Specific Therapy 393 



easily stained by methylene blue, but not by Gram's method. 

 Another similar organism has been described by Elser and Huntoon.* 



Bacteriological Diagnosis. — In cases with the clinical symptoms 

 of meningitis, the bacteriological diagnosis is of great assistance in 

 determining the correctness of the diagnosis and the nature of the 

 infection. It is accomplished by means of the lumbar puncture 

 (vide supra) and the study of the cerebro-spinal fluid thus secured. 

 Normal cerebro-spinal fluid is clear, that in meningitis is cloudy. A 

 few cubic centimeters of the fluid can be used for culture and in- 

 oculation experiments of as many kinds as are deemed advisable. 

 The remainder is placed in a tube and whirled in a centrifuge. From 

 the sediment, smears are made upon slides and stained by various 

 methods, including Gram's method. If the chief cells appearing 

 in the sediment are lymphocytes, tuberculous meningitis should be 

 thought of and smears stained for tubercle bacilli, and guinea-pigs 

 inoculated. If the cells are polymorphonuclear cells, tuberculous 

 meningitis is usually excluded. If small cocci are found, chiefly in 

 the cells, the next question is their reaction to the Gram stain. If 

 positive to the stain, the pneumococcus should be thought of; if 

 negative to the stain, the meningococcus. If the suspected organ- 

 ism grows readily upon ordinary culture-media, it is not the meningo- 

 coccus; if it grow only in the special media it is probably the men- 

 ingococcus. Finally, the agglutinative test with diluted antiserum 

 may be made to perfect the diagnosis. 



Specific Therapy. — KoUe and Wassermannf carefully studied 

 antimeningococcus sera for specific opsonins, for bacteriotropic 

 substances, and for other evidences of favorable therapeutic action, 

 but came to no definite conclusions. Flexner and Joblingf had 

 better success both in developing the experimental and practical 

 knowledge of the serum. The serum was prepared first with goats 

 and then with horses, the animals being injected with suspensions 

 of the meningococci. The serum is used by injecting it into the 

 spinal canal through a lumbar puncture. The precaution must 

 be taken to permit some of the fluid to escape first, and then re- 

 place it by the antiserum, of which not more than 30 cc. must be 

 injected. Several such injections should be made. Tabulations 

 of the results following the employment of Flexner's serum show a 

 large percentage of recoveries. 



* "Journal of Medical Research," ipog, xx, 377. 



t Loc. cit. 



t "Jour. Experimental Medicine," 1907, ix, p. 168, and 1908, x, p. 141. 



