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Asthma

Asthma is an immunological disease which causes difficulty in breathing. In this disease, the bronchioles in the lungs are narrowed by inflammation and spasm of the lining of the airway wall. A person with asthma may experience wheeze, shortness of breath and poor exercise tolerance.

Table of contents
1 Pathology
2 Symptoms
3 Signs
4 Diagnosis
5 Treatment

Pathology

Pathogenesis

Symptoms

The cardinal symptom of asthma is wheeze, indicating airway obstruction. Cough, sometimes with clear sputum may be present. Typically the symptoms are very variable, often with rapid onset, and associated with the triggers listed above. Symptoms are often worse during the night or on waking. Increasing airway obstruction will cause shortness of breath.

Signs

"Signs" (what a physician finds on examination) are wheeze, rapid breathing, expiratory phase of breathing longer than inspiratory, indrawing of tissues between ribs and above sternum & clavicles, overinflation of the chest and rhonchi (wheezy noises heard with a stethoscope). In severe attacks the asthma sufferer may be cyanosed (blue) and can lose consciousness. Between attacks a person with asthma may show no signs at all.

Diagnosis

In most cases the physician can make the diagnosis on the basis of typical symptoms and signs. The typical rapid changes in airway obstruction can be demonstrated by a fall in pulmonary function tests after exercise or inhalation of histamine, and subsequent improvement with an inhaled bronchodilator medication. Many people with asthma have allergies; positive allergy tests support a diagnosis of asthma and may help in identifying avoidable triggers. Other tests (for example chest x-ray) may be required to exclude other lung disease.

Treatment

Symptomatic

Episodes of wheeze and shortness of breath generally respond to inhaled bronchodilators which work by relaxing the
smooth muscle in the walls of the bronchi (airways). More severe episodes may need short courses of oral steroids which suppress inflammation and reduce the swelling of the lining of the airway.

Preventive

Triggers such as pets and
aspirin should be identified and avoided. People with asthma who are having symptoms most days will usually benefit from regular preventive medication. The most effective preventive medication are the inhaled steroids. See also: Asthma medication, Buteyko method\n