farmer’s lungAn occupational disease
affecting the lungs of farm workers.
Farmer’s lung is a type of allergic alveo-
litis, in which affected people develop
hypersensitivityto certain moulds that
grow on hay, grain, or straw. Symptoms
develop about 6 hours after exposure
to dust containing fungal spores and
include shortness of breath, headache,
fever, and muscle aches. In acute at-
tacks, the symptoms last for about a day.
Repeated exposure to spores may lead
to a chronic form of the disease, caus-
ing permanent scarring of lung tissues.
Diagnosis of farmer’s lung may involve
a chest X-ray,pulmonary function tests,
and blood testsfor a specific antibody.
Corticosteroid drugswill relieve the symp-
toms. Further exposure to the spores of
the fungus should be avoided. (See also
fibrosing alveolitis.)
fasciaFibrous connective tissuethat sur-
rounds many structures in the body.
One layer of the tissue, known as the
superficial fascia, envelops the entire
body just beneath the skin. Another
layer, the deep fascia, encloses muscles,
forming a sheath for individual muscles
and separating them into groups; it also
holds in place soft organs such as the
kidneys. Thick fascia in the palm of the
hand and sole of the foot have a cush-
ioning, protective function.
fasciculationSpontaneous, irregular, and
usually continual contractions of a mus-
cle that is apparently at rest. Unlike the
contractions of fibrillation, fasciculation
is visible through the skin.
Minor fasciculation, such as that which
occurs in the eyelids, is common and is
no cause for concern. However, persis-
tent fasciculation with weakness in the
affected muscle indicates damage to
nerve cells in the spine that control the
muscle or nerve fibres that connect
the spinal nerves to the muscle; motor
neuron diseaseis one such disorder.
fasciitisInflammation of a layer of fas-
cia(fibrous connective tissue), causing
pain and tenderness. Fasciitis is usually
the result of straining or injuring the
fascia surrounding a muscle; it most
commonly affects the sole of the foot.
Fasciitis may occur in people who suffer
from ankylosing spondylitis(a rheumaticdisorder affecting the spine) or Reiter’s
syndrome(inflammation of the urethra,
conjunctivitis, and arthritis).
Treatment involves resting the affected
area and protecting it from pressure. In
some cases, a local injection of a cor-
ticosteroid drugis given. If fasciitis is
part of a widespread disorder of the
joints, treatment of this condition will
generally improve symptoms.
fascioliasisA disease affecting the liver
and bile ducts that is caused by infesta-
tion with the liver flukespecies FASCIOLA
HEPATICA.
fasciotomyAn operation to relieve pres-
sure on muscles by making an incision
in the fascia(fibrous connective tissue)
that surrounds them. The operation is
usually performed to treat compartment
syndrome, a painful condition in which
constriction of a group of muscles causes
obstruction of blood flow. Fasciotomy is
also sometimes performed as a surgical
emergency after an injury has resulted
in muscle swelling or bleeding within a
muscle compartment.
fastingAbstaining from all food and
drinking only water. In temperate con-
ditions and at moderate levels of physical
activity, a person can survive on water
alone for more than 2 months; however,
without food or drink, death usually oc-
curs within about 10 days.
About 6 hours after the last meal, the
body starts to use glycogen (a carbohy-
drate stored in the liver and muscles).
This continues for about 24 hours, after
which the body obtains energy from
stored fat and by breaking down protein
in the muscles. If fasting continues, the
body’s metabolismslows down to con-
serve energy, and the fat and protein
stores are consumed more slowly.
In the initial stages of fasting, weight
loss is rapid. Later it slows down, be-
cause metabolism slows down and the
body starts to conserve its salt supply,
which causes water retention. In pro-
longed fasting, the ability to digest food
may be impaired because the stomach
stops secreting digestive juices. Pro-
longed fasting also halts production of
sex hormones, causing amenorrhoea(ab-
sence of menstruation) in women.
fatigueSee tiredness.FARMER’S LUNG FATIGUEF