[The etiologies of asthma]

Asthma may have several etiologies. It is well-known that there are allergic subjects with low IgE bound to mast cells, with negative specific RAST and with weakly positive skin tests, but with a positive provocation test with pneumo-allergens. Food allergy, isolated or associated is also not a negligible cause. Non-allergic subjects often respond to triggering factors: Gastro-oesophageal reflux Neuro-endocrine origin Infectious origin Physical origin (exercise). In our study, we place the emphasis on two types of extremely severe asthma, linked to intolerance of aspirin and metabisulphites and often associated.