Respiratory Diseases and Disorders

The following are diseases and disorders of the respiratory system:

Bronchitis

Inflammation of the bronchi. Symptom - thick yellowish green sputum showing over production of mucus due to an infection. Chronic bronchitis is principally caused by cigarette smoking (also pollution).

Emphysema ("blown up" or "full of air")

Alveolar walls loose their elasticity and remain filled with air during expiration.

1st symptom is reduced forced expiratory volume. Alveoli then merge thus reducing surface area. Lungs end up being permanently inflated leading to an increased chest cage size with the individual working harder to exhale. Damaged alveoli reduce oxygen exchange. Alveolar wall becomes replaced by connective tissue therefore CO₂ cannot escape, the pH falls and this damages brain cells. This leads to respiratory centre being less active, therefore the breathing rate slows.

Causes - long term irritation by air pollution, industrial dust, cigarette smoke. Progressive deterioration can be prevented by eliminating the harmful stimuli.

Pleurisy

Inflammation of the pleural membrane causing friction during breathing. This can be painful when the swollen membranes rub against each other.

Pneumonia

Acute infection or inflammation of the alveoli. The alveolar Sacs fill with fluid thus reducing air intake and gaseous exchange. Most common cause in pneumococcus but may be caused by fungi & viruses including the influenza virus.

Tuberculosis

Inflammation produced by Mycobacterium tuberculosis. Usually affect the lungs and pleurae. Bacteria destroy the lung tissue which is replaced by fibrous connective tissue. This reduces elasticity etc.

TB is spread by inhalation and is associated with crowded poorly lit housing (they are destroyed by sunlight). Rest, sunlight and good diet are vital parts of treatment.

Asthma

Where smooth muscles on the (smaller) bronchiole walls go into spasm (because there is no supporting cartilage). This closes of the airways therefore making it difficult to exhale. The mucus membranes that line the respiratory passageways become irritated and secrete excess mucous which block the passageways and worsens the attack.

It may be due to allergic reaction particularly to airborne dust, bacterial protein (even commensal that line the passages of the throat etc. It may be psychosomatic. Symptoms are attacks of wheezing and difficulty breathing.

Rhinitis

Chronic or acute inflammation of the mucous membranes of the nose & sinuses. Caused by colds, hay fever etc. Causes headaches & facial pain.

Hay Fever

Over sensitive immune response to pollen. May cause sneezing, rhinorhea, swelling, itching etc.

Sinusitis

Inflammation of sinuses often caused by respiratory infection.

Stress

Hyperventilation.