[The changes in plasma histamine levels after a sulpyrin inhalation test in asthmatic patients].

A sulpyrin inhalation test was given to 13 patients with aspirin-induced asthma (AIA) and 8 patients with non-aspirin-induced asthma (non-AIA) to observe the changes in plasma histamine levels before and after challenges. The respiratory function (FEV1.0) was measured before and after sulpyrin inhalation. A decrease of more than 20% the initial value (basal value) was defined as a positive response. Plasma histamine was determined by high-performance liquid chromatography (HPLC). In 11 patients with AIA, a positive response was observed (SIT positive), with a fall of FEV1.0 to 63.70 +/- 4.87% of the basal value. In 2 patients with AIA and 8 patients with non-AIA, no positive response was observed (SIT negative). In patients with SIT positive, plasma histamine levels increased significantly from 0.61 +/- 0.06 ng/ml before challenges to 1.34 +/- 0.22 ng/ml after challenges (p less than 0.01). No significant changes of plasma histamine occurred in the SIT negative patients. These results suggest that mast cells play some role in the mechanism of the development of aspirin-induced asthma.