The excitable frame of childhood portrays more vividly the exacerbations and remissions which, even in adult age, are in greater or less degree observable in a case of continued fever ; and in them the remission becomes so marked, that for a time the disease seems almost to be gone. In truth, the prominence of this one symptom is no sufficient reason for separating this disease from the endemic fever of adults; and there is nothing to show that infantile remittent may not arise even from the infec tion of typhus. The great question in diagnosis is, how to dis tinguish this, generally one of the more unimportant diseases of infancy, from the much more dangerous malady known as acute hydrocephalus. The same rule must be followed as in the study of continued fevers in adults ; our conclusion must rest more on negative than on positive evidence. We have positive evidence of an acute febrile disease ; we seek for negative evidence that there is not inflammation of the head, the chest, or the abdomen. /The investigation of the,se points will occupy our attention at a futufe period ; and in the consideration of acute hydrocephalus reference will be made to the points of resemblance and differ ence, in so far as they can throw light upon the discrimination of these two diseases, which are unfortunately oft•an mistaken for each other.
§ 3. disorder is characterized by an irritation or inflammatory condition of the mucous membrane of the lungs, implicating also that of the flares and the conjunctiva3; but, super added to this, and constituting its essential feature, is the lassitude and exhaustion of fever. A common e,atarrh, or an attack of bronchitis, it is now the fashion to call influenza. In scientific diagnosis they ought to be distinguished; still, cases must oe,cur in which these different diseases so merge into each other, as to render it difficult, or even impossible. Thus, in an enfeebled constitution the least disturbance may provoke symptoms of general derangement, with fever of an asthentic type, closely allied to influenza; exactly as more severe disease may in the same constitutions cause typhoid symptoms, or symptoms resembling typhus. The determination will be much aided by observing whether the attack occur as a solitary instance, or whether similar cases are numerous at the same time.
It is unnecessary to enter much into detail, with regard to the history and the symptoms. Whatever is true of common continued fever in its milder form, is likely to be true of this disorder, bearing in mind the great diatinc tion, that in the one the mucous membrane of the bowels is the subject of a peculiar affection, and in the other the mucous membrane of the lungs is the principal seat of morbid action. The history points out its recent commence ment, even when supervening upon previous ailment. The general symptoms indicate a febrile state ; the aspect of the patient is more or less depressed; his sensations lead him to complain of a sense of lassitude and general dis comfort, and of cough, tightness of chest, &c., such as are usually present in
catarrhal affection. The chest symptoms are those of acute bronchitis.
Influenza differs from continued fever with superadded bronchitis, chiefly in the greater prominence of the symptoms of irntation of the mucous mem brane of the lungs, and the affection of the nose and eyes, as well as in the comparatively milder character of the fever ; but this is often only a question of degree.
§ 4. Epidemic Chdera.—This frightful disorder, which has come to us from the tropics, and has visited us so frequently of late years, is dassed among the fevers, chiefly on account of the in creasing conviction that it is one of the acute blood diseases, and the evident febrile reaction after recovery from the stage of col lapse. It must be admitted, however, that in very many instances the fever, as such, is very slight in intensity, as compared with the previous depression; in others it is a formidable event, and not unfrequently the cause of the fatal termination. One cha racteristic, which must not be lost sight of, is its epidemic influence ; though we cannot exactly trace the manner of its propagation, it clearly follows the general laws of all epidemics —such, for example, as typhus, the commonest and best known of those of this country.
The history of the case may ultimately be the means of our learning its mode of propagation, as it has already served to determine that its cause is simply an atmospheric influence floating about over our heads. In diagnosis it is of little service, except so far as it may preserve us from paying too much regard to the presence of collapse, as indicating cholera, when there is any other antecedent cause of exhaustion. Collapse is, in reality, only an accident, which may coexist with any condition of extreme depression—e.g., the colliquative diarrhcea of phthisis.
The general symptoms in the commencement of cholera are very different from those commonly seen in fever. is cold and clammy ; the pulse feeble and not frequent; the tongue cold, moist, and not much coated ; the stools remarkably copious, pale, and free from odor ; the urine suppressed ; there is almost always severe vomiting; and the excessive thirst is such as naturally results from the enormous discharges from the whole of the alimentary canal. As the disease proceeds to collapse, the symptoms increase in intensity, the coldness of the skin and its blueness or lividity become most striking; the pulse imper ceptible; and the stools and vomit assume the characters of a thin, colorless fluid, resembling rice water. In reaction the skin sometimes remains cold for several days, and is, perhaps, never hot and dry, as in ordinary fever ; the tongue becomes more coated ; the pulse slowly returns, and is frequent and feeble ; the diarrhcea ceases; thirst abates ; and in favorable cases the urine, at first scanty and albuminous, is gradually restored to its normal condition. When this secretion is not re-established soon after reaction commenced, the issue will probably be un favorable.