Among the serous inflammations which complicate or follow scarlet fever, pleuritis is one of the most important. It usually begins in the desquamative stage, and is apt to be suppurative on account of the feeble state of the patient when it commences. It has always, in my practice, been tedious, as all empyemas are, and it does not differ in its clinical history from the idiopathic disease. I have met cases of scarlatinous empyema in which, from opposition of the family or for other reasons, thoracentesis was not performed, and death occurred; others in which this operation effected a cure, and one at least in which the patient recovered by escape of pus through a bronchial tube. The pleuritis is seldom latent, or so masked by the symptoms of the general disease that it is apt to be overlooked. On the other hand, the cough, embarrassment of respiration, and pain referred to the affected side render diagnosis easy.
Dilatation of the heart is common in grave cases of scarlet fever, such cases as are properly termed malignant. It is indicated by a feeble and quick pulse. Acute infectious maladies, especially those of a malignant type and accompanied by high febrile movement, are very apt to cause parenchymatous degenerations in organs, prominent among which is granulo-fatty degeneration of the muscular fibres of the heart. This weakens very much the contractile power of these fibres. But early in malignant cases, probably before the muscular fibres are damaged, the contractile power of the heart is feeble from impaired innervation, the result of the general weakness. Hence this organ, when weakened by structural change and insufficiently stimulated through diminished innervation, may not fully empty itself during the systole, and consequently it becomes dilated. Dilatation of the heart and imperfect contraction of the auricular and ventricular walls are apt to result in the formation of clots in the cavities of the heart; and this appears to be the immediate cause of death in not a few instances. An ante-mortem clot occurring in any of the cavities of the heart necessarily seriously obstructs the circulation, unless it be of small size. Hence the dyspnoea, which may occur perhaps suddenly, and the change of pulse to one of marked feebleness and frequency. Large, firm white clots are most frequently found in the right cavities. They interlace with the chordæ tendineæ, lie even within the auriculo-ventricular opening, and send prolongations into the pulmonary artery and the cavæ. Associated with the white clots are dark, soft clots and fluid blood. The left cavities may be contracted and empty, or they may contain dark, soft clots or white ante-mortem clots. Clots in the left ventricle are sometimes prolonged into the aorta as far as the brachio-cephalic branches, while those in the left auricle may extend to the pulmonary veins. If dilatation of the heart be so great that clots form in its cavities, speedy death is probable. Sometimes a patient passes through scarlet fever and appears in a fair way to recover, when he succumbs to some exhausting sequel distinct from the heart, and at the autopsy the heart is found dilated and containing whitish clots, which are probably ante-mortem, and which hastened death by obstructing the circulation. Under such circumstances this state of the heart is attributable in great measure to the complication which has weakened its contractile power.
The following was a case in point. It occurred in the New York Foundling Asylum:
Case 7.—R. A., aged three years, had scarlet fever, beginning March 23, 1882. The symptoms were favorable at first, but serious complications and sequelæ occurred, which were fatal. The record of April 18th reads: "Appears well nourished, but is anæmic; has otorrhoea; no oedema; skin desquamating; dulness on percussion over upper third of right side of chest, anteriorly and posteriorly; mucous râles and rude breathing over same area; fine râles posteriorly over lower part of left side of chest; pulse 160, respiration 68, temperature 101.4°." April 20th, is feeble and takes nutriment with difficulty; tongue thickly coated; pulse 160, respiration 68, temperature 101.4°. April 26th, condition about the same as at last record, but he is evidently weaker; the lips are ulcerated and fauces still swollen. May 2d, cannot speak distinctly; a brownish, foul-smelling secretion lodges on the spoon used in depressing the tongue; left side of face swollen. On the following night eight convulsions occurred, attended by orthopnoea, and mucous râles in the chest from pulmonary oedema. Diarrhoea supervened and the patient died about midnight. Autopsy: Body moderately wasted and very white, several dark-blue spots on scalp and face from hemorrhages underneath; lips covered with dry crusts; brain of normal appearance; aperture of the larynx narrowed at the chink by infiltration and swelling of the tissues; surface of the vocal cords covered by a thin white film, apparently a fibrinous exudation; tracheal surface hyperæmic; about a drachm of straw-colored fluid in each pleural cavity; right lung wholly adherent by recent exudation of fibrin; left lung also largely adherent. A careful examination showed the presence of broncho-pneumonia in each lung, with considerable infiltration of the walls of the bronchi, and cylindrical dilatation of many of them; cavities of the heart dilated, so that this organ appears much enlarged, and its shape approaches the globular; its apex is rounded or obtuse; transverse diameter of the right ventricle, when its walls were open and drawn apart, was three and one-quarter inches; that of the left ventricle three and a half inches. Similar measurements of the heart of another child of about the same age, believed to be normal, were about one inch less in each direction. All the cavities contain white firm clots along with soft dark clots. Liver of normal size, pale; the outer surface and all cut surfaces are studded with nodules of the size of a pin's head, of a dull, opaque white color. These white spots, examined microscopically by Professor Delafield, are found to be neither tubercles nor gummy tumors, but to consist of polygonal cells, lying in the meshes of the capillary plexus of veins, which are perfectly preserved. He has not observed a similar case. The walls of the gall-bladder are one line or more in thickness, and the gall-duct is pervious. The microscope shows general hypertrophy of the gall-bladder and hypertrophy of its papillæ. The urine removed from the bladder was found to contain albumen and hyaline casts, and a microscopic examination showed a small amount of parenchymatous inflammation. The spleen was somewhat enlarged. Punctate congestion of small areas of gastric surface, no increase of mucus; mesenteric glands uniformly enlarged; jejunum, ileum, and colon exhibited a slightly increased vascularity. The immediate cause of death appeared to be imperfect contraction of the heart and the formation of clots in its cavities, due, apparently to the pleuro-pneumonia as much as, or more than, to the primary disease, scarlatina.3
3 Dr. Goodhart (Guy's Hospital Reports, 1879) reports several interesting cases to confirm his opinion that acute dilatation of the heart is a not infrequent sequel of scarlatinous nephritis, and is the cause of death in some apparently inexplicable cases.
There can be little doubt that nephritis in its milder form is much more common than was formerly supposed. A few years since little attention was given by a large proportion of physicians to the state of the kidneys, and the urine was not examined till dropsy made its appearance, which only occurs in the more severe forms of nephritis and is a late symptom. It is now known that catarrh of the renal tubes frequently occurs in a mild form early in scarlet fever, without causing albuminuria, dropsy, or any notable symptom. It may produce a smoky color of the urine, and the appearance in it of granular epithelial cells, with an increase of mucus, but no albumen. With careful treatment and no exposure to cold, the renal catarrh abates with the decline of the scarlet fever. It is scarcely severe enough to merit the name desquamative, tubal, or parenchymatous nephritis, though it is a mild form of the same pathological state. Steiner states, as the result of many careful examinations of cases, that hyperæmia of the kidneys was always present in those who died early in scarlet fever, and that in a certain proportion of these cases catarrh of the renal tubules was present in addition to the congestion. Even in some who died on the second or third day he found cloudiness of the epithelium in the renal tubes, although the urine had not indicated such a change. The opinion has even been expressed that catarrh of the renal tubes is as common in scarlet fever as that of the bronchial tubes in measles; that is, that it is a uniform element in the disease; but this appears to be an exaggerated statement, for others have failed to find any evidence of renal catarrh in certain cases.
The nephritis which gives rise to symptoms, and therefore interests the practitioner, commonly begins in the declining period of scarlet fever or during the desquamative stage, and is in many instances plainly attributable to exposure to cold or to currents of air. It originates either during this period, or, if it have previously existed as a mild renal catarrh, it now becomes aggravated. Dropsy, which always attracts attention, does not occur till the nephritis has continued for some time.
Why nephritis, with the subsequent dropsy, so frequently occurs after scarlet fever is not fully understood. Rilliet and Barthez attribute it to disturbance of the function of the skin. The fact has long been observed that the kidneys become affected nearly if not quite as frequently after mild as after severe cases. Indeed, the chief danger in mild cases, when the patients are but a short time in bed and are soon allowed to go about, is from the nephritis. Chilling the surface and checking cutaneous transpiration appear to be the immediate cause of this inflammation in a considerable proportion of cases. Therefore, severe attacks of scarlet fever with abundant rash and desquamation, which require the patient to be kept in bed the proper time and in a warm room two or three weeks, appear to be less frequently followed by this renal disease than are milder cases which are more carelessly treated.
The most thorough and minute microscopic examination of the state of the kidneys in scarlet fever which have come to my notice were those by E. Klein, published in the Lond. Path. Soc. Trans., and illustrated by microscopic drawings. It appears from these examinations that the changes in the kidneys are complex, among which we recognize both those of parenchymatous or desquamative nephritis and interstitial nephritis; but we would infer that the interstitial nephritis is mild in degree and quite subordinate, or else confined to portions of the organ, from the fact that so many permanently and fully recover. The following is a resumé of Klein's examinations in twenty-three cases: We conclude from these microscopic researches that the anatomical changes of both parenchymatous and interstitial nephritis are commonly present in greater or less degree in cases of scarlet fever. If they are mild or confined to portions of the kidneys, no symptoms occur; but if they are sufficient in extent or degree to impair the function of these organs, then symptoms, as albuminuria, diminution of urine, etc., appear.
1. Parenchymatous Nephritis, Proliferation of Nuclei, Hyaline Degeneration of Arterioles, the Glomerulo-Nephritis of Klebs.—Klein found increase of nuclei (probably epithelial) upon the glomeruli and hyaline degeneration of the intima of minute arteries, especially marked in the afferent arterioles of the Malpighian bodies. The intima of these vessels was in places so swollen as to resemble cylindrical or spindle-shaped hyaline masses, and cause narrowing of the lumina of the vessels in which this degeneration occurred. Klein observed in some specimens so great hyaline degeneration of the capillaries of the Malpighian bodies that circulation through them was obstructed. In the more advanced or protracted cases this hyaline substance in the glomeruli began to assume a fibrous appearance. Bowman's capsule was considerably thickened. This hyaline degeneration of the Malpighian bodies Klein discovered in the earliest cases which fell under his observation.