CHAPTER XXV 



BACILLUS PSEUDOTUBERCULOSIS GROUP 



THE term " pseudotuberculosis bacillus " is applied to any 

 organism that produces a disease in which nodules resembling 

 those of tuberculosis are formed. The name does not refer to any 

 relationship of the organism to the Bacillus tuberculosis, but 

 simply to the similarity of the lesions produced. These organisms 

 are not acid fast. They all resemble each other in being the cause 

 of chronic caseations and suppurations, particularly of the lymph- 

 nodes. 



This group of organisms, including the B. pseudotuberculosis, 

 B. lymphangitidis ulcer osa, and B. pyogenes bovis, is in need of 

 careful revision, for the species limits are not well understood. 

 These organisms all resemble the diphtheria bacillus somewhat, 

 particularly in pleomorphism, shape, and staining characters. 

 None, however, are known to produce any toxins. 



Bacillus pseudotuberculosis 



Synonyms. Bacillus pseudotuberculosis ovis; Mycobacterium 

 pseudotuberculosis; Bacillus tuberculosis murium; bacillus of 

 Preisz. 



Diseases Produced. Caseous lymphadenitis in sheep, and 

 similar infections in the mouse and rarely in cattle. 



Organisms differing morphologically from the tubercle bacillus, 

 but causing somewhat similar lesions in the body, were first noted 

 by Malassez and Vignal in 1883. Charrin and Roger, in 1888, 

 described nodules in the liver and spleen of guinea-pigs, caused by 

 organisms that were not acid fast. Nocard, in 1889, studied an 

 epizootic among rabbits caused by a similar organism. Preisz 

 and Guinard, in 1891, reported pseudotuberculosis in sheep, and 

 in 1894 Preisz published an extended account of the disease. 

 In the United States Norgaard, in 1899, published an account of 



