Further history: This 69-year-old man, who died on 2/9/96, had suffered from asthma since 1988. He had been hospitalized once for asthma in 1989. For the last 2 years he was treated with bronchodilators, intermittent antibiotics, and steroids. Exacerbations appeared to be related to respiratory tract infections. He visited the clinic on 1/10 for 2 wks of cough, sputum, fever to 100° F, and mild dyspnea. At that time he had an oxygen saturation on room air of 96% and mild expiratory wheezes. Septra, solumedrol, and bronchodilators were continued. On 1/31 he had increasing dyspnea, wheeze, and sputum, but he was able to continue working until 2/8 when he developed severe dyspnea. After using bronchodilators, he went to bed, but awoke at 4 am with difficulty breathing and had a respiratory arrest.
Radiographs from this patient are not available, but a chest radiograph from another asthmatic person illustrates some features of asthma.
Histologic features: A longitudinal section through a bronchus is shown below. Name five features of asthma that can be seen. Answer.
Histologic changes: The section (A) shows a lumen filled with mucus and sloughed epithelial cells. The sloughed cells are partly a result of the disease and partly a postmortem change. Nodules of hypertrophied smooth muscle (arrow) give a corrugated contraction of the lumen. The vascular hyperemia is related in part to inflammation and in part to agonal effects. The collections of blue inflammatory cells are mostly lymphocytes and plasma cells.
At higher magnification (B), the epithelium is mostly intact but infiltrated by inflammatory cells. The thick, pink line below the epithelium represents collagenization by types 3 and 5 collagen under the basement membrane. The thickening is a result of chronic inflammation. It is not a thickening of the basement membrane itself. The subepithelial tissue is thickened by an intense inflammatory infiltrate, smooth muscle hyperplasia, and mucous gland hyperplasia. Cartilage lies at the lower right.
Clinical summary Image 3
Table of Contents
1) Luminal mucous plug, 2) sloughed epithelium, 3) smooth muscle hyperplasia, 4) mucosal inflammation, 5) mucosal hyperemia.