CHAPTER XIII 



ACTINOMYCOSIS 



The subject of actinomycosis is difficult to present in a logical 

 manner because of the large number of types of pathogenic actino- 

 mycetes and the multiplicity of diseases they cause on the one hand, 

 and because of errors in identification on the other. Lebert is credited 

 with the first report of the disease in man in 1857. In 1876 Bollinger ^ 

 described the disease in cattle and in 1877 Harz named the organism 

 Actinomyces bovis. A part of the material Bollinger studied was 

 bovine actinobacillosis which is caused by a Gram-negative bacillus 

 and at that time it was not differentiated from actinomycosis. The 

 knowledge of the characteristics of A. bovis was based only upon its 

 appearance in tissues until 1891 when Wolff and Israel "^ isolated it 

 in pure culture, described it adequately, and showed that it was an 

 anaerobe. Unfortunately, in this same year, Bostroem also attempted 

 to obtain cultures and, using aerobic methods of cultivation, failed 

 to grow .4. bovis but isolated in a few of his cultures an aerobic actino- 

 mycete (Streptomyces) which he erroneously described as A. bovis. 

 It is generally considered now that this organism was a chance con- 

 taminant. The Bostroem organism is of a type common in soil and 

 vegetation and gave rise to the popular misconception that the 

 pathogen occurs in nature on straws and that it is transmitted from 

 such material to animals and man. Actually A. bovis has never been 

 found on vegetation except in rare cases when the awns of grasses 

 and similar material have been found as foreign bodies in lesions 

 about the jaws. Even in these cases it is highly probable that the 

 fungus was not present on the awns until they were contaminated in 

 the oral cavity, where A. bovis is known to be commonly pres- 

 ent ®' ^"' "'°' ■'^' "^' ^'*' ^® 



A. bovis is difficult to isolate and maintain in culture, but the 

 Bostroem contaminant grows readily and is easily transferred in 

 culture. As a consequence, few laboratories or culture collections 

 have maintained cultures of A. bovis, but a strain of Bostroem's 

 aerobic fungus, once deposited in a culture collection under the erro- 

 neous name, is maintained easily and remains indefinitely as a source 



of confusion. 



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