Suppurative Pneumonia with Multiple Clustered Abscesses Caused by Staphylococci
In the preliminary report of this commission published in The Journal of the American Medical Association, loc. cit., pg. 111, we described suppurative pneumonia with multiple abscesses caused by staphylococci and cited 4 instances of the lesion which followed influenza. Chickering and Park[[84]] published in a subsequent number of the same journal an account of staphylococcus pneumonia, a lesion which has heretofore attracted very little attention.
In a small group of cases abscesses in the lungs have had characters which serve to distinguish them from the abscesses previously described. Small, sharply circumscribed yellow nodules, which in their centers have undergone suppurative softening, form a cluster upon a red, airless background (Figs. 15 and 16). One or more of these groups several centimeters across, occur in the lungs. It is usually evident that the abscesses are clustered about a medium-sized bronchus, but occasionally with increase in the size of the small cavities the lung tissue assumes a honey-combed appearance.
These clustered abscesses occur in association with bronchopneumonia and have been in all instances associated with purulent bronchitis. The mucosa of the small bronchi may be destroyed so that the surface is eroded. These small clustered abscesses are seen as conspicuous yellow spots immediately below the pleura, but there has been no associated empyema. In 2 instances these abscesses were accompanied by fibrinous pleurisy, but in the remaining autopsies the pleura has been normal. The infrequency of empyema is in contrast with its almost invariable presence when a streptococcus abscess is found below the pleura.
Autopsy 280.—Onset of illness with malaise, headache, cough and fever was on September 24, eight days before death. At autopsy there were hemorrhagic peribronchiolar and lobular bronchopneumonia, clustered foci of suppuration in right lung, purulent bronchitis and fibrinous pleurisy. Hemolytic streptococci were obtained from the consolidated lung and from a bronchus. A culture from the right lung was contaminated. In the bronchus were found B. influenzæ and a few staphylococci. Microscopic examination of the abscesses shows that they contain Gram-staining cocci grouped into staphylococcus-like colonies.
Autopsy 286.—Duration of illness, which began September 25 with symptoms of influenza, was nine days. At autopsy there were lobular and confluent patches of bronchopneumonia, clustered abscesses in the right lung below the pleura, purulent bronchitis, and serofibrinous pleurisy localized in the neighborhood of the abscesses. Pneumococcus IV was obtained from the blood of the heart, and Pneumococcus IV, staphylococci and B. influenzæ from the right main bronchus; growth failed to occur on plates from right and left lungs. Microscopic examination shows the presence of clumps of cocci with staphylococcus grouping in the centers of the small abscesses. Section through one abscess shows its continuity with the wall of a bronchus; along one side of the abscess is epithelium composed of flattened epithelial cells in multiple layers continuous with that of the bronchus; the remainder of the abscess wall is formed by disintegrated lung tissue.
Fig. 15.—Abscesses in two clusters caused by S. aureus in upper part of right upper lobe; confluent lobular consolidation in lower part of lobe. Autopsy 333.
Fig. 16.—Abscesses in cluster caused by S. aureus at apex of right upper lobe. Autopsy 322.
Autopsy 322.—The patient was admitted with influenza eight days before death; signs of pneumonia appeared two days later, and on the following day Pneumococcus IV was obtained from the sputum. At autopsy there were bronchopneumonia with lobar consolidation, abscesses clustered about a bronchus in the right upper lobe and purulent bronchitis. The blood was sterile; S. aureus was obtained from the consolidated part of the left lung; S. aureus and Pneumococcus III from the abscesses of the right lung. Microscopic examination of sections of abscesses showed the presence of Gram-staining cocci in staphylococcus-like colonies, surrounded by necrotic material and polynuclear leucocytes; Gram-negative bacilli resembling B. influenzæ were seen. (See Fig. 16.)
Autopsy 333.—The onset of influenza was fifteen days before death; a diagnosis of pneumonia was made seven days before death. At autopsy there were confluent bronchopneumonia, clustered abscesses in the right lung and purulent bronchitis (no pleurisy). The blood contained Pneumococcus II atypical. S. aureus and Pneumococcus II atypical were obtained from the abscesses; S. hemolyticus, from the consolidated left lung; S. aureus, B. influenzæ and a few hemolytic streptococci, from the bronchus. (See Fig. 15.)
Autopsy 370.—The patient was admitted seventeen days before death and signs of pneumonia were noted three days after admission. At autopsy there were lobular and confluent bronchopneumonia and small abscesses clustered about bronchi and situated within the gray consolidated lung; purulent bronchitis and patches of atelectasis, with distention of the lungs, so that they failed to collapse on removal. No growth was obtained from the heart’s blood; S. aureus in pure culture was obtained from the abscesses of the right lung; S. aureus, Pneumococcus IV and B. influenzæ were obtained from a small bronchus on the left side.
Autopsy 425.—Illness began with influenza twenty-nine days before death; a diagnosis of pneumonia was made fourteen days before death. At autopsy there were chronic bronchopneumonia with tubercle-like nodules of consolidation with some large patches of consolidation, multiple small abscesses giving a honey-combed appearance to part of the right middle lobe, purulent bronchitis and bronchiectasis. S. hemolyticus was grown from the heart’s blood; S. hemolyticus, B. influenzæ and S. albus from the lung. Sections of an abscess contain clumps of cocci. An abscess cavity has along one side remains of a bronchial wall covered by squamous epithelium; a dilated bronchus, cut longitudinally, terminates in this irregular abscess cavity.
Table XLIX shows the incidence of pneumococci, hemolytic streptococci, staphylococci and B. influenzæ in the foregoing autopsies with abscesses clustered about bronchi:
| Table XLIX | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 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 | 4 | 2 | 50.0 | 2 | 50.0 | 4 | 100.0 | 4 | 100. |
| Lung | 6 | 2 | 33.3 | 3 | 50.0 | 4 | 66.7 | 2 | 33.3 |
| Blood | 6 | 2 | 33.3 | 2 | 33.3 | ||||
Staphylococcus shows in the lung the same tendency to produce localized abscesses which it exhibits in other tissues of the body; it invades the lung by way of the bronchi, but shows no ability to invade lymphatics, and in the cases we have examined rarely enters the pleura or the blood. In all of these cases B. influenzæ has been found in the bronchi and perhaps precedes the staphylococcus as an invader of the lower respiratory passages. Pneumococci atypical II, Types III and IV have been found in over half of these cases. The significance of this organism is emphasized by the 2 cases in which it has been found in the heart’s blood at autopsy. It appears not improbable that S. aureus has invaded the lung already the site of bronchopneumonia caused by pneumococci.
Notwithstanding the small number of autopsies, the figures in Table XLIX, showing the incidence of pneumococci, streptococci, staphylococci and B. influenzæ, are cited so that they may be compared with the corresponding figures for the usual type of streptococcus abscess (p. [203]). The incidence of hemolytic streptococci is relatively low, whereas that of staphylococci approximates 100 per cent. S. aureus was present in great number in the lung of Autopsies 322 and 333 and in pure culture in the abscess of Autopsy 370. Microscopic examination of sections from the abscesses which have been described, demonstrated the presence of Gram-staining cocci in characteristic staphylococcus-like clumps within the exudate of the abscesses; scattered chains of streptococci were not found. In those instances (Autopsies 280 and 286) in which cultures failed to demonstrate staphylococci, microscopic examination demonstrated staphylococcus-like clumps of bacteria within the abscess cavity. Cultures were usually made from the consolidated lung near the abscess where the pleural surface could be seared, rather than from the pus, so that in some instances the microorganism has doubtless escaped detection although present.
In association with the multiple abscesses which have been described, injury to the bronchi and bronchopneumonia have been invariably present. Purulent bronchitis has been present in all instances of this lesion; in 2 instances there has been dilatation of the bronchi, and in 1 instance in which the onset of influenza was twenty-nine days before death, there has been advanced bronchiectasis.
Microscopic examination shows that the epithelium of the bronchi is partially or completely destroyed and that destruction of the underlying tissue, with acute suppurative inflammation, penetrates to a greater or less depth into the wall. When the epithelium of the bronchus is wholly destroyed and the lumen is filled and distended with polynuclear leucocytes, a cross section of the tube has the appearance of a small abscess; but more careful examination often shows that the engorged mucosa is still intact. Occasionally, a network of fibrin forms a layer covering the denuded mucosa. Disintegration of the superficial tissue may extend to the muscularis or through it, and may penetrate the wall of the bronchus. The tissue in contact with the exposed surface contains many polynuclear leucocytes and blood vessels plugged with fibrinous thrombi, but deeper in the tissue lymphoid and plasma cells are more numerous. In 2 instances (Autopsies 286 and 425) favorable sections have demonstrated that the wall of an abscess on one side consists of the remains of a bronchus, covered by epithelium composed of squamous cells, Whereas the remainder of the wall, here very irregular, is formed by partially destroyed alveoli plugged with fibrin. The suppurative process has penetrated the wall of the bronchus on one side and extended into the surrounding alveolar tissue. In other instances, abscess cavities occur within the alveolar tissue of the lung and their relationship to bronchi is not evident. In the mass of polynuclear leucocytes which fill the abscess cavity, are clumps of staphylococci in great abundance, usually forming characteristic colonies which are conspicuous with the low power of the microscope.