Excessive sweating may be caused by hot
weather, exercise, or anxiety. In some
cases it is due to an infection,
or a nervous system
disorder. Usually, the disorder has no
known cause, and begins at puberty,
disappearing by the mid-20s or early 30s.
If hyperhidrosis is persistent and can-
not be controlled by
surgery may be considered to destroy
the nerve centres that control sweating.
Abnormally high blood
often due to failure
of the kidneys to excrete it.
Thickening of the skin's
outer layer due to an increased amount
The most common forms of
hyperkeratosis affect small, localized
areas of skin and include
A rare, inherited form affects
the whole of the soles and palms. The
term hyperkeratosis may also be used
to describe thickening of the nails.
that are characterized by high levels of
in the blood. Hyperlipidaemias may
be inherited or associated with another
disorder, such as
They may also be a result of use
are associated with
coronary artery disease
The signs depend on the type of hyper-
lipidaemia and may include fatty nodules
in the skin or over joints, and a white line
around the rim of the
. Treatment aims
to reduce blood lipid levels, usually by
a low-fat diet and
Commonly known as
longsightedness, hypermetropia is an
that initially causes
difficulty in seeing near objects and
then affects distance vision.
metropia tends to run in families.
Hypermetropia is caused by the eye
being too short from front to back,
which results in images not being clearly
focused on the
. The error is pre-
sent from birth, but symptoms generally
do not appear until later life because
the focusing power of
which compensates for hypermetropia,
declines with age.
lenses reinforce focusing power.
A type of
, also known as renal cell carcinoma.
tion of parathyroid hormone by the
that raises the calci-
um level in the blood (
by removing calcium from bones. This
may lead to bone disorders, such as
. To try to normalize the
high calcium level, the kidneys excrete
large amounts of calcium in the urine,
which can lead to the formation of kid-
ney stones (see
calculus, urinary tract
Hyperparathyroidism is most often
caused by a small noncancerous tumour
or more of the parathyroid glands. It
may also occur when the glands be-
come enlarged for no known reason. It
usually develops after age 40 and is
twice as common in women as in men.
Hyperparathyroidism may cause de-
pression and abdominal pain. However,
often the only symptoms are those
caused by kidney stones. If hypercal-
caemia is severe, there may be nausea,
tiredness, excessive urination, confu-
sion, and muscle weakness.