Post-mortem examination showed little of interest aside from the thorax. The left pleural cavity contained 75 cubic centimeters of slightly cloudy fluid. The right was almost completely obliterated by an organizing fibrinopurulent exudate which bound together the visceral and parietal layers. The left lung was partially collapsed and covered by a thickened pleura, bluish purple in color, which at the base and in the interlobar area was finely granular. Crepitation was present at the apex, the anterior surface, and the borders of the lung; elsewhere the consistency was increased. On section there was a frothy exudate from the apex and extreme base. These were deep red in color, while the intervening surface of the lung was paler, but broken by many small, white, elevated nodules which at first glance resembled tubercles (Fig. [XXXIX]). On close examination each of these was seen to have a small, depressed center from which pus could be expressed, and on dissection this was seen to be the wall of a bronchiole. The right lung was more voluminous and covered by a thick, grey, fibrinopurulent exudate except on the upper anterior border where there were a few small areas of interstitial emphysema. On section the pleural exudate was seen to be sharply demarcated from the lung parenchyma by a fine red line. The pseudotubercles of the other lung were here even more marked and from each exuded a yellow pus which partially obscured the pinkish-grey translucence of the surface (Fig. [XL]). The lumina of the larger bronchi were distended. The hilic and bronchial glands were enlarged and grey.
Microscopic examination of sections from the lung showed an extensive bronchopneumonia. The alveoli of an occasional group of lobules were filled with serum or red blood cells, while still other areas showed foci of necrotizing pneumonia, actual miliary abscesses in which there were large clumps of bacteria (Fig. [XLI]). Throughout the sections, however, the striking change was an organization of the exudate, which varied from a few fibroblasts to a well defined connective tissue almost obliterating the normal architecture (Figs. [XLI] and [XLIV]). The alveolar walls in some areas showed edema only, in others they were almost replaced by a thin line of fibrous tissue, and in still others, by a hyperplasia of the epithelium which almost filled their lumina. The bronchi exhibited similar changes, their lumina were filled with an exudate of desquamated epithelium and leucocytes, which in some places was organizing (Fig. [XI]), and there was a regeneration of epithelium evidenced by a piling up of the cells and the presence of mitotic figures in them. The interstitial tissue showed some edema. The tracheal epithelium was intact, but a few leucocytes and lymphocytes were scattered through the submucosa.
Pneumococcus Type II was recovered from the blood, pleural fluid, and lung. B. influenzæ was also demonstrated in the lung by smears and cultures.
In contrast to this example of a very diffuse, organizing pneumonia, associated with a marked peribronchial organization where the illness lasted for three weeks with hardly a remission throughout its course, the following example of necrotizing and organizing lobar pneumonia may be considered.
Autopsy No. 183.
A white male, aged 46 years, was admitted to the New Haven Hospital on January 9, 1919, complaining of “pneumonia.” The family history was unimportant. He stated that he was in the hospital twelve years ago with typhoid fever and again five years ago with acute cholecystitis.
His present illness began two weeks previous to admission with chills, fever, anorexia, nausea, vomiting, and a slightly productive cough. He was prostrated and drowsy, but could not sleep. On admission his temperature was 101.5°F., the pulse 124, and the respirations 34 per minute. He was cyanotic and dyspnœic. The right chest showed signs of consolidation, and fluid below the 3rd interspace. The white blood count was 8,200 cells per cubic millimeter, 89% being polymorphonuclear leucocytes. The patient died eighteen hours after admission.
The autopsy was held four hours after death and the essential findings were as follows:—
Twelve hundred cubic centimeters of fibrinopurulent fluid were found in the right pleural cavity and the visceral and parietal pleura had a thick, yellow coat of fibrin. The right lung was voluminous, retained its shape on removal, and weighed 1,800 grams. The lower two lobes were consolidated and the upper lobe was atelectatic. On section the latter was slightly congested, but not consolidated. The lower two lobes were fairly smooth and grey, mixed with red areas, and exuded thick, sanguinous pus. They also showed several necrotic areas in the central portion and, in some instances, cavities 1 centimeter in diameter filled with sanguinous pus had formed. The bronchi contained the same material, and on its removal a deep red mucosa was exposed. The left lung showed some fibrous pleurisy over its lateral, posterior, and diaphragmatic surfaces. There was a firm, puckered scar at the apex. The lung crepitated throughout, and on section was essentially normal except for moderately intense injection of the bronchi. The hilic nodes were enlarged, soft, succulent, moderately injected, and pigmented. The trachea was pale, but was covered by a mucopurulent exudate. The right side of the heart was moderately dilated. The spleen was not enlarged, but was softened and congested. The liver was pale, slightly decreased in consistency, and congested. The kidneys and adrenals showed cloudy swelling. The gall-bladder contained several stones, had a thickened wall, and was bound to the pylorus by firm, fibrous adhesions.
Microscopic examination of the lung showed the alveoli filled with an acute inflammatory exudate in many stages of degeneration and hyalinization (Fig. [XLII]). Abscesses were frequent, but were for the most part small. A similar necrotic mass was contained in the bronchi. There were, however, features of the microscopic picture that outweighed those already described. The alveolar and bronchiolar exudates were everywhere being invaded by a young granulation tissue, rich in fibroblasts and capillaries. Mononuclear cells abounded in the new tissue. Even more striking than the mesodermal new growth was the epithelial proliferation which could be seen in many areas. It not only attempted to cover the denuded bronchial surfaces, but stretched over masses of exudate and granulation in the lumina and extended in tongue-like projections for a considerable distance into the surrounding lung tissue (Fig. [XLVIII]).