The mediators released by mast cells and basophils can be grouped into two categories:
(1) preformed substances contained within granules and
(2) newly generated chemicals synthesized following cellular activation.
These mediators comprise the effector function of the mast cell. Together they are able to increase vascular permeability, dilate vessels, cause bronchospasm, contract smooth muscle, and summon inflammatory cells. Few cells in the body produce compounds with such a large and varied spectrum of activity. (more…)
By definition, allergy is a condition where a person has hypersensitivity to an environmental, drug, or food antigen (allergen) caused by an altered or unusual immune system reaction to the antigen.
Allergenic foods can impact the lungs when an allergic reaction individual inhales food particles that may have been released when the food was cooked or that were dispersed in aerosol form. Allergy to the allergens in cooked food has been reported by highly allergic patients who were exposed to their allergenic foods (say, fish, shellfish, or eggs) in an enclosed area (for example, a restaurant dining room) or during meal preparation. Most cases of asthma triggered by aerosolized food allergens involve adults engaged in specific occupations that regularly expose them to the allergens. In contrast, most cases of asthma in children are triggered when the allergen is eaten, not inhaled.
Many experts believe that if a baby can be protected from becoming sensitized to the most highly allergenic foods when their healthy immune system and the digestive tract are in the most vulnerable stage for allergy to develop, the incidence of lifelong food allergy and potentially life-threatening anaphylactic reactions to foods will be reduced and hopefully entirely prevented. When a baby has been identified to be at risk for developing allergy, measures to reduce allergic sensitization might be implemented at birth and the problems associated with future food allergy may be significantly reduced. However, as we shall see in later discussions, experts disagree on the best way to avoid this early allergic sensitization.
The reaction of asthmatics to these chemical compounds is not an allergy, but is more correctly described as allergy intolerance because the initial response is not a triggering of the immune system. The process involves an increase in the level of the inflammatory mediators that are responsible for the bronchospasm of asthma. These mediators include histamine and leukotrienes. They are released during the reaction to an allergen, and cause the muscular contractions that result in the difficulty in breathing and wheezing that are typical of asthma. By inhibiting (or turning off) other types of mediators, the chemicals in the food additives cause an increase in the level of antihistamine and leukotrienes. This results in increased bronchospasm, and a definite worsening of the asthma symptoms.
Oral allergy syndrome is an allergic reaction to food that is confined to the oral cavity (i.e., to the lips, and around the lips, roof of the mouth, tongue, hard and soft palate, and uvula) and adjacent structures. It differs from other food allergy in that its symptoms do not appear in any other location in the body, and always accompany respiratory allergy to inhaled allergens of plants, particularly plant pollens. Of course, symptoms in the mouth, throat, and upper respiratory tract can be part of a generalized reaction to foods, but in this case they are more accurately described as oral allergy symptoms. The term oral allergy syndrome applies specifically to pollen allergy (pollinosis) accompanied by reactions to certain raw foods when they are in direct contact with oral tissues. Individuals with Oral allergy syndrome typically have hay fever symptoms caused by allergies to trees, grasses, and weeds. They experience irritation in the mouth (lips, tongue, roof of the mouth) and sometimes the throat after eating specific types of raw fruits, vegetables, and sometimes nuts.
There are other signs and symptoms of asthma. People with asthma can be feeling irritable because of asthma discomfort. Some signs usually occur before an asthma attack. Asthma is a chronic disease of the lung, which affects respiratory system. Respiratory system is like small tubes that take the air in and out of the lungs. (more…)
Exercise-induced asthma is a feeling of shortness of breath, with the presence of cough, wheezing, and chest tightness after physical exercise.
Normally the bronchial tree and bronchial vessels responds to exercise with increasing radius of the interior of the bronchi (bronchodilation), (more…)
How to properly make clinical diagnosis of acute severe asthma? There is little doubt of the accuracy of current asthma testing. This is because most patients had bring out an established asthma diagnosis from prior regular asthma treatment, before presenting it to Asthma Emergency Department. We can see that most of patients had physical presentation: sitting up right, had profusely diaphoretic, only manage to speak only a few words at a time, and obvious respiratory distress. We can see varying respiratory rate on most patients. Hyperventilating is common in proportion to the severity of asthma attack. On the other hand, patients with hypoventilation is an indication of impending respiratory arrest. (more…)
