[Platelet aggregation in asthma]

Platelet activation is one of the aspects of cellular interaction causing inflammation in asthma. Platelet aggregation has been studied in asthmatic patients in presence of different aggregation inducers (epinephrine, ADP, arachidonic acid). In 20 to 40% of the atopic asthmatic patients depending on the inducer and in some patients with non atopic asthma or aspirin sensitivity and asthma platelet aggregation is decreased. Bronchial provocation tests have not decreased platelet aggregation except in few cases. In vitro incubation of platelets with allergen extract has provoked an hypoaggregation mainly when incubation time or allergen concentration were increased. Platelets seem to play an important role in the inflammatory component of bronchial asthma.