Association of increased number of bronchoalveolar lymphocytes with patient age and IgE-mediated allergic reaction

The proportion and number of lymphocytes in the airways were analyzed in 15 patients with a high proportion of lymphocytes in bronchoalveolar lavage (BAL) fluid (more than 30%) and in 17 patients with less than 20% of BAL lymphocytes. 1. Both atopic and nonatopic asthma patients with a high proportion of BAL lymphocytes were aged more than 50 years. In contrast, the age of patients with less than 20% of BAL lymphocytes ranged widely, from 29 to 63 years, in the two asthma types. 2. Age at onset of the disease, serum IgE levels, and ventilatory function test were not related to the proportion of BAL lymphocytes. 3. In patients with a high proportion of BAL lymphocytes, the mean proportion of these cells was 47.3% in atopic patients and 36.4% in non-atopic patients, i. e., there was no significant difference between the two asthma types. The absolute number of BAL lymphocytes in these patients was significantly higher in atopic (5.62×10(6)) than in nonatopic asthma (0.77×10(6)) (p<0.01). These findings show that an increased number of lymphocytes in the airways is clearly related to patient age and IgE-mediated allergic reaction.