Endocarditis With Nephritis 



253 



human beings displays two constant factors — injury to the valve 

 and later infection. The injury is usually represented by either 

 congenital valvular heart disease or rheumatic valvular heart 

 disease. The later implantation of green streptococcus on this 

 injury usually takes place through the medium of an infection 

 of the middle ear or throat or some other locality where green 

 streptococci normally breed. In experimental work Rosen- 

 bach recognized these two factors in 1878 and reproduced in- 

 fection in the heart valve after puncture of the valve. Al- 

 though a beginning was made so long ago, and more perfect in- 

 struments have been devised for injuring the valve, no attempt 

 has been made to reproduce the disease completely and glo- 

 merular nephritis of the type which characterizes the disease in 

 human beings has never heretofore been reproduced. All clin- 

 ical efforts to obtain a cure of the disease have failed. It seems, 

 therefore, that we must have the disease reproduced in animals 

 and then thoroughly study its features if we are to expect a 

 cure. 



This work consists in injuring the aortic valve by inserting 

 an appropriate instrument into the left carotid and then, after 

 recovery, the animal is infected by intravenous inoculation of 

 green streptococcus. The inoculated bacteria become implanted 

 at the site of the valve injury and there set up a bacterial vegeta- 

 tion identical with that of human patients. Dogs were used 

 in these experiments. Dogs living 12, 13 and 14 days failed 

 to show any kidney lesion of the glomerular type although 

 large infractions were common. A longer survival of the ani- 

 mal seemed essential for producing the kidney picture. The 

 gross specimens exhibited here and the microscopic specimen 

 showing the glomerular lesion are from a dog which lived 17 

 days. The glomerular lesion consists of partial thrombosis of 

 the tuft with hyaline degeneration and with hemorrhage and 

 infiltration with polymorph, leucocytes. One of the most im- 

 portant results of this work is that we have reproduced a bac- 

 terial infectious disease which is of sufficient duration to per- 

 mit thorough study of many of the unknown factors of infec- 

 tion and immunity. 



