Conditions affecting the Respiratory System

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.

May 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 and must be distinguished from bronchial asthma, as the treatment is quite different.

Bronchitis

Acute Bronchitis:

Is 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.

The disease is particularly prevalent in Britain in association 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.

Severe 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 the affected tissues 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.

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.

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.

Pneumonia

Inflammation of the lung caused by bacteria, in which the air sacs (alveoli) become filled with inflammatory cells and the lung becomes solid.

Rhinitis

Inflammation of the mucous membrane of the nose.

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

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.