100 



Scientific Proceedings (98). 



Of this number 43 per cent, gave positive test for arsenic, averaging 

 .036 m.mg. of arsenic per c.c. 



Group B — 23 cases in which the intravenous injection of 0.6 

 arsphenamine was followed in half an hour by complete drainage 

 of spinal fluid. One hour later a second lumbar puncture was 

 done to determine if complete drainage tended to increase the 

 amount of arsenic penetrating. In 32 per cent, arsenic penetrated 

 in half an hour ; in 23 per cent, it had penetrated following drainage. 

 Quantitatively, the average amount of penetrations in the first 

 half hour was .009 and after one hour, .0043 m.mg. per c.c. 



Group C — Of 5 cases in which complete drainage was done one 

 hour before the intravenous injection of 0.6 arsphenamine none 

 showed arsenic penetration an hour afterwards. 



Group D — In 40 cases the patient's own serum was injected 

 into the subarachnoid space followed in 6 to 8 hours by an intra- 

 venous injection of 0.6 arsphenamine. Of the spinal fluid ob- 

 tained one hour later 92 per cent, showed positive test for arsenic. 

 Quantitatively, these cases averaged .103 m.mg. per c.c. 



From these figures it is apparent that the simple withdrawal of 

 spinal fluid either before or after the intravenous administration 

 of arsphenamine does not increase the amount of arsenic which 

 penetrates into the spinal fluid. 



On the other hand after the patient's own serum has been 

 injected into his subarachnoid space, the injection of arsphenamine 

 was followed by the appearance of arsenic in the cerebrospinal 

 fluid in the great majority of the cases and the average amount of 

 arsenic obtained was far greater than after simple arsphenamine 

 injections. That the injection of serum caused meningeal irri- 

 tation was showed by the subsequent cell count of 100 to 2,300 

 cells per cm. From these observations it may be surmised that 

 the therapeutic results obtained in the Swift Ellis reaction depend 

 in part, at least, upon a lowering of the barrier between the blood 

 and spinal fluid owing to the meningeal irritation. This lowering 

 allows arsenic freer access to the spinal fluid — a result which is in 

 accord with Flexner's observations on the penetrations of anti- 

 bodies. 



Conclusion. — The intradural injection of serum 8 hours before 

 the intravenous injection of arsphenamine definitely increases 

 the penetration of arsenic into the cerebrospinal fluid. 



