There is no doubt that diphtheria is a specific contagious disease, and that it is, at least finally, a constitutional one ; but opinions differ as to whether the malady is constitutional from the first. The more commonly received opinion is, perhaps, that the affection is always a constitutional one, and that the throat lesion is its chief local expression, analogous to the rash of specific fevers. Some pathologists are, however, inclined to believe that the lesion of the mucous membrane is at first a purely local ailment resulting directly from contact with the poison, just as the pustule. of small-pox may be excited locally by the process of inoculation. Accord ing to this view the constitutional suffering would be of the nature of sep ticmmia, the blood being directly contaminated by absorption of a specific virus from the diseased spot. The well-known influence of a catarrhal state of the fauces in increasing the susceptibility of the individual to the diptheritic contagion seems to lend support to this theory.
Symptoms.—As in all forms of zymotic disease, the onset of the illness is preceded by a period of incubation. This period may occupy only a few hours or may last for a week or eight days before the symptoms of in vasion are noticed.
Cases of diphtheria may be divided, according to the gravity of the symptoms, into the mild, the severe, and the malignant forms.
In the mild form of the disease the child is a little feverish, often com plains of headache, and is unwilling to swallow solid food. The fever is slight, the temperature often rising to between 101° and 102°, seldom higher. (Thus, in the case of a little girl, aged two years and ten months, temperature : second day, morning, 99.4° ; evening, 101.6°. Third day, morning, 99.4° ; evening, 101°. After this date the temperature was normal both morning and evening.) In all cases there is some languor and loss, of spirits with a certain expression of distress in the face. Even in slight cases a little change is noticed in the quality of the voice, which becomes nasal or throaty. Vomiting is not common in the mild form, although in the severer cases it may be a frequent and distressing symptom. Some times the symptoms are even less marked. The child may take his food as usual without any complaint, and only show his indisposition by a cer tain pallor of face and want of sprightliness in his look.
When the throat is examined, the fauces are found to be red and swollen, but more on one side than on the other ; the uvula is increased in size ; and on one or both tonsils a gray or fawn-colored, tough-looking opaque patch will be seen, usually occupying the anterior face. The patch may be a continuous layer of some consistence, or may
be composed of spots of false membrane scattered over the surface. These, however, soon unite so as to form a more coherent coating. In all cases the glands at the angles of the jaw are tender and enlarged ; but this symptom is often not marked until the end of the second or the beginning of the third day.
In the mild form the temperature often falls after three or four days. The general symptoms continue trilling ; the child takes food with appe tite ; and unless he attempt to swallow solid food, deglutition is accom panied by little distress. The false membrane may spread a little along the soft palate; but usually remains limited in extent. Very quickly it be gins to separate at the edges and then becomes detached. In rare cases, after spontaneous separation of the first patch of membrane a second ap pears upon the mucous surface. I have known this to happen in one in stance. The sore throat may be accompanied by some discharge from the nose. .Usually, at the end of a week or ten days the child is convalescent from the throat affection ; but it still remains to be seen whether he will escape after ill-consequences.
In the severe form the disease may be severe from its intensity or dan gerous from its seat. Thus, it may spread widely over the pharynx and be accompanied by signs of serious constitutional suffering ; or may attack the larynx and, although limited in extent, produce the gravest conse quences from interference with the respiratory process (membranous croup).
Severe pharyngeal diphtheria may begin with the mild general symp toms which are common in the slighter form which has been described ; or may be accompanied by much more serious phenomena. Thus, the child complains of difficulty of swallowing and of racking headache ; his face is pale and distressed ; fever is high ; vomiting may occur on any at tempt to take food ; and the patient may even be convulsed. The false membrane in the throat is thick and generally coherent. It spreads rapidly over the tonsils, the soft palate, and the back of the pharynx ; often pene trates into the nasal foss, or forms patches on the cheeks, the gums, and the lips. The odor of the breath is soon noticed to be fetid or even gan grenous ; and a thin offensive discharge escapes from the nostrils and forms crusts at the openings of the nares.