PUEPURA HEMORRHAGICA 163 



PURPURA HEMORRHAiQIOA 



Purpura hemorrhagica is a pathological state of the 

 animal organism characterized by the appearance of hem- 

 orrhages into the subcutaneous and submucous tissues, 

 in company with infiltration of these tissues with serum, 

 and in some cases desquamation of parts of the integu- 

 ment. It is said to be an infectious, but not a contagious, 

 disease. At one time it was presumed to be contagious. 



The disease, from a veterinary standpoint, may almost 

 be termed more correctly a sequel. Purpura hemor- 

 rhagica in veterinary practice occurs almost always as 

 a sequel to some other infectious, debilitating disease. 

 The most common of these is influenza. Other cases 

 follow an attack of strangles, or a case of distemper. A 

 number of diseases seem to possess the faculty of so dis- 

 arranging the animal organism that purpura hemor- 

 rhagica supervenes. Just what this disarrangement of 

 vital phenomena must amount to, is not easy to judge. 

 Occasionally purpura hemorrhagica wiU follow an attack 

 of influenza of ordinary grade, while another case that 

 has been much more serious will not be followed by this 

 sequel. In some instances only very mild or ordinary 

 attacks of distemper have preceded the development of 

 purpura hemorrhagica. To a certain extent this feature 

 strengthens the belief that the disease is infectious, al- 

 though no proof of a speciflc etiology has yet been pro- 

 duced. On account of the usual infectious nature of the 

 disease to which purpura hemorrhagica is a sequel, it 

 becomes a most difficult matter to obtain satisfactory 

 clinical evidence of the specificity of any organisms that 

 might be isolated therefrom. Various streptococci have 

 been blamed for this disease, but it has never been suc- 

 cessfully transmitted by artificial inoculation with such 

 cultures. 



