Am. J. Respir. Crit. Care Med., Vol 151, No. 1, 01 1995, 71-74.
Environmental and bronchoalveolar lavage Dermatophagoides pteronyssinus antigen levels in atopic asthmatics
P Ferguson and DH Broide
Department of Medicine, University of California, San Diego 92103.
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 I antigen (Der p I) 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 micrograms immunoreactive Der p I/g dust), mattresses
(27.3 +/- 7.2 micrograms immunoreactive Der p I/g dust), and living room
carpets (5.9 +/- 1.5 micrograms immunoreactive Der p I/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 micrograms Der p I/g dust) resulted in a significant decrease in BAL
Der p I concentrations (0.8 +/- 0.6 ng/ml). In vivo studies in nine
asthmatics challenged endobronchially with D. pteronyssinus (5-60 ng Der p
I) 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 I.
