296 THE MENINGOCOCCUS GONOCOCCUS GROUP 



obtained containing but little fibrin. Small numbers of cocci were 

 found within the polymorphonuclear leukocytes. Flexner 1 and Von 

 Lingelsheim and Leuchs 2 have reproduced the essential lesions of 

 cerebrospinal meningitis in monkeys by the subdural injection of 

 suspensions of the organisms. The organisms were recovered in pure 

 culture at autopsy. 



The evidence of the etiological relation of the meningococcus to 

 cerebrospinal meningitis in man is essentially the common, almost 

 constant demonstration of meningococci in the cerebrospinal fluid 

 and exudates antemortem, and from the tissues of the brain and cord 

 postmortem. It must be remembered that other organisms can 

 produce essentially the same lesions, however. The nature and extent 

 of the lesions observed in fatal cases varies somewhat with the time 

 which elapses between the onset of symptoms and death. The rapidly 

 fatal cases frequently exhibit intense congestion of the membranes 

 of the cord and brain; usually a fibrinopurulent exudate forms, 

 more extensive as a rule at the base of the brain but readily demon- 

 strable in the spinal fluid obtained by lumbar puncture. According 

 to Westenhoffer, 3 there is commonly a swelling of the tonsils and 

 pharynx in the early stages of the disease; middle ear involvement 

 is comparatively frequent. It is probable that the organism passes 

 from the nose and nasopharynx through the lymphatics to the base 

 of the brain. The accessory sinuses of the nasal cavity appear to be 

 inflamed in a majority of cases, particularly during the initial clinical 

 period of the disease. There is a thickening of the meninges in those 

 cases which run a more chronic course, frequently with considerable 

 distention of the ventricles. Intracranial pressure is usually a promi- 

 nent symptom. The organism has been isolated from the blood by 

 Jacobitz, 4 Dieudonne, 5 Elser, 6 Elser and Huntoon, 7 the latter in 25 

 per cent, of their large series of cases. 



Immunity and Immunization. Little is definitely known of man's 

 immunity to the meningococcus. One of the surprising results of the 

 intensive study of the epidemic disease is the occurrence of the organ- 

 ism in the nasopharynx in a very considerable number of apparently 

 healthy individuals, chiefly among those in actual contact with 

 patients, less commonly among those not intimately in association 

 with cases but in regions where the disease is epidemic, and rarely 



1 Cent. f. Bakt., 1907, xliii, 99. 2 Klin. Jarhb., 1906, xv, 489. 



3 Berl. med. Gesellsch., 1905, May 17; abstr. Cent. f. Bakt., Ref., 1905, xxxvi, 754. 



4 Munchen. med. Wchnschr., 1905. * Cent. f. Bakt., Orig., 1906, xli, 420. 

 6 Jour. Med. Research, 1906, xiv, 89. 7 Jour. Med. Research, 1909, xx, 371. 



