202 STRONG AND TEAGUE. 



sometimes be encountered in the sputum. While in the mi- 

 croscopical examination of the sputum Gram's stain is a very 

 valuable aid in arriving at a diagnosis of the organism, never- 

 theless, Gram-negative bacilli have been encountered in the 

 sputum, which proved later not to be plague bacilli. However, 

 usually if the sputum is blood-stained, from the microscopical 

 examination, with the aid of Gram's stain, there is no difficulty 

 in arriving at a diagnosis, since the plague organism is usually 

 present in such very large numbers. In the later stages of the 

 disease, involution forms are commonly encountered in the 

 sputum. The organisms are constantly found in great abundance 

 up to the time of death. 



BACTERIOLOGICAL EXAMINATION OF THE BLOOD. 



In the early stages of the disease, cultures from the blood are 

 frequently negative. Sometimes, however, the organism could 

 be cultivated from the blood from twenty-four to forty-eight 

 hours before death, and it could always be obtained from 

 the blood a few hours before death. In many instances the 

 bacteria are present in very large numbers in the blood, so 

 that a diagnosis can often be made from a simple, microscopical 

 examination. In no other disease is so marked a bactersemia 

 present. In the early stages of the disease, cultures from the 

 blood should be made in bouillon, as much as 1 cubic centimeter 

 of blood being employed. The agglutination test is of no value 

 in making a diagnosis, as the course of the disease is too acute 

 and the patient has succumbed before the agglutinins appear in 

 demonstrable quantities. The reaction of the deflection of the 

 complement is also not to be recommended for the same reason ; 

 the examination of the sputum and blood for the presence of 

 the bacillus gives much greater and more valuable information. 

 In cases where no necropsy is permitted and a post-mortem bac- 

 teriological diagnosis is advisable, microscopical examination of 

 material, obtained by lung puncture with a syringe, may often 

 be conclusive of pneumonic plague. Bacillus pestis being present 

 in the microscopical preparation, in enormous numbers, in pneu- 

 monic-plague cases. 



