Without regard to the age of the patient, the dose should be 1000 units for localized pharyngeal diphtheria; with the appearance of toxaemia and in progressive diphtheria, 1500 units; in laryngeal stenosis and ma lignant diphtheria, 2000 to 3000 units. If there is no improvement after twenty-four hours, the injection should be repeated, perhaps in larger doses.
[In America physicians who have had considerable experience with diphtheria advocate the use of much larger amounts, recommending an initial close of 4000 units for moderately severe pharyngeal or nasal diphtheria, if seen early; when laryngeal stenosis exists or if the toxaemia is decidedly evident early in the disease, at least 6000 units should be given; if not seen before the third day S000 or 10,000 units should be given in as concentrated a form as possible; in progressive or toxemic cases another dose of at least 4000 units should be given in six hours and repeated at that interval subsequently until improvement is ob served. Many cases apparently hopeless may thus be saved.—A. I-I.] The injection may be made with any sterilized syringe holding five cubic centimetres. The most suitable sites are those parts of the skin where the connective tissue is loose, like the side of the chest or the ab dominal wall. The location should be cleansed in the usual way, a fold of skin raised and the needle introduced parallel to it far enough so that the point is freely movable in the subcutaneous connective tissue. Before drawing out the needle a small piece of adhesive plaster is placed over the site of injection to prevent the escape of serum and the entrance of infection. Massage of the swelling raised by the injection is superfluous. Very often the area around the puncture is tender for twenty-four hours.
The serum hastens the melting away of the pseudomembrane and prevents a further spread of the local process. It also neutralizes more or less completely the diphtheria toxin which subsequently passes into the circulation from the affected mucous membrane. Clinically this action is noticeable in twenty to twenty-four hours. The picture re sembles that of an accelerated natural recovery. The intoxication does not progress, the general well-being is improved, the fever comes down by lysis or crisis, the blood pressure rises, and the nervous symptoms disappear. Locally, the deposits are at first. cleaner, glistening and then
more prominent as if they were raised a little from their base, sharply demarcated and surrounded by a more or less well defined inflammatory area. On the second clay they look softer and are reduced about one half. On the third day they have wholly disappeared, or perhaps only a small particle remains. If there is a relapse and the injection is repeated, the action is similar to that in the first attack (K. Zucker).
effect of the antitoxin is seen in all cases which live for at least twenty-four hours after the injection, and this effect is espe cially noticeable in the changes in the pseudomembrane. The effect of the serum and recovery are not of the same significance (Wieland), for the serum has no regenerative action on the tissue-cells attacked and destroyed by the toxin before the injection. Recovery is intimately dependent on the amount and intensity of the absorbed toxins, on the point of time at which they enter the body, and on the time of injection and the amount of the antitoxin. If a close of antitoxin proportionate to the severity of the case is injected sufficiently early, recovery may be expected with considerable certainty under certain conditions. These are: (1) that the cases are of mild or average toxicity; in such cases the action of the toxin develops so slowly that the diagnosis and specific therapy are not too late. In severe toxic cases, on the other hand, the toxin may be formed in such quantities and of such activity and in so short a time passing into the circulation, and the individual suscepti bility may therefore be so greatly increased, that injection of the anti toxin even on the first day of the disease may not be able to prevent a fatal intoxication; (2) that the patient is not already weakened by some other disease, for in such cases it needs only a small amount of the toxin, absorbed before the injection of the antitoxin, to cause death; (3) that no septic complications are present, for the action of the specific remedy is only against the specific (diphtheria) poison, but not against other bac terial poisons, as it has not the power to combat any other kind of bac teria. In such cases therefore only partial success is to be expected, to the extent in which diphtheria toxins are taking part in the disease.