138 DIPHTHERIA AND PSEUDODIPHTHERIA. 



the point of inoculation, with the formation of a false mem- 

 brane. Marked congestion of the adrenal bodies, serous or 

 serosanguinolent effusions in the pleural cavities, and swollen 

 spleen. A few of the bacilli may be found at the point of 

 inoculation and in the fluid of the oedema. In the blood and 

 internal organs no bacilli can be found, showing that the 

 symptoms are purely toxic. 



Roux and Yersin have also been able to produce the false 

 membrane giving rise to the disease, by the inoculation of 

 rabbits and guinea-pigs into the mucous surfaces or into the 

 skin, and they have reproduced in animals the characteristic 

 diphtheria paralysis. This paralysis, best seen in the rabbit, 

 usually begins in the posterior extremities and gradually ex- 

 tends over the whole body, death being caused by paralysis 

 of the heart and respiratory organs. 



Different cultures of diphtheria bacilli, though emanating 

 from equally virulent cases of diphtheria, and grown under 

 the same conditions, show at times a great variation in toxicity. 

 The explanation of this has not been as yet satisfactorily 

 given. But this fact we should remember when testing the 

 efficacy of antitoxins in neutralizing the toxins of diphtheria. 



Diphtheria Diagnosis. Clinically it is not always easy to 

 differentiate diphtheria in its early stages from other affections 

 of the throat and nose which are characterized by the pres- 

 ence of exudates. In view of the recent therapeutical advances 

 in diphtheria, it is important that a very early diagnosis be 

 made. For this purpose, accepting the almost unanimous 

 opinions of experts, that diphtheria is due to the presence of 

 diphtheria bacilli in the membranous exudate, boards of 

 health, cities, and hospitals have established a diphtheria 

 service for the purpose of facilitating the early recognition 

 of the disease. In order to carry out this method, a central 

 laboratory with all facilities is established, and in cities a 

 number of supply-depots are located within reach of the 

 practising physician, where the material in complete outfits 

 necessary to make cultures from the throats of suspected cases 

 of diphtheria may be procured. These outfits consist of a blood- 

 serum culture-tube (Fig. 59) made after the formula of Loeffler, 



