Irritant-induced asthma

Bronchial biopsy taken three days after acute accidental inhalation of high concentration of chlorine showing almost complete desquamation of bronchial mucosa (upper part) with fibrinohemorrhagic deposits (dark pink) and inflammatory influx of neutrophils (dark purple spots in the middle and upper portions). Normal smooth muscle is shown in the lower portion. Weigert-Masson stain.

Low-power photomicrograph of normal lung tissue shows open alveoli with thin, capillary-containing interstitial spaces. An artery (A) is identifiable by its thick, muscular wall; the accompanying bronchus (B) contains mucoid material and is lined by columnar respiratory epithelial cells.