Part 10

Here, as in the discussion of the involvement of the lymphadenoid tissue, the most outspoken changes are in the thorax. Frequently thrombi are encountered in the vessels of the lung (34, 138). This does not include the capillary thrombi associated with damage to the alveolar walls already discussed. It has not been possible to demonstrate an association between the hemorrhagic, infarct-like foci in the lung and these vascular complications (47). The thrombi, histologically, are most frequently propagated, but occasionally an indication of their etiology is found in a destructive lesion of the vessel wall (19, 47, 50, 108, 156). This arteritis or phlebitis may be embedded either in a pneumonic zone or in relatively normal lung. The vessel wall may be obscured by a cellular infiltrate throughout its circumference or only at one point. The cells, on account of karyorrhexis often difficult to identify, are, partly at least, polymorphonuclear leucocytes, and the thrombus which forms upon the inflammatory nucleus, as a rule, is fairly rich in these cells (Fig. LII).

This vascular lesion may involve either artery or vein and may be found either within the lung or at distant points. Not infrequently, pulmonary embolus terminates influenza. One instance of this is incorporated in the group of chronic influenzal cases detailed above (Fig. LIII). In this instance, the thrombus originated in the right iliac veins; and, although no attempt was made to demonstrate the primary vascular lesion, so many similar cases are recorded (7, 82), and vascular damage is so frequent in this disease, that the hypothesis attributing pulmonary embolus to a thrombus initiated by a phlebitis is strongly supported.

Parenchymatous and skeletal lesions of hemorrhagic type, although variable quantitatively, are frequent and involve the muscles, the parenchymatous organs,—the adrenal especially,—and the mucosa of the alimentary canal. They have been described already with regard to the pleural surface and they may occur in other serous membranes.

FIG. XXXII. AUTOPSY NO. 100. A HIGHER MAGNIFICATION OF THE LESION ILLUSTRATED IN FIGURE XXXI. THE ALVEOLAR WALL IS ENTIRELY NECROTIC: BACTERIA AND POLYMORPHONUCLEAR LEUCOCYTES ARE ABUNDANT. ]

FIG. XXXIV. AUTOPSY NO. 87. CROSS SECTION THROUGH THE AREA OF GANGRENE SHOWN IN FIGURE XXXIII. ]

FIG. XXXV. AUTOPSY NO. 160. MICROSCOPIC DRAWING OF THE GANGRENOUS CAVITY ILLUSTRATED IN FIGURES XXXIII AND XXXIV. ]

Only two examples of hemorrhage in the recti muscles were encountered in the ninety-five autopsies. In other localities this lesion has not only been more frequent but also more extensive (2, 47, 50, 128, 140, etc.). However, it has been fortunate that the two instances in this series represent a fresh hemorrhage and the healing lesion, respectively. The fresh hemorrhage is quite characteristic of Zenker’s necrosis involving muscles. Grossly, it is a small lesion and does not involve the entire width of the rectus muscle, as may happen, with a resulting rupture of this structure (12, 162). Microscopically, many of the muscle cells have lost their striation, are irregularly swollen, and, as fractures in them indicate, are apparently brittle. Between the muscle fibers and where these are lacking, the predominating element of exudate is the red blood cell, but there is a considerable amount of fibrin and also some serum between these cells (Fig. LVI). The absence of polymorphonuclear leucocytes is noteworthy. The second example of a muscular lesion occurred in a patient who died on the twenty-fifth day of the disease. Grossly, this also was a small lesion, although the muscle fibers at its site were obviously ruptured. Histologically, the lesion is a healing one. Regeneration of the muscle fibers (47, 156), as illustrated by the formation of typical spindles, is handicapped by the rapid development of the fibrous scar (Fig. LVII). Suppuration had not occurred and this also has been true for the focal, hemorrhagic, inflammatory processes which were encountered in many different localities throughout the body.

Perhaps the focal hemorrhagic lesions were most frequent in the adrenal gland. Generally, they were located in the cortex, although medullary hemorrhages were encountered. The extent of the process varied from minute hemorrhages, associated with necrosis of only a few cells, to extensive ones involving half of the adrenal. The microscopic examination of the exudate revealed the same elements and in approximately the same proportions as described for the similar process in the muscles. Not infrequently, mitotic figures in the adrenal cells indicated an attempt at repair of a minute damage.

Hemorrhages in the mucosa of the alimentary canal, including the stomach and intestines, similar to those so common at the post-mortem table in many different types of acute infectious disease, are, of course, common in influenza; but, in one case especially, a lesion was encountered which adds significance to these hemorrhages (47). Here areas of mucosa, usually round or oval and varying from one-half to two centimeters in diameter, often with ulceration in their centers, show, microscopically, bacterial emboli in the vessels of the mucosa with a hemorrhagic effusion which obliterates the architecture of this coat and extends at some points into the submucosal and muscular layers (Fig. LVI). Here, the occurrence of bacterial emboli in association with the lesion suggests that they may be etiologically related to similar processes in other parts of the body.

The above example of hemorrhage in the mucosa of the alimentary canal has seemed of especial interest, not only for its possible value in explaining the etiology of the lesion here and elsewhere, but as an interpretation of the findings in Autopsy No. 185, an abstract of which is appended below. There a hemorrhagic lesion in the wall of the urinary bladder led to rupture and brought the patient to the surgical clinic of the hospital.

Autopsy No. 185.

A white female, aged 46 years, was admitted to the New Haven Hospital on January 4, 1919, complaining of “cough and headache.” Five days previously she had a “cold” that she was able to “break up” with quinine and aspirin. The “cold” recurred two days ago, and since then she has had “frequent chills, aches all over, and feels weak.” Her family and past histories were unimportant.

Physical examination on admission showed congestion of the pharynx. Below the inferior angle of the scapula on the right, there was dullness, bronchovesicular breath sounds, and a few fine râles. The examination was otherwise negative. Three days later the signs in the lungs disappeared. The next day, after an attack of coughing, she complained of something having “burst” within her abdomen and of generalized abdominal pain. A diagnosis of ruptured bladder was made and 1,400 cubic centimeters of bloody urine were withdrawn by catheter. Immediate operation was decided upon and the bladder was found a hand’s breadth above the symphysis pubis; the posterior wall was very thin and presented a tear extending from the trigone upward in the mid line for 7 centimeters. Fully 500 cubic centimeters of clotted blood and urine were removed from the pelvis, but there was no marked evidence of peritonitis. A permanent mushroom catheter was placed in the urethra, and the tear was sutured. The abdomen was closed with provision for drainage. The patient was returned to the ward in doubtful condition.

Her temperature at entrance was 104°F., and it fell by lysis to 99°F. just before operation. After the operation it fell to 97°F., and in a few hours rose to 99°F. Thirty-six hours after operation she had a chill lasting ten minutes, and her temperature rose to 105°F. in eight hours, when death occurred. The respirations were thirty per minute until the rupture of the bladder when they rose to forty per minute and corresponding to the final rise in temperature rose to 60 per minute. The pulse ran a parallel curve to the temperature, ranging from 100 to 160 per minute.

The autopsy was held two hours after death, and the essential findings were as follows:—

The body was that of a moderately obese woman. Rigor mortis had not developed, but there was a distinct heliotropic hue of the face and neck. The recent surgical wound between the symphysis pubis and umbilicus was in good condition. The peritoneum was slightly dulled in the lower half of the abdomen, and there was about 100 cubic centimeters of faintly cloudy, blood-tinged, thin fluid in the pelvis. The left pleural cavity contained about 200 cubic centimeters of slightly turbid, amber fluid, but the right side was free from fluid. While the pneumonia had not been prominent clinically, both lungs were found extensively involved by a necrotizing and organizing bronchopneumonia with purulent bronchitis similar to what has already been described. As the lesion of the bladder is the distinctive one in this case, and as the other organs show nothing that has not been described elsewhere, further description will be confined to it.

The wall of the bladder was thin and soft, and grossly the sutured wound appeared in good condition. Posteriorly there was a hemorrhagic zone about 3 centimeters in width most marked beneath the mucosa, but involving all of the coats. The mucosa was superficially ulcerated along this area, and was covered by a thin, patchy, fibrinous exudate. In addition, there were scattered beneath the mucosa several smaller hemorrhagic foci, quite distinct from the larger one.

Microscopically, one striking feature was the erosion of the mucosa, with hemorrhages most marked along the line of rupture but occurring elsewhere in the subjacent tissues. This condition was found in all the sections studied. Another feature was the lack of inflammatory exudate and the very slight attempt to repair the injury, only a very rare polymorphonuclear cell and fibroblast being seen. Sections of the peritoneum showed only a patchy deposit of fibrin with a rare polymorphonuclear cell.

C. MISCELLANEOUS LESIONS

In this series of cases lesions elsewhere in the body are not sufficiently constant or important to merit emphasis. Hemorrhages have been found occasionally in other structures, especially the testes. The usual cloudy swelling of the parenchymatous organs is, of course, marked, and in many cases has been associated with actual cellular necrosis both in the liver and the kidney. Such necroses are usually focal, and occasionally mitotic figures in the cells of the renal convoluted tubules or in the liver may be a similar expression of previous damage. Acute nephritis was not found in our series. The swollen liver cells often show the bile canaliculi clearly, and this appearance may be associated with a variable degree of jaundice which has been found frequently, although the explanation of the jaundice is, in all probability, an hemolysis of the red cells caused by the infecting microorganisms. The only other lesion encountered and of sufficient importance to mention, has been the congestion of the membranes of the brain and a swelling of the cerebral substance, in all probability dependent upon edema. One example of purulent meningitis was encountered. The dilatation of the right side of the heart with a greater or lesser degree of splanchnic engorgement is such a common feature in acute pulmonary diseases that it is hardly worthy of detailed discussion.

FIG. XXXVI. AUTOPSY NO. 133. A SMALL ABSCESS IN AN EDEMATOUS BAND OF INTERLOBULAR CONNECTIVE TISSUE. ]

FIG. XXXVII. AUTOPSY NO. 114. ILLUSTRATES AN UNUSUAL ANATOMICAL PICTURE IN INFLUENZA—AN EXTENSIVE FIBRINOPURULENT PLEURISY. THE BRONCHIAL LYMPH GLANDS ARE PROMINENT ON ACCOUNT OF THE HEMORRHAGIC INFLAMMATORY PROCESS WHICH HAS INVOLVED THEM. ]

A striking feature of influenza is the occurrence of abortion in cases complicated by pregnancy. Of the ninety-five cases included in this report, twenty-seven were women of whom three died undelivered (three months, six months, term), three had suffered complete abortion (one, three months, and two, six months), and one (six months) was in process of abortion. It is not our purpose to discuss the relation between pregnancy and this complication. Here it is desirable simply to point out that, although in the non-complicated cases of influenza, pregnancy does not influence the course of the disease, if pneumonia supervenes, the mortality for the mother, as well as for the child, is definitely increased (57, 148, 164).

A specific placental lesion would be difficult, indeed, to establish since hemorrhage is a part of the normal process of placental separation. However, the hemorrhagic lesion of influenza seems a plausible explanation for the frequency of abortions in this disease.

Summary.

The most important extrapulmonary lesions in influenza are those of the hematopoietic and the vascular systems. The first are typical of a general non-suppurative, inflammatory process, and are characterized in the majority of cases by a picture not unlike that encountered in typhoid fever, although the hyperplasia of the lymphadenoid tissues, as seen in the latter disease, is not present. The more important lesions are associated with the vascular system; phlebitis and arteritis occur, but are not so frequent as hemorrhages in the skeletal system, in the parenchymatous organs, and in the mucous membranes of the hollow viscera. These hemorrhagic necroses may be etiologically associated with capillary bacterial thrombi.

IV. COMPARISON BETWEEN THE RESPIRATORY LESIONS OF INFLUENZA AND THOSE INITIATED BY THE INHALATION OF POISONOUS GASES

Immediately preceding the advent of the influenza epidemic in New Haven, there had been completed in this laboratory the experimental studies of the effects of a large number of different toxic gases upon the respiratory tract. This was begun with the support of the Bureau of Mines, and subsequently, after the formation of the Chemical Warfare Service, the work received the support, not only of this branch of the Army, but also of the Surgeon General’s Office. Exceptional opportunities for animal experimentation were offered. Every stage of the inflammatory process in the respiratory tract was studied, from the most acute, a few hours after the exposure of the animal to a high concentration of gas, to the very chronic types that resulted from sublethal concentrations and led to lesions encountered at the sacrifice of the animals many months later.