Studies on tuberculosis in dogs, and on a case of human tuberculosis contracted from a dog

Abstract

1. Apparently this is the first case on record in which tuberculosis of the skin in man was contracted from an infected dog through a wound. The infection probably occurred when handling the heavily infected lymph nodes and serous membranes of dog No. I at post-mortem. 2. In view of the rather obscure nature of the lesions, and the fact that this case was complicated with nervous distemper, tuberculosis was not suspected in this dog, until diagnosed histologically. 3. The nodule on the finger, which remained completely circumscribed, was successfully excised approximately three months after infection. 4. In the two dogs with natural tuberculosis the infection was of the nature of an incomplete primary complex in the abdominal cavity. 5. Although large doses of tubercle bacilli were injected into two; dogs intravenously, the disease was much milder, and less widespread than in the two natural cases. 6. In all the dogs clusters of macrophages and epithelioids dominated the picture in the lesions, whereas neutrophiles appeared to play an insignificant part. There was no evidence of Langhans giant cells and calcification, and in the liver, spleen and lungs no caseation was observed. 7. In view of the morphology of the tubercle bacilli, the nature of their growth in culture media, and of their behaviour in rabbits, it was concluded that the human type of organism was involved in all these cases.