PIIARYNGEAL, OR TONSILLAR, CASES.
—These often present difficulties in di agnosis, but a full consideration of all the factors in any case will usually lead to a correct judgment. The most diffi cult cases are the milder ones, where there is little or no membrane and the constitutional symptoms are slight. The question of exposure should be consid ered in every case. Children gathered in hospitals or asylums or attending schools are especially exposed to diph theritic infection, and in them any form of sore throat may justly be looked upon with suspicion. So far as the catarrhal form of diphtheria is concerried, even with a history of exposure, there is no way of making a diagnosis of diph theria in the early stages except by bac teriological cultures. The after-course of some of these cases—in which we may see invasion of the larynx, broncho-pneu monia, nephritis, or paralysis—may show them to have been diphtheria, when no suspicion has previously been enter tained.
When diphtheritic membrane is pres ent in the throat, it usually presents cer tain definite characters. It begins as a thin, translucent deposit upon one or both tonsils. Gradually or rapidly it becomes thicker, and assumes a white, gray, or grayish-green, brown, or—in malignant cases—black color, and ex tends peripherally to cover a larger and larger area. It is firmly attached to the mucous membrane or underlying tissues and cannot be easily rubbed off. If re moved by force, a raw, bleeding surface is left, and in a very short time the mem brane is reproduced in its original or even a greater extent. Beginning upon the tonsils, the membrane rapidly ex tends to other parts: the lateral walls of the pharynx, the fauces, or uvula. Upon any of these parts the membrane presents the same characters as at the original site. This extension of the mem brane is most characteristic of diph theria. The only cases in which we are likely to see such extension of a pseudo diphtheritic membrane are the throat in flammations accompanying other infec tious diseases, measles, small-pox, and— most of all—scarlet fever. The great majority of the membranous throat af fections seen in the early stages of these diseases are produced by the action of streptococci or staphylococci. When a similar process is seen as a late complica tion of infectious diseases, it is more probably true diphtheria.
The early temperature in diphtheria is not usually high; it is, in fact, gen erally lower than in pseudodiphtheria, with an equal amount of membrane. A high temperature in the beginning is, therefore, an indication that the case is not diphtheria. On the other hand, the prostration is greater in diphtheria than in pseudodiphtheria. The pulse is feebler; the patients look and feel sicker than they do when suffering from pseudodiphtheria. The presence of a nasal discharge of the character de scribed as belonging to nasal diphtheria and marked swelling and tenderness of the cervical lymph-nodes help to dis tinguish some cases in the early stages. Later we look for the development of the typical complications or sequehe of diphtheria: invasion of the larynx, broncho-pneumonia, albuminuria, or some of the manifold forms of paralysis. The occurrence of any of these processes is usually sufficient to make the diag nosis certain, although it is not impos sible that any of them except the paraly sis may be seen in cases of pseudodiph theria. Paralysis subsequent to throat inflammation is seen only in diphtheria. Pseudodiphtheria is, in the great ma jority of cases, a milder disease and of shorter course than diphtheria. As al ready remarked, the primary throat in flammation of scarlet fever most closely resembles true diphtheria. In fact, in every case where diphtheria is suspected, the possibility of scarlet fever must be borne in mind and examination made for the eruption. Oftentimes it will be found at the very first examination; al any rate, a brief delay will suffice to de termine the question, as the eruption of scarlet fever so. quickly follows the ini tial symptoms. It may even happen that the throat symptoms of measles may simulate diphtheria, and especially if the eruption be delayed for a number of days. Here, however, there is rarely any membrane at all, and the presence of conjunctivitis, with the simple mucous discharges from nose and throat, should be sufficient to prevent mistake. Fur thermore, if Koplik's observation of the occurrence of an eruption of peculiar bluish-white specks upon a. reddish background on the mucous membrane of the mouth previous to the appearance of the regular skin exanthem of measles be proved correct, it should furnish another basis for differential diagnosis.