HERPES ZOSTER
H
cells in the facial area. In many people,
the virus is periodically reactivated, caus-
ing
c o l d s o r e s
that invariably erupt in the
same site (usually around the lips).
Sometimes the virus can infect a fin-
ger after touching a cold sore, causing a
painful eruption called a
h e r p e t i c w h i t -
l o w .
HSV
1
may also produce eczema
herpeticum (an extensive rash of skin
blisters) in a person with a pre-existing
skin disorder, such as
e c z e m a .
Eczema
herpeticum may require hospital admis-
sion. If the virus gets into an eye it may
cause
c o n j u n c t i v i t i s ,
w hich usually lasts
only a few days; more seriously, it may
cause a
c o r n e a l u l c e r
.
Rarely, HSV
1
spreads to the brain,
leading to
e n c e p h a l i t i s .
The virus may
cause
a
potentially
fatal
generalized
infection in a person with an
i m m u n o -
d e f i c i e n c y d i s o r d e r
or in someone taking
i m m u n o s u p p r e s s a n t d r u g s .
Type 2 virus HSV
2
is the usual cause of
sexually transmitted genital herpes (see
h e r p e s , g e n i t a l ) ,
in w hich painful blis-
ters erupt in the genital area. In some
people, the blisters tend to recur.
TREATMENT
Treatment of herpes simplex depends
on its type, site, and severity of symp-
toms.
A n t i v i r a l d r u g s ,
such as
a c i c l o v i r ,
may be helpful, particularly if used
early in an infection.
herpes zoster
An infection of the
n e r v e s
supplying cer-
tain skin areas that is characterized by a
painful rash of small crusting blisters.
Also called shingles, herpes zoster is
especially common among older people.
TYPES
Herpes zoster usually affects only one
side of the body, and follows the path of
a nerve. It commonly develops on a
strip of skin over the ribs, although the
rash may also appear on the neck, arm,
or lower part of the body. Sometimes
the infection involves the face and eye;
this form of the disorder is called her-
pes zoster ophthalmicus.
CAUSES
Herpes zoster is caused by the
v a r i -
c e l l a - z o s t e r
virus,
w hich
also
causes
c h i c k e n p o x .
After an attack of chicken-
pox, some of the viruses survive and lie
dormant for many years in the nerve
cells near the spinal cord. In some peo-
ple, a decline in the efficiency of the
i m m u n e s y s t e m
- especially in old age -
because
of disease
or
severe
stress,
allows the viruses to re-emerge and
cause herpes zoster. The disorder is also
Example of herpes zoster
An extensive rash of blisters has spread around
one side of the body, just under the ribs, and on to
the front of the abdomen.
common in people whose immune sys-
tem is weakened by stress or by certain
drugs, such as
c o r t i c o s t e r o i d d r u g s
or
a n t i c a n c e r d r u g s .
SYMPTOMS
The first indication of herpes zoster is
excessive sensitivity in the skin, fol-
lowed by pain, w hich is often severe.
The infection can be difficult to diag-
nose at this stage and may be mistaken
for a different condition; for example,
pain in the chest wall may be mistaken
for angina pectoris. After about five
days, the rash appears as small, raised,
red spots that soon turn into blisters.
W ithin a few days, the blisters dry, flat-
ten, and develop crusts. Over the next
two weeks, the crusts drop off, some-
times leaving small pitted scars.
The most serious feature of herpes
zoster is pain after the attack, known as
postherpetic neuralgia,
w hich
affects
about a third of all infected people. This
pain is caused by nerve damage, and
may last for months or years. Herpes
zoster ophthalmicus may cause a
c o r n e a l
u l c e r
or
u v e i t i s
(inflammation of the part
of the eye known as the uvea).
TREATMENT
If treatment is begun soon after the rash
appears,
a n t i v i r a l d r u g s ,
such as
a c i c l o v i r
,
w ill reduce the severity of the symptoms
and minimize nerve damage.
A n a l g e s i c
d r u g s
(painkillers) may also be helpful
in relieving pain. If
p o s t h e r p e t i c n e u r a l g i a
is a problem,
a n t i c o n v u l s a n t d r u g s ,
such
as
g a b a p e n t i n ,
may be helpful.
herpetic whitlow
A painful swelling on the finger caused
by infection with the
h e r p e s s i m p l e x
virus. (See also
w h i t l o w . )
heterosexuality
Sexual attraction of an individual to
members of the opposite sex. (See also
b i s e x u a l i t y ; h o m o s e x u a l i t y . )
heterozygote
A term used to describe a person whose
cells contain two different
a l l e l e s
(forms
of a particular gene) controlling a spec-
ified inherited trait. A
h o m o z y g o t e
has
identical alleles controlling that trait.
(See also
i n h e r i t a n c e ; g e n e t i c d i s o r d e r s . )
hexachlorophene
An
a n t i b a c t e r i a l d r u g
used in dusting
powder form to prevent
s t a p h y l o c o c c a l
i n f e c t i o n s
in newborns, and to prevent
and treat
b e d s o r e s
.
hiatus hernia
A condition in w hich part of the
s t o m -
a c h
protrudes upwards into the chest
through an opening in the
d i a p h r a g m
called the hiatus, w hich is normally
occupied by the
o e s o p h a g u s .
The cause
is unknown, but hiatus hernia is more
common in
obese
people.
In some
cases, it is present at birth.
Many people have no symptoms. In
some people, however, the hiatus hernia
impairs the efficiency of the oesophageal
sphincter, the muscle at the junction
between the oesophagus and the stom-
ach. Weakness in this muscle allows
a c i d
r e f l u x
as the stomach acid escapes into
the oesophagus. This problem may lead
to
o e s o p h a g i t i s
(inflammation
of the
oesophagus) or to
h e a r t b u r n ,
which pro-
duces pain or discomfort in the centre of
the chest.
A n t a c i d d r u g s ,
H 2 receptor antagonists,
or proton pump inhibitors (all types of
u l c e r - h e a l i n g
d r u g )
may
be
given
to
reduce stomach acidity. In severe cases,
surgery may be required to return the
stomach to its normal position and to
Common type of hiatus hernia
Part of the stomach slides into the chest through
the oesophageal hiatus (opening).
380
previous page 379 BMA A Z Family Medical Encyclopedia   2004 read online next page 381 BMA A Z Family Medical Encyclopedia   2004 read online Home Toggle text on/off