DIFFERENTIAL DIAGNOSIS 145 



§ 124. Differential diagnosis. It is important not to 

 confuse anthrax with a number of non-specific disorders and 

 accidental causes of death. The suddenness of the attack, and 

 in very virulent cases, the short duration of the disease may 

 tend to the mistaking of it for poisoning, cerebral apoplexy, 

 pulmonary congestion, heat apoplexy, death from lightning, or 

 acute gastro-intestinal inflammation. The affection known as 

 corn-stalk disease is not infrequently taken for anthrax and 

 vice versa. In all of these cases the doubt following the post- 

 mortem can be easily settled by a bacteriological examination 

 which, with genuine anthrax, will reveal the presence of Bac- 

 terium anthracis. It is believed by those who have dealt most 

 with anthrax, that the specific organisms are always in the 

 circulating blood before death. The putrefactive organisms 

 that resemble Bacterium anthracis morphologically do not 

 appear in the cutaneous blood as quickly after death as they 

 do in the organs. 



There are, however, certain specific diseases from which 

 anthrax must be differentiated. The most important of these 

 are symptomatic anthrax (black leg), malignant edema, and 

 septicemia hemorrhagica. Rabies is not infrequently taken 

 for anthrax. If the diagnosis cannot be determined by the 

 anatomical changes (which can be relied upon only in some- 

 what typical cases) the positive diagnosis can be made only 

 with the finding of the anthrax bacteria. In animals just 

 dead, where decomposition has not begun, these organisms can 

 usually be found in properly stained cover-glass preparations 

 made directly from the blood or ti.ssues. After decomposition 

 begins to take place, a putrefactive organism, that is not easily 

 distinguished from that of anthrax, often appears in the tissues. 

 It is, therefore, necessary in such cases to resort to culture 

 methods before a positive statement can be made. As the 

 bacilli of malignant edema and symptomatic anthrax are 

 anaerobes, they will not develop in aerobic cultures, such as 

 on slant agar or in bouillon. The bacterium of septicemia 

 hemorrhagica, being a small oval organism, is easily told 

 from that of anthrax. It is important to recognize the possi- 



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