ENVIRONMENTAL AND BRONCHOALVEOLAR LAVAGE DERMATOPHAGOIDES-PTERONYSSINUS ANTIGEN LEVELS IN ATOPIC ASTHMATICS

Overnight environmental home exposure to Dermatophagoides pteronyssinus in IgE-sensitized individuals is often clinically associated with increased morning symptoms of rhinitis and/or asthma. We have investigated whether household exposure to D. pteronyssinus is associated with the presence of immunoreactive D. pteronyssinus l antigen (Der p l) in bronchoalveolar lavage (BAL) fluid in nine atopic asthmatics sensitized to D. pteronyssinus. Significant environmental concentrations of D. pteronyssinus were noted by light microscopy and immunoassay in the subjects' bedroom carpets(13.4 +/- 3.8 mu g immunoreactive Der p l/g dust), mattresses (27.3 +/- 7.2 mu g immunoreactive Der p l/g dust), and living room carpets (5.9 +/- 1.5 mu g immunoreactive Der p l/g dust). Immunoreactive Der p I was measurable in 20-fold concentrated BAL fluids (3.4 +/- 1.0 ng/ml concentrated BAL fluid) after overnight home exposure. A 24-h hospitalization in a D. pteronyssinus controlled environment (<0.02 mu g Der p l/g dust) resulted in a significant decrease in BAL Der p l concentrations (0.8 +/- 0.6 ng/ml). In vivo studies in nine asthmatics challenged endobronchially with D. pteronyssinus (5-60 ng Der p l) induced significant airway eosinophilia. These studies demonstrate that environmental exposure to microgram amounts of D. pteronyssinus is associated with airway recovery of small nanogram amounts of Der p l.