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(Kartagener's Syndrome, Primary Ciliary Dyskinesia)
Tell Me About Immotile Cilia Syndrome
This web page will tell you about lung anatomy
and what Immotile Cilia Syndrome is, as well as what the common
symptoms are.
What is Immotile Cilia Syndrome?
Cilia are tiny hair-like structures on the surface
of the lining of the respiratory tract. Unlike hair, cilia can move,
and the body uses cilia primarily to transport mucous out of the
respiratory tract. Immotile Cilia Syndrome (or Primary Ciliary
Dyskinesia or Kartagener's Syndrome) is a chronic lung
disease which occurs when the cilia are unable to move. This causes
mucous to become stuck in various parts of the respiratory tract,
leading to symptoms.
Immotile Cilia Syndrome is a very rare syndrome,
with an incidence of about 1 in 30,000 persons. Because it
is so rare, large studies on this condition have not been performed.
Much of the treatment of Immotile Cilia Syndrome is based on the
treatment of Cystic Fibrosis, which is commoner (1 in
2,000 persons) and has some similar features.
A Tale of Many Names
Immotile Cilia Syndrome, as the
name implies, describes a disease that occurs when cilia in the
body are unable to move. Recent research has shown that, in some
forms of Immotile Cilia Syndrome, cilia can move, but are unable
to beat effectively. Because of this, some experts have suggested
that the name be changed to Primary Ciliary Dyskinesia
(dyskinesia means "abnormal movement"). In about
1/2 of patients with Immotile Cilia Syndrome, the heart and other
organs are located on the right side, rather than the left. When
patients with Immotile Cilia Syndrome have the heart on the right
side, they are said to have Kartagener's
Syndrome.
It is important to
realize that Immotile Cilia Syndrome, Primary Ciliary Dyskinesia,
and Kartagener's Syndrome all refer to exactly the same condition,
with the same symptoms and needing the same treatments (except that
all patients with Kartagener's Syndrome also have the heart on the
right side). While the term "Primary Ciliary Dyskinesia"
is newer and more technically correct, the term "Immotile Cilia
Syndrome" is more commonly used, and will be used throughout
this Web site.
Incidentally, having the heart on the right side
is known as dextrocardia. Having all the organs on the
opposite side from the usual (for example, having the liver on the
left side and the stomach on the right side of the body) is known
as situs inversus.
A Little Anatomy
The lungs consist of airways (also known as bronchial
tubes, or bronchi), and air
sacs (also known as alveoli). The purpose of the
airways is to allow fresh air to travel into the air sacs, and to
allow spent air to travel out of the lungs. Blood vessels move blood
close to the alveoli, so that fresh oxygen
inhaled from the atmosphere can move into the blood. In addition,
waste gas (or carbon dioxide)
travels from the blood into the alveoli, to be
later exhaled into the atmosphere. Other blood vessels
move the blood, newly-loaded with oxygen and relatively-free of
waste gas away from the alveoli, to travel to the rest of the body.
The bronchial tubes have tiny bands of muscle,
which encircle them. When air containing noxious gases or fumes
(such as cigarette smoke or polluted air) is inhaled, these bands
of muscle can constrict, narrowing the airways and reducing the
amount of irritating gas entering the lungs. This is known as bronchospasm.
When irritating gases enter the lungs, the inner lining of the bronchial
tubes produce mucous, to trap any irritating particles. In
addition, the inner lining of the bronchial tubes contains special
cells, called inflammatory cells, which release chemicals after
exposure to irritants.
What's Inflammation?
Inflammation is the body's way of dealing with
physical injuries, such as injury to the lining of the bronchial
tubes caused by harmful gases. Inflammation is produced when inflammatory cells in the area release special chemicals, known as inflammatory
chemicals. These chemicals:
- cause swelling of the tissues;
- promote mucous secretion (in airways);
- help destroy any bacteria which have entered the tissues (the
chemicals which destroy bacteria can also cause further tissue
damage in the area);
- tell the body to send more inflammatory cells into the area;
- promote healing of the damaged area.
Everyday examples of inflammation which everyone's
familiar with include the redness, pain, and swelling which occur
after a minor burn, and when a splinter is not removed promptly.
Mucous Clearance
Small amounts of mucous are normally produced in
the bronchial tubes to trap soot, bacteria, and other small
particles we all breathe in every day, and larger amounts of mucous
are produced when the bronchial tubes are inflammed (for example,
after smoke or polluted air exposure, or during a respiratory infection).
The cells lining the bronchial tubes are covered by tiny, moving
hairs called cilia, which beat in the direction
of the mouth. 
The beating of these cilia moves mucous up the bronchial tubes and
windpipe up to the mouth, where the mucous is either swallowed or,
occasionally, coughed out.
The passages of the nose, sinuses, and Eustachian
tube (the tube connecting the middle ear with the inside of the
throat) are lined by tissues which are very similar to the tissues
of the bronchial tubes, and the cells lining these passages are
also covered by cilia.
Mucous is moved by the cilia in these passages:
- Out of the sinuses and into the nose;
- Out of the nose and into the throat; and
- Out of the Eustachian Tube(s) and into the throat.
The Structure of Cilia
Cilia can just barely be seen with the strongest
regular microscopes. To see the parts that make up individual cilia,
an electron microscope, providing magnification of 60,000X or greater,
is needed.
Cilia are made up of even tinier tubes, called
microtubules. All cilia contain 9 outer pairs of microtubules, and
2 central single tubules. From each outer pair of microtubules,
a pair of dynein "arms" reach towards
the next pair of microtubules. The dynein arms actually grab the
adjacent pair of microtubules in a specific order, which causes
the cilia to bend. Radial spokes extend from each outer pair of
microtubules towards the inner central tubules. Nexin links also
join each outer pair of microtubules with the adjacent outer pair.
Radial spokes and nexin links help stabilize the cilia's structure.
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