414 ACTINOMYCOSIS 



The spreading in the tissues along the lymphatics occurs probably 

 through the filaments which protrude from the rosette cavity at its 

 root and penetrate into the surrounding tissues, in which small bacilli- 

 like segments and spores become detached. They are taken up by 

 the leukocytes, which later wander away and, instead of killing the 

 fungi by phagocytic action, perish themselves in consequence of cell 

 necrosis. The spores set free in this manner form the focus for the 

 formation of new actinomycotic granules or rosettes. The spreading 

 of the infection by continuity depends to a large degree upon the tissue 

 reaction. Where much fibrous connective tissue is formed around 

 the actinomyces granules, they are likely to undergo complete gelatin- 

 ous degeneration with club formation, and to die out. Where there 

 is more tissue necrosis and softening and less fiber formation the 

 ray fungi tend to remain alive, to form new young filaments, and to 

 spread through these extending filaments and their rods and spores. 



Actinobacillosis. Ligniere and Spitz, in 1902, described a disease 

 of cattle in Argentina, which is said to occur sporadically and also in 

 epizootic form. This disease was called actinobacillosis. Its symptoms 

 and pathologic changes are almost identical with those of actinomy- 

 cosis in cattle. The lesions are most commonly found in the sub- 

 cutaneous tissue of the neck; the tongue, however, has been found 

 affected in only 5 per cent, of the cases; changes in the lungs, lymph 

 glands, lymphatics, pharynx, udder, and bones were found even less 

 frequently. The subcutaneous changes consist in diffuse infiltrations 

 with abscess formation which project as round swellings above the 

 surrounding surface. The tumors are generally not very large but 

 of rather moderate size, and only after having existed for weeks and 

 months do they discharge a very tenacious whitish or greenish pus, 

 in which grayish-white granules of the size of a pinhead can be seen. 

 The cavities of the abscesses contain a grayish granulation tissue. 

 The disease, however, more frequently leads to the production of 

 hard, fibrous connective-tissue masses, rather than causing abscess 

 and granulation tissue formation. When the process invades the 

 tongue the picture of the wooden tongw of ordinary actinomycosis is 

 produced. Microscopic examination of the granules found in pus 

 shows them to resemble the rosettes of ordinary actinomycosis. 

 Ligniere and Spitz, however, claim that if the granules are rubbed 

 up in a mortar and inoculated into culture media, a growth of bacilli 

 not much larger than 1 to 1.8 micron long and 0.4 wide is formed. 

 Inoculations of these organisms into cattle are said to have produced 

 lesions like those found under natural conditions. 





