HUNTOON AND HUTCHISON 927 



since early in the disease the cases should be treated intravenously as well as intra- 

 spinally. 



In the third or meningeal stage, specific serum therapy by intradural administra- 

 tion is necessary. Two avenues for the introduction of serum have been commonly 

 used — lumbar puncture and through the fontanel into the ventricles. Lumbar punc- 

 ture is performed with little danger, and serum given by this route is effective in a 

 considerable percentage of cases, particularly in those treated early. Ventricular 

 puncture is apparently harmless, and it is a comparatively easy method in infants. 

 After closing of the ventricle trephining is necessary. To these methods must now be 

 added a third avenue, namely, cistern puncture. The discouraging results often noted 

 in late cases are sometimes due to spinal subarachnoid or ventricular block, which 

 prevents serum introduced by lumbar puncture from reaching the cerebral meninges. 

 Puncture of the cisterna magna gives the optimal route for overcoming the effects 

 of spinal block. It has been shown to be a safe and efficient procedure. Some 

 authors go as far as to recommend cistern puncture as the routine method, discarding 

 lumbar puncture as less efficient, but probably the more conservative attitude is to 

 use the cistern puncture only in cases which do not show satisfactory progress under 

 lumbar therapy. In the presence of spinal subarachnoid block, cistern puncture is 

 not only indicated but imperatively demanded. 



It should be noted that, after intraspinal injection in the treatment of meningitis, 

 the individual becomes actively sensitized to horse serum, and if a recrudescence of 

 the attack occurs, such cases must not be treated by intravenous injection. 



The influence of specific therapy in the treatment of meningitis as compared 

 with the results of the non-specific treatment of the pre-serum period is well 

 covered in Blackfan's monograph.' The average mortality for meningococcus men- 

 ingitis untreated by serum is given as from 60 to 80 per cent, whereas the mortality 

 rate for serum-treated cases reported by different observers ranges anywhere from 

 16 to 37 per cent. The beneficial effects of serum treatment are especially noted in 

 cases of children under two years of age, in which age group the mortality is nearly 

 100 per cent without serum treatment. These striking results mark anti-menin- 

 gococcic serum as the most efficient of the anti-bacterial sera. 



ANTI-PLAGUE SERUM 



Sera have been produced against the plague bacillus {Pasteurella pestis) — the 

 causative organism of bubonic plague. Their chief value depends upon their anti- 

 bacterial properties. The plague bacillus produces a small amount of exotoxin and 

 some sera have shown limited antitoxic value, but this property is apparently unim- 

 portant. Potent sera contain opsonins or bacteriotropins, agglutinins, and possibly 

 bacteriolysins. As with other antibacterial sera, its best therapeutic results are ob- 

 tained when given as early as possible and in large doses. 



Preparation. — Owing to the dangers connected with handling the plague organism, com- 

 mercial laboratories are required to use only non-virulent strains. Horses are immunized by 

 injecting cultures intravenously in gradually increasing doses. The serum recovered can be 

 shown to contain various antibacterial immune bodies, but the direct potency test on rats is 



'Blackfan, K. D.: loc. cit. 



