Analysis Of Allergen And Detection Method In Children With Asthma

Bronchial asthma is a global disease. There are about 200,000,000 people suffered with asthma in the world. In China, the morbidity of asthma among children was between 0.5%~2%, while in some regions it is about 5%. However, with the development of industries, the morbidity has met an increase rise over the world, especially among children. Asthma has drawn the attention of the whole world as a serious hygienic problem.Asthma is a chronic disease characterized by an increased responsiveness of the airway caused by eosinophil, mast cell, T-lymphocyte and various cytokines. Some factors can induce the exacerbations of asthma, such as inhalational allergens, food allergens, drugs, change of weather, passions, sports and pregnancy and so on. In most cases, exacerbations of asthma is directly correlated to typeⅠallergy after exposed to allergen. The allergen would make the B lymphocyte of the body to produce specific IgE and banded to the receptor after it enters the body that is allergic constitution, by means of delivering by macrophage and T-lymphocyte. If the allergen makes a second invasion, it could bind to the IgE in the surface of mast cell and eosinaphil, and therefore cause a series of reactions within cells and urge the cell to produce and release various active medium, which would cause smooth muscle contraction, inflammatory cell infiltration and so forth. With the effect of medium, inflammatory would secret a couple of sorts of medium and enhance the airway lesion, increase the inflammatory infiltration and at last, brings out the clinical symptoms of asthma.In 2006, GINA (Global Initiative for asthma) proposed 5 agenda to manage and prevent asthma, one of which was to definite and reduce the exposure of potential dangerous factors. Though with the allopath of medicine against diagnosed cases, the symptom and the conditions of life are promoted, we should still try to avoid direct exposure to dangerous factors to prevent attack and symptom of asthma. Further more, we should cut off the contact to certain dangerous factors of the patients to control asthma and reduce the use of medicine.Through the test of specific IgE, we can definite the allergen and avoid the exposure, which is of high importance to asthma.This research would make a study on the disperse in allergen and the difference of ages and genders and make a comparison of the rate of sensitivity and specificity of various allergen-test method。Method of experiment: By means of Allergy-Screen, tested the allergens among 122 children with asthma (male 83, female 39, infants 72 and children 80), and 30 cases to take the skin prick test.Results: 87 among 122 were positive in the test of 14 allergens, the percentage was 59.83%. In the above there were 26 infants and 47 children and there was no obvious difference between the two age groups. As to the 14 allergens the affirmation in mites was the highest: 21.31%. Close after that would be cat fur, dog fur and grass: 16.39%. Mould, beef and lamb, and milk also took a good part of it: 10.66%, 9.02%and 6.56%. Among the inhale groups, infants and children had little difference (P>0.05). Among the food allergen groups, infants would be higher in the rate of allergen would be higher (P<0.01). The positive rate of allergen of infants had no difference between inhalational and food allergens groups, while in children, the positive rate of inhalational allergens group would be higher. In children's group, more than 3 kinds of allergens were higher in positive rate than infants.The test of the total IgE showed that the most children(75.8%) with asthma who have certain allergen have the higher level of IgE, while there is also have little part (38.5%)of children without any allergen whose level of IgE is high. The total IgE is closely related to the result of allergen.This experiment showed that within Changchun Region, the most important allergen be mite among all the allergens, and cat fur, dog fur, grass, mould, beef and lamb and milk may be also important allergens. Among the above, mite be yet the biggest threat in this region.As to the phenomenon that allergens of infants had no difference between inhale and food groups, while in children, the positive rate of inhalational allergen would be higher than food allergen. In children's group, more than 3 kinds of allergens are higher in positive rate than infants, we can see that with the growth of age the allergens of children to food was decreasing while the sensitivity to inhaling is increasing. As to the difference in structure of allergen among different age groups, the reason of allergy of food is the immature of gastrointestinal and the immune systems and the secretion is yet needed to develop, the food digested is also a kind of allergen.The morbidity of asthma of males would be higher than females'. The positive rate had no difference in genders and this suggests that the high rate of morbidity of male of asthma may be not related to allergen.The test of the total IgE showed that the most children with asthma who have certain allergen have the higher level of IgE, while there is also have little part of children without any allergen whose level of IgE is high. The total IgE is closely related to the result of allergen. Above all, we can have the conclusion: the total IgE cann't diagnosis and exclude the allergy, the higher level means the higher allergic possibility.This study made a test in two methods to 30 cases of children with asthma, the sensitivity and specificity of mite, dog fur, cat fur and grass was high. The two methods were reliable and liable.