Waksman — 182 — Actinomycetes 



newer theory, the mouth, including the oral cavities and pyorrhea pus, 

 the pharynx, and other organs such as the tonsils, is the normal carrier 

 of the infectious agent. 



In addition to the common abdominal, pulmonary, and cervico- 

 facial, forms of actinomycosis, other types exist, such as cardiac in- 

 volvements and subcutaneous infections. Myocardial and pericardial 

 forms of actinomycosis may be considered clinically as cases of rheumatic 

 heart disease (81). Two cases of actinomycotic endocarditis, due to 

 aerobic forms, have been studied in detail by Wedding (496). Gins 

 and Paasch (137) found that most of the clinical cases suspected of 

 being actinomycotic turned out to be due to other causes; only 1 out of 

 14 cases was caused by a true actinomyces. 



Aerobic Actinomyces Infections:— In addition to the anaerobic 

 forms of actinomycosis, many infections in man and in animals are 

 caused by aerobic species of actinomycetes. "Streptothricosis" or "no- 

 cardiosis" should always be differentiated from "actinomycosis," espe- 

 cially in lung infections. 



BosTROEM (44) reported the discovery of an aerobic type of Actino- 

 myces, designated as A. hominis, but, as pointed out above, his conclu- 

 sions were erroneous. The significance of these results has frequently 

 been questioned (170) for several reasons: (a) saprophytic aerobic ac- 

 tinomycetes occur abundantly as air contaminants; (I?) Bostroem suc- 

 ceeded in making only relatively few isolations; (c) he, as well as others, 

 failed to obtain infection in experimental animals and in cattle; and 

 (d) he made his isolations from the common "lumpy jaw" type of 

 bovine actinomycosis known to be caused by an anaerobe, A. hovis. 



It may be mentioned here, in passing, that Bostroem's A. hovis and 

 several of the forms accepted by Baldacci are probably species of Strep- 

 tomyces. 



The aerobic nature of the actinomycetes causing certain infections, 

 such as that of Madura foot spoken of as Mycetoma fedis and occurring 

 largely in the tropics, is well established. The pus contains white or 

 yellowish granules, similar to the sulfur granules of the lumpv jaw, from 

 which as many as 13 strains of Nocardia have been isolated. The 

 causative agent studied by Vincent (438) is considered to be the most 

 common. The organism is readily cultivated and is now recognized 

 as Nocardia madurae. These aerobic organisms cause specific types of 

 mycetomas; their multiplicity has no bearing whatsoever on the early 

 erroneous work of Bostroem on the etiology of "lumpy jaw," as brought 

 out above. 



Among the aerobic forms, the acid-fast actinomycetes are particularly 

 significant. Infections of the lungs and of the skin are frequentlv 

 produced but no clubs are formed at the extremity of the hyphae in 

 infected tissues. The aerobic tvpes are cultivated much more readily 

 than the anaerobes and are pathogenic to laboratory animals. The or- 



