Judging from the macroscopic and microscopic study of the animals treated with the liquid, its action upon the tubercular lesions seems to be about as follows: The effect of a single injection upon the lesions is either negative or inconspicuous. But after repeated injections of the preparation the congestion and leukocytic infiltration about the lesions are markedly decreased, the cheesy material resulting from degeneration of the lesions and other degeneration products are in process of absorption, and young connective tissue is being actively produced in the periphery. While these changes are taking place the number of the bacilli is also being reduced until finally they can no longer be detected on microscopic examination.
Hence it appears that while the preparation may lack bactericidal action in vivo powerful enough to destroy all the bacilli at one injection, yet repeated infusions may nevertheless bring about the destruction of all the bacilli and the modification of the tubercular lesion into that of the suspended stage or even into the healed condition. Whether, therefore, the preparation brings about these results directly by killing the bacilli or indirectly by favoring the healing processes of the body, nevertheless it has power to inhibit the growth of or annihilate entirely the bacilli in vivo.
The experiments reported leave no doubt that Liquid D is capable of bringing about the healing of experimental tubercular lesions; but thus far that most important problem in chemotherapeutics, namely, the extent of the cure produced, has not been solved. The experiments indicate that sterility of the tissues as far as microscopic examinations go has been secured; but microscopic examination is not after all an absolute test of sterility.
In order to test this point, emulsions were made of the lungs, liver, spleen, and other organs of Treated Animals 134 and 135 (Table VII), and they were inoculated into the abdominal cavity of guinea pigs. Some of the animals receiving the emulsion developed tuberculosis, and therefore absolute sterility of the treated animals had not been obtained in these instances.
The problem of the destination and distribution of the preparation in the body of the treated animal, as well as its action against the tubercle bacilli, lesions, and the tubercular organs of the infected guinea pigs, is now being studied further with results to be reported at some future time.