A young runner with history of seasonal running nose, complains of sudden onset dyspnea early morning that improved after 2-3 hours. He has history of similar episodes in the past.on examination, patient is tachypneic, diffuse polyphonic expiatory wheeze heard on auscultation of chest, His x-ray is  normal. All except one is true regarding the clinical scenario.
Clinical features are suggestive of Bronchial Asthma. There is no necrosis of airway in Bronchial Asthma.
Diffusion Lung capacity for carbon monoxide is Normal
FEV1% is decreased
Necrosis of airways
Microvascular leakage resulting in airway edema.and plasma exudation into airway lumen