alpha 1 -antitrypsin deficiencyA rare
genetic disorderin which a person is
missing the enzyme alpha 1 -antitrypsin,
which protects the body from damage
by other enzymes. The disease mainly
affects tissues in the lungs, resulting in
emphysema, and the liver, causing cir-
rhosis. The effects of alpha 1 -antitrypsin
deficiency may not become apparent
until after the age of 30. There is no
cure, but symptoms can be relieved by
drug treatment. In severe cases, a liver
transplantmay be a possibility.
alpha-blocker drugsA group of drugs
used to treat hypertension(high blood
pressure) and urinary symptoms due to
enlargement of the prostate gland.
Alpha-blockers are also used to treat
urinary retention caused by an enlarged
prostate gland (see prostate,enlarged).
Side effects of the drugs may include
dizziness and fatigue due to a sudden
drop in blood pressure, nausea, dry
mouth, and drowsiness.
alpha-fetoproteinA protein that is
produced in the liver and gastrointes-
tinal tract of the fetus and by some
abnormal tissues in adults.
Alpha-fetoprotein (AFP) can be meas-
ured in the maternal blood from the
latter part of the 1st trimester of preg-
nancy, and its concentration rises
between the 15th and 20th weeks.
Raised levels of AFP are associated with
fetalneural tube defects, such as spina
bifidaor anencephaly,and certain kid-
ney abnormalities. High levels of AFP
also occur in multiple pregnancies (see
pregnancy,multiple) and threatened or
actual miscarriage. AFP levels may be
unusually low if the fetus has Down’s
syndrome. For this reason, measure-
ment of blood AFP is included in blood
tests, which are used to screen preg-
nant women for an increased risk of
Down’s syndrome.
AFP levels are commonly raised in
adults with hepatoma (see liver cancer),
cancerous teratomaof the testes or
ovaries, or cancer of the pancreas,
stomach, or lung. For this reason, AFP
is known as a tumour marker. AFP levels
can be used to monitor the results of
treatment of certain cancers; increasing
levels after surgery or chemotherapy
may indicate tumour recurrence. How-
ever, AFP levels are also raised in some
noncancerous conditions, including viral
and alcoholic hepatitisand cirrhosis.
alprazolamA benzodiazepine drug used
in the treatment of anxiety, panic attacks,
and phobias.
alprostadilA prostaglandin drugused,
prior to surgery, to minimize the effects
of congenital heart defects in newborn
babies. Alprostadil is also used as a
treatment for impotence. It is adminis-
tered by self-injection into the penis or
as a gel introduced into the urethrato
produce an erection.
alternative medicineAny medical sys-
tem based on a theory of disease or
method of treatment other than the
orthodox science of Western medicine.
(See also complementary medicine.)
altitude sicknessSee mountain sickness.
aluminiumA light, metallic element
found in bauxite and various other min-
erals. Aluminium compounds are used
in antacidmedications and in antiper-
spirants. Most of the aluminium taken
into the body is excreted. Excessive
amounts are toxic and are stored in the
lungs, brain, liver, and thyroid gland,
where they may result in organ damage.
Certain industrial processes give off
fumes containing aluminium into the
air. These fumes can cause fibrosisof
lung tissue. Drugs that contain alumin-
ium may interfere with the absorption
of other drugs and, therefore, should
not be taken at the same time.
alveolectomySee alveoloplasty.
alveolitisInflammation and thickening
of the walls of the alveoli (tiny air sacs)
in the lungs. Alveolitis reduces the elas-
ticity, and therefore the efficiency, of the
lungs. It is most commonly due to an
allergic reaction to inhaled dust of ani-
mal or plant origin, as in farmer’s lung,
bagassosis, and pigeon fancier’s lung
(due to particles from bird droppings).
Fibrosing alveolitis is an autoimmune
disorder. In some cases, it occurs with
other autoimmune disorders such as
rheumatoid arthritis or systemic lupus
erythematosus. Radiation alveolitis is
caused by irradiation of the lungs and
may occur as a rare complication of
radiotherapyfor lung or breast cancer.ALPHA 1 -ANTITRYPSIN DEFICIENCY ALVEOLITIS
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