At high magnification, the numerous eosinophils are prominent from their bright red cytoplasmic granules in this case of bronchial asthma. There are two major clinical forms of asthma that can overlap.
Extrinsic asthma: there is typically an association with atopy (allergies) mediated by type 1 hypersensitivity, and asthmatic attacks are precipitated by contact with inhaled allergens. This form occurs most often in childhood.
Intrinsic asthma: asthmatic attacks are precipitated by respiratory infections, exposure to cold, exercise, stress, inhaled irritants, and drugs such as aspirin. Adults are most often affected.