Asthma classification by pathophysiology and IgE-mediated allergic reaction: new concepts for classification of asthma.

Bronchial asthma was classified by the pathophysiology and by the mechanism of onset of the disease. Forty asthmatics who had serum IgE levels lower than 200 IU/ml were evaluated by two classification methods. 1. In asthma classified by a score based on clinical findings and examinations, the characteristics of the findings and examination results were compared among three asthma types, i.e., Ia. simple broncho-constriction type, Ib. bronchoconstriction+hypersecretion type, and II. bronchiolar obstruction type. Type Ib patients, in addition to manifesting hypersecretion, had a significantly higher proportion of eosinophils in the bronchoalveolar lavage (BAL) fluid compared to other asthma types. Significantly decreased values for ventilatory parameters and an increased proportion of BAL neutrophils were found in type II compared with other asthma types. 2. In a new classification by mechanism of onset, asthma was classified into three types according to the degree of participation of IgE-mediated reactions associated with specific IgE antibodies and serum levels of total IgE: asthma induced by definite IgE-mediated reaction (atopic asthma), possible IgE-mediated reactions (asthma), and asthma induced by non-IgE-mediated reaction (asthma syndrome).