If the view at present generally held, that the complicating pneumonia is de pendent upon the action of streptococci and not upon that of the diphtheria bacillus, itself, and therefore antitoxin. can only indirectly affect its onset or its violence, be true, then the problem of further reducing the mortality of diph theria must depend upon the solution of the prevention and treatment of this complication. At present it is of im portance to watch for signs of its onset and to be prepared to take measures to limit its extension and enable the pa tient to bear the attack. The most malignant cases of diphtheria die within forty-eight hours of the onset of the disease, and even in these we find more or less extensive areas of broncho-pneu, monia. Most of the fatal cases termi nate after five or ten days, the patients being exhausted by the toxmmia of the disease or the pneumonia.
In the more favorable cases improve ment usually begins about the fourth or fifth day. The change is shown in both the blood and the general condition. In the throat the membrane ceases to extend and begins to separate. The separation begins upon the edge of each patch, the separated portions forming loosened tags in the nose or throat, or the membrane may come away en masse in the form of casts of the affected parts.
The surface beneath the membrane is at first raw and bleeding, but is usu ally quickly covered by new epithelium. On the tonsils, however, ulcers are formed, which, healing slowly, leave irregular, depressed areas of cicatricial tissue, giving to the tonsils the ex cavated appearance so often seen after severe diphtheria. With the separation of the membrane the purulent discharge from nose and mouth gradually ceases, but a catarrhal secretion may continue for weeks afterward, such catarrhal secretion still containing virulent ba cilli.
With the change in the local condi tion the temperature gradually falls, the pulse improves, the glandular swellings subside, the dullness or stupor disappear, and at the end of the second or third week the patient is convalescent. The patients are usually left very amemic, and the return to health is likely to be slow.
From time to time we see cases in which the formation of membrane con tinues for two or three weeks, the course of the disease is protracted and recovery correspondingly delayed. In other cases the broneho-pneumonia persists long after the disappearance of all evidences of the diphtheria, and may either cause death from exhaustion or may slowly dissolve.