| Staphylococci | 1 |
| B. influenzæ, pneumococci | 1 |
| B. influenzæ, S. hemolyticus | 2 |
| B. influenzæ, pneumococci, staphylococci | 1 |
| B. influenzæ, S. hemolyticus, staphylococci | 4 |
| No organism found | 1 |
The high incidence of B. influenzæ and the frequent association of B. influenzæ and hemolytic streptococci are noteworthy. The instance in which no organisms were found is probably due to a defect in media and should perhaps be excluded from the list.
The percentage incidence of pneumococci, hemolytic streptococci, staphylococci and B. influenzæ in the bronchus, lungs and blood of the heart is an index of the facility with which these microorganisms penetrate internal organs when the bronchi are the site of this hemorrhagic lesion.
| Table XLI | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| NO. OF CULTURES | PNEUMOCOCCI | HEMOLYTIC STREPTOCOCCI | STAPHYLOCOCCI | B. INFLUENZÆ | |||||
| NO. POSITIVE | PER CENT POSITIVE | NO. POSITIVE | PER CENT POSITIVE | NO. POSITIVE | PER CENT POSITIVE | NO. POSITIVE | PER CENT POSITIVE | ||
| Bronchus | 10 | 2 | 20.0 | 6 | 60.0 | 6 | 60.0 | 8 | 80.0 |
| Lung | 13 | 4 | 30.8 | 7 | 53.8 | 3 | 23.1 | 5 | 38.5 |
| Blood | 17 | 4 | 23.5 | 9 | 52.9 | ||||
When these figures are compared with those for all forms of bronchitis no very noteworthy differences are found; the incidence of pneumococci here is less and that of hemolytic streptococci greater. In association with the severe changes present in the bronchi, hemolytic streptococci which enter the lungs almost invariably find their way into the blood.
In 6 instances there has been frank pneumonic consolidation limited to a zone encircling small and medium-sized bronchi which have often been obviously dilated. On cross section these patches of pneumonia are circular, from 1 to 2 cm. in diameter and each contains a bronchus at its center. When the bronchus is cut longitudinally it is evident that pneumonic consolidation forms a cylindrical sheath about the tube. The consolidation varies in color from red to grayish red. In one instance (Autopsy 253) the consolidated tissue has formed a gray zone in contact with the bronchus and is red in a peripheral zone; microscopic examination shows that the alveoli about the bronchus contain fibrin, whereas those at a greater distance contain red blood corpuscles. In this instance, the associated pneumonia in another part of the lung has been somewhat anomalous and has had characters both of lobar and bronchopneumonia, for scattered in the left lung there have been patches of firm consolidation not more than 2 cm. across. The smaller of these patches are deep red, but the larger are coarsely granular and gray in the center. The patchy character of the lesion has suggested bronchopneumonia, but the coarse granulation on section and the presence of fibrinous plugs within the small bronchi have presented a close resemblance to lobar pneumonia. This autopsy is one of the few instances in which Pneumococcus II has been found, Pneumococcus II being present in blood and lungs, B. influenzæ, in lungs and bronchi. In 2 additional instances (Autopsies 374 and 392) peribronchial pneumonia, recognizable at autopsy, has been associated with consolidation having the characters of lobar pneumonia. In one instance, Autopsy 374, the right lung has contained two patches of firm, mottled red and pinkish red coarsely granular consolidation each about 6 cm. across, one situated in the upper lobe and the other in the lower lobe. Elsewhere in the lung, in definite relation to dilated bronchi, occur patches of firm, red, coarsely granular consolidation from 1 to 1.5 cm. in diameter when cut transversely. The bronchus in the center has contained purulent fluid. In the opposite lung similar consolidation has been limited to zones about dilated bronchi which contain purulent fluid. Pneumococcus IV has been obtained from the blood of the heart.
The peribronchial pneumonia which has been described occurs in association with evidence of profound injury to the bronchial wall. In 5 of 6 instances purulent bronchitis has been found at autopsy; in half of these instances bronchiectasis has been noted. The epithelium of the bronchus has been found separated from the underlying tissue by serous exudate, blood and leucocytes; epithelial cells undergo necrosis and disappear, the denuded surface being covered by fibrin. Necrosis extends a varying depth into the wall of the bronchus; blood vessels are engorged, and there is in some instances hemorrhage throughout the wall of the bronchus.
The character of the exudate in the alveoli surrounding the bronchus differs considerably in different instances. In some instances (Autopsies 374 and 392) red blood corpuscles are predominant in the alveoli in contact with the bronchial wall, whereas in a peripheral zone polynuclear leucocytes are more abundant. In other instances (Autopsies 253 and 402) alveoli next the bronchial wall contain abundant fibrin and these are surrounded by a zone in which the alveoli are filled with blood.
Peribronchial pneumonia is the result of the direct extension of the inflammatory process through the wall of the bronchus; it occurs when the epithelium of the bronchus is destroyed and the underlying tissues are injured, but may be present in a wide encircling zone even when the lesion has not penetrated the bronchial wall. The distribution of the pneumonia demonstrates very clearly that the inflammatory process does not reach the affected peribronchial alveoli by way of the bronchioles tributary to the bronchus.
The bacteriology of these instances of peribronchial pneumonia is noteworthy. (Table XLII.)