CEREBRO-SPINAL MENINGITIS log 



before the cultures are incubated : colonies may not appear for 

 three or four days. The colonies are " round, whitish, shining, 

 and viscid-looking, with smooth, sharply-defined outlines." 

 They are usually small in size, but on suitable media may 

 become quite large, 5 millimetres or more in diameter, and 

 when closely packed may become confluent. They are always 

 white or greyish, never yellow. 



The organism dies out very easily, and cultures should be 

 made and put in the incubator as soon as possible after the 

 fluid is withdrawn. If you want to keep a culture alive, trans- 

 plant it at frequent intervals, unless you use some of the 

 special media devised for the purpose. 



As a rule, the diagnosis presents no difficulties, and in any 

 doubtful case lumbar puncture should be made without hesita- 

 tion, as an early diagnosis is of great importance, both for the 

 patient's sake and for that of the public health. Probably a 

 very considerable number of mild cases are missed, and these 

 are not very uncommon. 



We now include "post-basic meningitis " along with cerebro- 

 spinal fever as a manifestation of the meningococcus. Minute 

 differences have been described as occurring in the bacteria in 

 cases of this nature as compared with the epidemic disease in 

 adults, but the organism is a somewhat variable one whatever 

 the source from which it is derived. 



The bacteriological diagnosis is simple. Have ready two 

 or three sterile test-tubes, and some tubes of glycerin agar, 

 g-lucose-glycerin agar, or coagulated blood-serum. Perform 

 a lumbar puncture, and allow the first few drops of fluid to 

 escape. Then let four or five drops flow on to the surface of 

 the medium in one tube, take very much more 2 or 3 c.c. 

 in a second, and then collect four or five more in a sterile test- 

 tube. If the fluid is perfectly clear and not under obviously 

 increased pressure, do not draw off so much the loss of 3 or 

 4 c.c. may cause severe headaches in a healthy person. If it is 

 under pressure, so that it spurts out instead of falling drop 

 by drop, withdraw more, and do not remove the needle until 

 the normal pressure is established, as far as you can judge. 

 Put your culture-tubes in the incubator as soon as you can. 

 If you are visiting a patient at a distance it is a good plan to 

 take a Thermos flask, and use it as an incubator in the manner 

 already described (p. 21); or you may fill a bottle with water 



