Pathophysiology is the study of what is abnormal, or what causes
normal physiological processes to be disturbed. Asthma is a chronic
inflammatory problem of the lungs and bronchioles which is characterized
by reversible bronchospasm that often result from an exaggerated
response to a variety of stimuli. This is the pathophysiological
response which the lungs take when assaulted by an allergen.
What
does all this mean? Well in the first place it means that asthma is not
all in the mind and that it cannot be outgrown. It also means that it is
a serious disease but is that you cannot catch it from someone else who
has it. The pathophysiological changes resulted inflammation and
symptoms such as coughing, wheezing and shortness of breath.
There
are actually two types of asthma-extrinsic and intrinsic. An asthmatic
who suffers from extrinsic asthma will have difficulty with allergic and
immune responses. These individuals are often classified as being
atopic, meaning that they have difficulty with IgE responses.
Individuals who have asthmatic attacks from intrinsic factors means that
they do not have an immune response but rather an allergic response to
either aspirin or specific types of infections.
The more common of
the two are those individuals who suffer from extrinsic asthma, or that
which is immune mediated. In these cases the lungs of the individual
becomes inflamed and the bronchial tubes become hyper responsive to
allergens. The inflammation in the airway is an important part of the
pathology and the underlying process which derives and maintains the
inflammatory process.
The inflammation will activate the release
of mast cells, eosinophils and macrophages in the airway. These
substances increase the amount of mucus secretion present in the
airways.
Therefore an individual with asthma struggles with two
individual responses in the bronchi and bronchioles which results in
decreased air exchange in the lungs, coughing, wheezing and shortness of
breath. In the first instance the lungs become inflamed or swollen from
the allergic response to an inhaled substance. The inflammation alone
is enough to cause difficulty breathing, wheezing and shortness of
breath.
Combined with the inflammation is the increased mucus
production caused by the body's response to the allergen inside the
lungs. This increased mucus production also causes shortness of breath
and wheezing but it also induces coughing to clear the mucus.
This
complex interaction between inflammatory cells, mediators and tissues
in the airway cause injury to the epithelium and prolonged contraction
of the smooth muscle. The lungs continue to secrete mucus, swell and
change the involuntary control of breathing. These inflamed airways
become more narrow and obstructed which causes hyper-responsiveness and
results in narrowing when the stimulus is introduced.
Individuals
who suffer from extrinsic asthma can be triggered by a viral respiratory
infections, pollen or mold, tobacco smoke, cold air or even exercise.
Most individuals must determine their particular triggers in order to
avoid them and thus prevent an asthmatic attack.
This airway
obstruction can develop suddenly or gradually and will cause very real
physical symptoms that can range from mild to life-threatening. Although
stress has been known to increase the severity of the symptoms, asthma
is not a condition which is psychologically based. But, like all other
physical conditions, stress will increase the severity of the body's
reaction to the disease.
