I should clarify for the more specific aspects of the discussion that you can have EIA without other asthma manifestations (although it is correctly stated as being the definite exception). EIA is still a form of asthma, just a specific uncommon manifestation. You can't to my knowledge have current EIA without bronchial reactivity, therfore negative methacholine excludes asthma and therefore also excludes EIA. The above description by Sessamoid is correct to my understanding.

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