occur in immunocompromised patients with
depressed T-cell function.
penis caused by herpes simplex virus type 2. (Used with permission from
HSV-2 causes several diseases, both primary and
Jack Resneck, Sr., MD.)
recurrent:
(1) Genital herpes is characterized by painful vesicular
section on women with either active lesions or positive
lesions of the male and female genitals and anal area
viral cultures. Both HSV-1 and HSV-2 can cause severe
(Figure 37–4). The lesions are more severe and protracted
neonatal infections that are acquired after birth from car-
in primary disease than in recurrences. Primary infections
are associated with fever and inguinal adenopathy.
neonatal infections, neither HSV-1 nor HSV-2 causes con-
Many infections are asymptomatic (i.e., many people
genital abnormalities to any significant degree.
have antibody to HSV-2 but have no history of disease). riers handling the child. Despite their association with
mebooksfree.com mebooksfree.com mebooksfree.com virus produced during a primary infection is greater than mebooksfree.com
Serious neonatal infection is more likely to occur when
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Asymptomatic infections occur in both men (in the pros-
the mother is experiencing a primary herpes infection than
tate or urethra) and women (in the cervix). Shedding of
a recurrent infection for two reasons: (1) the amount of
virus from those with an asymptomatic infection occurs
sporadically and can be a source of infection of other
during a secondary infection, and (2) mothers who have
individuals.
been previously infected can pass IgG across the placenta,
Approximately 80% to 90% of herpes genitalis cases are
which can protect the neonate from serious disseminated
caused by HSV-2. The remainder are caused by HSV-1 as a
infection.
result of oral–genital contact. The clinical importance of
(3) Aseptic meningitis caused by HSV-2 is usually a
this is that suppressive chemoprophylaxis for HSV-2 lesions
mild, self-limited disease with few sequelae.
should be considered because lesions caused by HSV-2 are
more likely to recur than lesions caused by HSV-1.
Both HSV-1 and HSV-2 infections are associated with
(2) Neonatal herpes originates chiefly from contact
with vesicular lesions within the birth canal. In some cases, erythema multiforme. The rash of erythema multiforme
appears as a central red area surrounded by a ring of nor-
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mebooksfree.com mebooksfree.com mebooksfree.com rash is thought to be an immune-mediated reaction to the mebooksfree.com
although there are no visible lesions, HSV-2 is shed into the
mal skin outside of which is a red ring (“target” or “bull’s
eye” lesion). The lesions are typically macular or papular
birth canal (asymptomatic shedding) and can infect the
child during birth. Neonatal herpes varies from severe dis-
and occur symmetrically on the trunk, hands, and feet. The
ease (e.g., disseminated lesions or encephalitis) to milder
local lesions (skin, eye, mouth) to asymptomatic infection.
presence of HSV antigens. Acyclovir is useful in preventing
recurrent episodes of erythema multiforme, probably by
Neonatal disease may be prevented by performing cesarean
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