Reduction of Blood Platelets in Purpura. 



97 



interpret such instances as indicating that the purpuric plasma 

 contains dissolved platelet (thromboplastic) substance and that 

 the deficiency of platelets in purpura is frequently due to a destruc- 

 tion of these cells. It becomes evident therefore that the explana- 

 tion for the fact that we may have a normal coagulation time in 

 purpura, in spite of greatly diminished platelet count, can be 

 accounted for on the ground that there is no true lack of platelet 

 substance; the deficiency is merely apparent, the total amount of 

 platelets in solution and in suspension equalling the normal. In 

 some cases inhibiting coagulative factors also play a role. 



In cases of purpura there is frequently a hemolytic substance 

 in the plasma which renders it exceedingly difficult to find com- 

 patible donors for transfusion. It is possible that this lytic 

 substance is associated with the function of the spleen. We know 

 such to be the case in pernicious anemia and hemolytic icterus in 

 regard to the destruction of the red cells. It has furthermore 

 been established that the removal of the spleen, both in man and 

 in animals, brings about a definite increase in the number of 

 blood platelets. It would therefore seem worthy of trial to 

 perform a splenectomy, immediately preceded by a blood trans- 

 fusion, in severe cases of purpura where extreme therapeutic 

 measures — repeated transfusions — have been resorted to in vain. 



TABLE I. 



Showing Difference of Effect of Prolonged Centrifugation and of the 

 Addition of Hirudin Solution upon Normal and Purpuric Plasma. 



Type of Case. 



Coagulation Time. 



After 15 Min. 

 Centrifugation. 



After Prolonged 

 Centrifugation. 



No. of Hours 

 Centrifugalized. 



Coag.Time after 

 Adding Hirudin 

 Solution. 



(I). 



Normal 



1(4). 



f(s). 



Purpura gj; 



1(8)1 



Hemophilia (9) 



9 

 4 

 1 



14 



26 

 10 

 18 



30 



14 

 26 

 11 



94 



30 

 28 



16 

 21 



