Non-specific bronchial hyperreactivity (NBHR) and late-asthmatic reaction events after allergen- challenge

The aim of the study was to correlate the NBHR with the occurrence of late allergic bronchoconstriction (LAB), change of peripheral blood eosinophil count (Eo), percent of CD25 positive CD4 T lymphocyte and total leukocyte count. The 42 allergic patients (pts) with rhinitis (R = 10) and asthma (A = 32), (mean age 25, range 15 - 37 yrs.) with mean global IgE 570 kU/L and mean specific IgE (18.25 PRU) were investigated. Bronchial challenge test was done by dosimeter method (output of nebulizer 5.8 mL/breath). Phenotypic analyses of lymphocytes were performed by flow cytometry (mAB Becton Dickinson). Distribution of NBHR severity was as follows: asthmatic range of NBHR (PD2oFEV1 met 1.8 mmola): 10 pts (5 A, 5 R). The severity of NBHR correlates statistically significant with: the occurrence of LAB, basal FEV1 (r = 0.38, p = 0.009), intensity of EAB (p = 0.00), fall in Eo 2 hours after bronchial challenge (p = 0.05), increase of Eo 48 hours after challenge (p = 0.02), the increase of CD4CD25 percent (p = 0.004) and increase in total leukocyte count in peripheral blood. LAB occurred in 17 pts (40%) with mean fall in FEV1 309%. Distribution od LAB according to severity of NBHR was: 11 pts in asthmatic range and 6 pts with mild severity of NBHR. None with normal NBHR developed LAB. The intensity of EAB did not correlate with changes of inflammatory cells. These data suggest that NBHR severity is a good marker of late allergic bronchial cascade in sensitized patients.