Term
|
Definition |
Cause
|
Effect (Symptoms)
|
Asthma |
Bronchial Asthma is the condition of
subjects with widespread narrowing of the bronchial
airways, which
changes in severity over short periods of time (either
spontaneously or under treatment) and leads to cough,
wheezing, and difficulty in breathing. |
Asthma can be precipitated by exposure to one
or more of a wide range of stimuli, including allergens,
drugs (such as aspirin and other NSAIDs and beta blockers),
exertion, emotion, infections, and air pollution.The
onset of asthma is usually early in life and in atopic
subjects may be accompanied by other manifestations of
hypersensitivity, such as hay-fever and dermatitis; however
the onset may be delayed into adulthood or even middle
or old age. |
Treatment is with bronchodilators,
with or without corticosteroids, usually administered
via
aerosol or dyr-powder inhalers, or – if the
condition is more severe – via a nebulizer. Oral
corticosteroids are reserved for patients who fail
to respond adequately
to these measures. Severe asthmatic attacks may need
large doses of corticosteroids.Avoidance of known allergens,
especially the house dust mite, allergens arising from
domestic pets, and food additives, will help to reduce
the frequency of attacks, as will the discouragement
of smoking. |
|
Cardiac Asthma occurs
in left ventricular heart failure. This must be distinguished
from bronchial
asthma because the treatment is different. |
See also asthma in the news. |
Bronchitis
|
Acute Bronchitis:
|
Acute bronchitis caused by viruses or bacteria.
|
- Coughing
- The production of mucpurulent sputum.
- Narrowing of the bronchi due to spasmodic
contraction.
|
| |
Chronic Bronchitis:
Is not primarily an inflammatory condition, although it is frequently complicated
by acute infections.
|
Chronic bronchitis in Britain
has been associated with cigarette smoking, air pollution,
and emphysema.
|
- The patient coughs up excessive mucus secreted by enlarged bronchial mucus glands.
- The bronchospasm cannot always be relieved by bronchodilator drugs.
|
|
Emphysema
|
Pulmonary emphysema:
The air sacs (alveoli)
of the lungs are enlarged and damaged, which reduces
the surface area for the exchange of oxygen and carbon
dioxide. |
Normal lung tissue contains:
Over-expansion of aveloar sacs leads to:
- Loss of elasticity
- Loss of surface area
- Loss of lung capacity
- Insufficient take-up of oxygen
It is particularly common in men
in Britain and is associated with chronic bronchitis,
smoking, and advancing age. |
Severe pulmonary emphysema causes breathlessness / severe
breathing difficulty, which is made worse by infections. |
| |
Surgical emphysema: |
Air may escape into the tissues of the
chest and neck from leaks in the lungs and oesophagus;
occasionally air escapes into other tissues during
surgery, and bacteria may form gas in soft tissues.
The presence of gas or air gives the affected tissues
a characteristic crackling feeling to the touch, and
it may be visible on X-rays. It is easily absorbed
once the leak or production is stopped. |
The presence of gas or air gives tissues affected by surgical emphysema a characteristic crackling feeling
to the touch. |
Hay Fever |
A form of allergy due to the pollen
of grasses, trees, and other plants, characterized
by inflammation of the lining of the nose and sometimes
of the conjunctiva. |
Hay fever is generally attributed to a reaction to the pollens of grasses, trees, and other
plants. |
The symptoms of sneezing, running or
blocked nose, and watering eyes are due to histamine
release and often respond to treatment with antihistamines. If
the allergen is identified it may be possible to undertake
desensitization. |
See also allergies in the news. |
Pleurisy
|
Inflammation of the pleura. |
Often due to pneumonia in the underlying
lung. The normally shiny and slippery pleural
surfaces lose their sheen and become slightly
sticky, so that there is pain on deep breathing.
Pleurisy is always
associated with some other disease in the lung, chest
wall, diaphragm, or abdomen. |
- Pain on deep breathing
- A characteristic ‘rub’ can
be heard through a stethoscope
|
|
Pneumonia
|
Inflammation of the lung caused by bacteria,
in which the air sacs (alveoli) become filled with
inflammatory cells and the lung becomes solid. |
Bacteria
Pneumonias may be classified in different ways:
- According to X-ray appearance
- According to the infecting organism
- According to the clinical environmental circumstances under which the infection is acquired (e.g. ‘community-acquired pneumonia’, ‘hospital-acquired (nosocomial) pneumonia’)
|
Symptoms include those of any infection:
- Fever, Malaise, Headaches etc., together with
- Cough and chest pain
Treatment:
Appropriate antibiotic therapy,
based on the clinical situation and on microbiological
studies, results in complete recovery in the majority
of patients. |
Rhinitis |
Inflammation of the mucous membrane
of the nose. |
Rhinitis can be caused by:
- Virus infection
(acute rhinitis)
- Allergic reaction
(allergic rhinitis) |
In atrophic rhinitis
the mucous membrane becomes thinned and
fragile.
In perennial (or vasomotor)
rhinitis there is overgrowth of, and increased secretion
by, the membrane. |
|
Tuberculosis
|
Tuberculosis, also known as simply 'TB', is an infectious disease caused by the
bacillus Mycobacterium tuberculosis and characterized
by the formation of nodular lesions (tubercles) in
the tissues. |
Bacillus inhaled into the lungs:
In pulmonary tuberculosis
– formerly known as consumption
and pthisis (wasting –
the bacillus is inhaled into the lungs where
it sets up a primary tubercle and spreads
to the nearest lymph nodes (the primary
complex). Natural immune defences
may heal it at this stage; alternatively
the disease may smoulder for months or years
and fluctuate with the patient’s resistance.
Many people become infected but show no
symptoms. Others develop a chronic infection
and can transmit the bacillus by coughing
and sneezing.
Bacillus entering by mouth (usually in
infected cow’s milk):
Set up a primary
complex in the abdominal lymph nodes, leading to peritonitis,
and sometimes spread to other organs, joints, and bones.
|
Symptoms of the active disease include
fever, night sweats, weight loss, and the spitting
of blood. In some cases the bacilli spread from the
lungs to the bloodstream, setting up millions of tiny
tubercles throughout the body (military tuberculosis),
or migrate to the meninges to cause tuberculous meningitis.
Treatment:
Tuberculosis
is curable by various combinations of antibiotics.
Preventative measures in the UK include the detection
of cases by X-ray screening of vunerable populations
and inoculation with BCG vaccine of those with no
immunity to the disease. |
See also tuberculosis in the news. |
