Type II (bronchiolar obstruction) asthma and number of neutrophils in bronchoalveolar lavage (BAL) fluid

Bronchial asthma is classified into three types ; type Ia (Ia-1 and Ia-2), type Ib, and type Ⅱ, by clinical symptoms (clinical diagnosis). Asthma is also classified by clinical findings and examinations (score diagnosis). Both classification systems show that markedly increased proportion of BAL neutrophils and marked decrease in % V25 value are characteristic of type Ⅱ, bronchiolar　obstruction, asthma. However, there are some type Ⅱ asthma patients without BAL neutrophilia. In these patients, age is higher compared to those with BAL enutrophlia. Decrease in FEV1.0% value and decrease in the proportion of BAL lympocytes and serum IgG level, are not so remarkable as decrease in those with BAL neutrophilia. It has been suggested that type Ⅱ asthma with BAL neutrophilia correlates with suppression of humoral and cellular immunity, and same type of astma without BAL neutrophilia is in part caused by aging.