Bronchial Asthma is characterized by widespread narrowing of the bronchial airways, the severity of which can change over short periods of time (either spontaneously or under treatment) and leads to cough, wheezing, and difficulty in breathing.

Cardiac Asthma occurs in left ventricular heart failure. It must be distinguished from bronchial asthma because the treatment is different.

Bronchial asthma can follow from 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 people (i.e. those with hereditary predisposition to hypersensitivity to certain allergens) may be accompanied by other manifestations of hypersensitivity, such as hay-fever and dermatitis. However it is not only first experienced at a young age; onset can occur in adulthood, even in 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.

(a) Acute Bronchitis

Acute bronchitis caused by viruses or bacteria.

• Coughing
• The production of mucpurulent sputum.
• Narrowing of the bronchi due to spasmodic contraction.

(b) 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.

(a) 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.

(b) 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.

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.

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

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.

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, 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 spitting 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.