638 INFECTION AND IMMUNITY. 



of the Langhans type. The lungs show lobular 

 or more extensive consolidation. 



The lymph glands show little involvement in 

 blastomycosis ; it is believed that metastases usu- 

 ally take place through the blood stream, which 

 may depend on the large size of the organisms. 

 On the other hand, there is marked lymphatic 

 involvement in coccidioidal granuloma, and it is 

 probable that the liberation of minute endospores 

 favors lymphatic metastasis. Pathologically, the 

 two diseases seem to be differentiated somewhat 

 by the fact that coccidioidal granuloma presents 

 a greater degree of necrosis and caseation than 

 blastomycosis, and the lesions in the former bear 

 a closer resemblance to tuberculosis than do those 

 of blastomycosis (Hektoen). The differences, 

 however, seem to be in degree rather than in kind, 

 indicating a certain lack of correspondence in the 

 pathogenic properties of the organisms concerned. 

 infection The skin infection occasionally follows slight 

 traumatism, while in other instances no predispos- 

 ing condition is known by the patient. The occur- 

 rence of cutaneous lesions in crops has been noted, 

 and suggests that in some instances they may orig- 

 inate as embolic foci from a pulmonary lesion 

 which later heals or becomes latent. In the sys- 

 temic infection the primary lesion appears to be 

 in the lungs in most cases, from which the blood 

 and other organs, including the skin, may be in- 

 vaded. Pulmonary oidiomycosis simulates pul- 

 monary tuberculosis. In extensive involvement of 

 the lungs the organisms may be demonstrated in 

 the sputum. 



