Asthma is a very common chronic disease. It is estimated that between 10-18% of the population in the developed world suffers from asthma. Asthma is secondary to hyperresponsiveness of the airways. In people with asthma, the airways react to various triggers with spasm of the muscle that surrounds them, which reduces its diameter, and with an inflammatory process which produces multiple secretions, further reducing its internal diameter.
The resulting narrow diameter of the airways particularly compromise the expiration and, as a result of this, the lungs become hyperinflated with oxygen-poor air. The respiratory secretions further disrupt the lung function and can block the small airways.
Asthma exacerbation present with shortness of breath, cough, wheezing, respiratory secretions, feeling of chest tightness and itching around the airways. It is important to note that between exacerbations, a person with asthma can be completely free of symptoms and even his physical examination may be normal. The reason why some people develop asthma is not clear. People with asthma may flare up after exposure to some allergic triggers (if they have developed hypersensitivity to them) such as house dust mites, molds, animals, cockroaches, trees pollen, grasses pollen, weeds pollen. It is important to note that people with asthma may flare up or worse their condition after exposure to some irritants such as "bleach" (chloride), certain cleaning substances, certain scents like perfumes and more. Other diseases can also cause asthma flares, prominent among them viral diseases of the respiratory tract. Sometimes occupational factors may cause asthma, for example, a chef's prolonged exposure to flour, a carpenter's prolonged exposure to some trees' wood and more. Some people who suffer from asthma have exacerbations after exposure to cold air or after physical effort.
Asthma has a wide range of severity; there are very severe cases of asthma, even life-threatening (every year a quarter of a million people die around the world from asthma). At the same time there are many cases of people who suffer from asthma and can live their entire lives without being diagnosed and without treatment, but in many of these cases the mild exacerbations that these people have hurt their quality of life and most of them will live without knowing that they could live feeling better. These people suffer under certain conditions from uncomfortable breathing, persistent cough after viral diseases, physical effort intolerance due to cough, and most of them are used to live this way. Not every case of asthma has wheezing, not every case of asthma is easy to diagnose.
The diagnosis of asthma is dependent firstly on clinical suspicion. Asthma not always shows typical manifestations. For diagnosis the physician performs a spirometry test or pulmonary function tests. These tests are designed to demonstrate reversible airway obstruction as the typical signature pattern of asthma. Sometimes, when there is a very high suspicion of asthma and the above tests fail to demonstrate a pattern compatible with asthma, a metacholin challenge may be ordered. Metacholin challenge is performed in a hospital setting. During the test the patient breathes an inhalation containing methacolin. In people having asthma the airways respond to methacolin with spasm at low methacolin concentrations as opposed as in people without asthma. It is important that people with asthma undergo allergy testing to rule out environmental triggers, among them house dust mites, molds, animals, cockroaches, trees pollen, grasses pollen, weeds pollen.
It is central in asthma treatment that the exposure to environmental triggers is avoided if possible. People with mild asthma may need sometimes a bronchodilator inhaler like Ventolin or Aerovent. Those asthmatic patients that flare after exercise can prevent this by using a bronchodilator inhaler half an hour before physical effort.
People with asthma severity beyond that should also receive a corticosteroid inhaler to prevent flares. Inhalers combining bronchodilators and corticosteroids (like Symbicort and Seretide) are the next step in therapy. Those who cannot be successfully kept in remission with this treatment, can receive additional drugs such as Singulair or oral corticosteroid tablets. In severe cases, the addition of Xolair - an antibody directed against IgE (the antibody of allergy) may be helpful.
Rarely and only in cases where there is evidence of a major role of an environmental trigger against which there is an available vaccine, immunotherapy (allergy vaccines) can be added to the treatment. It is important to note that for this treatment it is necessary to visit the doctor weekly for a period ranging from 3-5 months, and then monthly for another 3-5 years. Side effects may occur during vaccine treatment, such as swelling at the injection site (the arm), itching, and even widespread symptoms like itchy rashes and rarely shortness of breath like in asthma exacerbations. Vaccine treatment, which is needed for some patients, implies heavy logistics for the patient and there is a risk of adverse responses. The risk of asthma flare-up after the vaccine should be a major consideration of benefit against risk for this treatment.
In conclusion, asthma is a disease much more common than people think and many people with chronic cough or difficulty breathing after viral diseases suffer from asthma, which affects their quality of live. Asthma treatment is usually very successful.