Lesions 383 



human medicine, and do not always occur in those brought in 

 contact with the lower animals. The fungi may enter the or- 

 ganism through the mouth and pharynx, through the respira- 

 tory tract, through the digestive tract, or through wounds. 



The invasion has been known to take place at the roots 

 of carious teeth, and is more liable to occur in the lower 

 than in the upper jaw. Israel reported a case in which 

 the primary lesion seemed to occur external to the bone 

 of the lower jaw, as a tumor about the size of a cherry, 

 with an external opening. Two cases of the disease 

 observed by Murphy, of Chicago, began with toothache and 

 swelling of the jaw. A few cases of dermal infection are 

 recorded. Elsching * has seen a case in which calcified 

 actinomyces grains were observed in the tear duct. 



When inhaled, the organisms enter the deeper portions 

 of the lung and cause a suppurative broncho-pneumonia 

 with adhesive inflammation of the contiguous pleura. After 

 the formation of the pleuritic adhesions the disease may 

 penetrate the newly formed tissue, extend to the chest- 

 wall, and ultimately form external sinuses; or, it may 

 penetrate the diaphragm and invade the abdominal organs, 

 causing interesting and characteristic lesions in the liver 

 and other large viscera (see Fig. 113). 



Lesions. The degree of chemotactic influence exerted 

 by the organism seems to depend upon the tissue affected, 

 upon the peculiarity of the animal, and upon the virulence 

 of the organism. When an animal is but slightly suscepti- 

 ble, and especially when the tongue is affected, the disease 

 is characterized by the formation of cicatricial tissue 

 "wooden tongue." If, on the other hand, the animal be 

 highly susceptible and the jaw-bone affected, suppuration, 

 with the formation of abscesses, osteoporotic cavities, and 

 sinuses, are apt to be noticed. This form of the disease is 

 called "lumpy jaw" in cattle. 



Before the nature of the affection was understood it 

 was confounded with diseases of the bones, especially osteo- 

 sarcoma. 



From the tissues primarily affected the disease spreads 

 to the lymphatic glands, and eventually to the lungs. Israel 

 has pointed out that certain cases of human actinomycosis 

 begin in the peribronchial tissues, probably from inhalation 

 of the fungi. 



* "Centralbl. f. Bakt. u. Parasitenk.," xvm, p. 7. 



