DIPLOCOCCUS INTRACELLULARIS MENINGITIDIS 377 



causes epidemic cerebrospinal meningitis in man. Ostertag found 

 cocci very much like those of Johne; they are Gram negative and 

 closely resemble the organism causing the human disease. The 

 organism of Ostertag, when inoculated subdurally into horses, 

 produced a more or less typical attack of cerebrospinal meningitis. 

 Wilson and Brimhall, in cases of cerebrospinal meningitis in horses 

 and other domestic animals, found both cocci of the type of the 

 Jaeger- Weichselbaum organism and of FrankePs pneumococcus. It 

 appears, therefore, that cerebrospinal meningitis in the horse, like 

 cerebrospinal meningitis in man, may be caused by more than one 

 bacterium; the etiology, however, of the disease in equines is not 

 yet satisfactorily cleared up and further investigations are necessary. 



Cerebrospinal meningitis has also been occasionally found in 

 cattle, sheep, and swine. The description of the disease in these 

 animals is still very fragmentary. 



Johne has named his organism Diplococcus intracellularis equi. 



DIPLOGOGGUS INTRACELLULARIS MENINGITIDIS. 



This organism, first seen by Weichselbaum and later carefully 

 studied by Jaeger, is generally the cause of cerebrospinal meningitis 

 in- man. It is a biscuit-shaped diplococcus, and frequently occurs 

 in large numbers in the protoplasm of pus corpuscles of the fibrino- 

 purulent exudate found at the convexity and at the base of the brain 

 in human cerebrospinal meningitis. The diplococcus stains well with 

 the ordinary watery anilin stains, but is easily decolorized when 

 treated by Gram's method. Pure cultures can generally be obtained 

 from cerebrospinal fluid, drawn with aseptic precautions. Of this 

 fluid 1 to 2 c.c. is inoculated into blood serum or glycerin-agar tubes. 

 Pus in cerebrospinal meningitis can be obtained by spinal puncture. 

 This consists in the introduction of a strong hypodermic needle, 

 4 to 8 cm. long, attached to an all-glass (Luer) large hypodermic 

 syringe, into the spinal canal, about 1 cm. from the middle line and 

 between the third and fourth lumbar vertebrae. The diplococci of 

 cerebrospinal meningitis grow in the incubator at blood temperature 

 only. They develop around surface colonies with an opaque yellowish- 

 brown centre having a flat, thin periphery; the edges may be circular 

 and straight or dentate. Subcutaneous inoculations into laboratory 

 animals are generally not pathogenic for them, but intraperitoneal and 

 intravenous injections often cause a fatal result in mice and rabbits. 

 Flexner and Joblin have prepared an antimeningitis serum in the 

 horse which has proved an excellent therapeutic agent in the human 

 disease, but it must be injected into the spinal canal in comparatively 

 large doses (15 to 30 c.c.) often repeatedly, and it is necessary each 

 time first to withdraw an equivalent or larger amount of the purulent 

 cerebrospinal fluid. 



