Page:Encyclopædia Britannica, Ninth Edition, v. 7.djvu/268

250 DIPHTHERIA regarding the pathology of diphtheria, the real nature of the malady still appears to be undetermined. By some it is regarded as primarily a blood poison, the local mani festations being secondary and not essential, while others hold, and this is the view now largely maintained by Con tinental authorities, that diphtheria is at first a local disease, the constitution becoming secondarily affected or poisoned from the local affection. This latter view receives support both from experiments on inoculation of the disease in animals, and from the discovery in the diphtheritic mem branes and surrounding tissues, as well as in the blood and other fluids of persons suffering from diphtheria, of the lower forms of vegetable organism (bacteria, micrococci, <kc.), which are supposed to be the infecting agents both in the local affection and in its general constitutional effects. "Whether this be the correct explanation of the disease, or whether as is held by many, these organisms are to be looked upon merely as accompaniments or complications of the affection, not present in all cases, the following facts appear to be made out respecting diphtheria : 1. That it is a disease communicable both by infection and by contagion. 2. That grave constitutional disturbance is a constant and prominent symptom of diphtheria. 3. That certain important consequences or, as they are termed, sequelae are apt to follow diphtheria, particularly some forms of paralysis. These points, moreover, serve to distinguish this disease from croup, which, although in some cases presenting cer tain features of resemblance to diphtheria, differs from it in being a merely local inflammatory affection. See CKOUP. As already observed, diphtheria has frequently appeared as an epidemic. It is probably more common in a sporadic form (single cases). It is sometimes endemic in certain localities where the hygienic conditions are bad ; and there is ample evidence to show that air or water contaminated with decomposing animal matter may readily cause an out break of diphtheria. The influence of climate, weather, and condition of soil appear to be inappreciable. When the disease has broken out in a dwelling it is apt to spread not merely by direct contagion, but apparently also through the air of apartments, this being notably the case in over crowded habitations. The contagiousness of diphtheria is very marked, and has unhappily been often exemplified in the case of physicians, who have fallen victims to the disease from inoculation with its morbid products when cauterizing the throats or performing tracheotomy in those suffering from it. Children appear to be on the whole rather more liable to diphtheria than adults : and although the most robust people may be attacked, those whose health is weakened by any cause are specially predisposed. One attack of diphtheria appears to afford no immunity from others. It must be observed, however, that the mere existence of a sore throat accompanied with some amount of membran ous exudation does not constitute diphtheria, as is often erroneously supposed by non-medical persons, who are apt to fancy they have had diphtheria several times from having suffered from what is a comparatively simple complaint. The diagnosis can only be reliably made by a medical man. Cases of diphtheria differ as to their intensity from the mildest forms, which resemble an ordinary catarrhal sore throat, to those of the most severe character (such as the gangrenous form), where the disease is hopelessly intract able from the first. In general the symptoms at the commencement of an attack of diphtheria are comparatively slight, being those commonly accompanying a cold, viz., chilliness and depres sion. Sometimes more severe phenomena usher in the attack, such as vomiting and diarrhoea. A slight feeling of uneasiness in the throat is experienced along with some stiffness of the back of the neck. When looked at the throat appears reddened and somewhat swollen, particularly in the neighbourhood of the tonsils, the soft palate, and upper part of pharynx, while along with this there is tenderness and swelling of the glands at the angles of the jaws. The affection of the throat spreads rapidly, and soon the characteristic exudation appears on the inflamed surface in the form of greyish-white specks or patches, in creasing in extent and thickness until a yellowish-looking false membrane is formed. This deposit is firmly adherent to the mucous membrane beneath or incorporated with it, and if removed leaves a raw, bleeding, ulcerated surface, upon which it is reproduced in a short period. The appear ance of the exudation has been compared to wet parchment or washed leather, and it is more or less dense in texture. It may cover the whole of the back of the throat, the cavity of the mouth, and the posterior nares, and spread downwards into the air passages on the one hand and into the alimen tary canal on the other, while any wound on the surface of the body is liable to become covered with it. This mem brane is apt to be detached spontaneously, and as it loosens it becomes decomposed, giving a most offensive and charac teristic odour to tha breath. There is pain and difficulty in swallowing, but unless the disease has affected the larynx no affection of the breathing. The voice acquires a snuffling character. When the disease invades the posterior nares an acrid, fetid discharge, and sometimes also copious bleeding, takes place from the nostrils. Along with these local phenomena there is evidence of constitutional disturbance of the most severe character. There may be no great amount of fever, but there is marked depression and loss of strength. The pulse becomes small and frequent, the countenance pale, the swelling of the glands of the neck increases, which, along with the presence of albumen in the urine, testifies to a condition of blood poisoning. Unless favourable symptoms emerge death takes place within three or four days or sooner, either from the rapid extension of the false membrane into the air passage, giving rise to asphyxia, or from a condition of general collapse, which is sometimes remarkably sudden. In cases of recovery the change for the better is marked by an arrest in the extension of the false mem brane, the detachment and expectoration of that already formed, and the healing of the ulcerated mucous mem brane beneath. Along with this there is a general im provement in the symptoms, the power of swallowing returns, and the strength gradually increases, while the glandular enlargement of the neck diminishes, aud the albumen disappears from the urine. Recovery, however, is generally slow, and it is many weuks before full con valescence is established. Even, however, where diphtheria ends thus favourably, the peculiar sequelae already mentioned are apt to follow, generally within a period of two or three weeks after all the local evidence of the disease has disappeared. These secondary affections may occur after mild as well as after severe attacks, and they are principally in the form of paralysis affecting the soft palate and pharynx, causing difficulty in swallowing with regurgitation of food through the nose, and giving a peculiar nasal character to the voice. There are, however, other forms of paralysis occurring after diphtheria, especi ally that effecting the muscles of the eye, which produces a loss of the powei of accommodation and consequent impairment of vision. There may be, besides, paralysis of both legs, and occasionally also of one side of the body (hemiplegia). These symptoms, however, after continuing for a variable length of time, almost always ultimately disappear.

In the treatment of diphtheria regard must be had both