Comparison of occupational asthma with a latency period and irritant-induced asthma

	Occupational asthma with a latency period	Irritant-induced asthma
Latency period	Present	Absent
Diagnosis	Various – eg, peak expiratory flow monitoring, specific inhalation challenges; IgE-mediated allergy if suspected agent is of a high-molecular-weight nature	History; pulmonary function testing
Pathology	Similar to asthma	Acute: epithelial shedding and hemorrhage
Pathology	Similar to asthma	Chronic: regeneration of epithelial cells; few lymphocytes and neutrophils; increased collagen deposition and thickness of basement membrane
Pulmonary function testing	Better reversibility to bronchodilator	Less reversibility to bronchodilator

IgE: immunoglobulin E.

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