256 



Scientific Proceedings (121). 



an acid-fast variety quite different from A. bovis, and there are no 

 clinical reports of the use of iodides in this type of actinomycosis. 

 Nevertheless, because of its constant virulence it is admirably 

 suited for chemotherapeutic experiments, and it was thought 

 desirable to see what influence iodides would have on the course 

 of the infection in guinea pigs. 



The potassium iodide was administered by mouth in aqueous 

 solution. The results are shown in the table below. The first 

 guinea pig was treated with iodides alone; animals 2 and 4 received 

 iodide both previous and subsequent to inoculation; animals 3 

 and 5 are untreated controls to 2 and 4 respectively. 





Guinea 



Guinea 



Guinea 



Guinea 



Guinea 





Pig 1. 



Pig 2. 



Pig 3- 



Pig 4. 



Pig 5- 

























Date. 

























Wt. 



KI, 



Wt. 



KI, 



Wt. 



KI, 



Wt. 



KI, 



Wt. 



KI, 





gm. 



gm. 



gm. 



gm. 



gm. 



gm. 



gm. 



gm. 



gm. 



gm. 



Jan. 4 



743 



0.12 



838 



0.25 







654 



0.01 







Jan. 6 



695 



0.25 



790 



0.25 







622 



0.25 







Jan. 9 



675 



0.25 



743 



0.25 



1012 



0 



620 



0.25 













(inoculated) 



(inoculated) 











Jan. 11 ... . 



650 



0.25 



625 



0.25 



965 



0 



595 



0.25 







Jan. 12 ... . 







died 



died 











Jan. 13 



608 



0.25 











565 



0.25 







Jan. 16 ... . 



580 



0.25 











543 



0.25 







Jan. 18 



572 



0.25 











539 



0.25 





0 















(inoculated) 



(inoculated) 



Jan. 20 ... . 



580 



0.25 











555 



0.25 



560 



0 



Jan. 21 ... . 



562 



0.25 











500 



0.25 





0 



Jan. 23 ... . 















438 



0.25 



485 



0 



Jan. 24. . . . 



600 



0.25 











died 



died 



It will be seen from the above that the treated animals suc- 

 cumbed simultaneously with the controls; and that the iodide 

 itself, while given in relatively large doses, was not sufficient to 

 hasten death. 



In vitro it was found that both A. gypsoides and A. asteroides, 

 while retarded, still grew in broth containing 10 per cent, of potas- 

 sium iodide. 



It is clear, then, that potassium iodide has no specific action 

 on this type of Actinomyces, and if it has any clinical value, it is 

 due, as in sporotrichosis, not to an action on the parasite itself, 

 but because of its action in stimulating the formation of granula- 

 tion tissue. With A. gypsoides the course of the disease is too 

 rapid to demonstrate this latter point in the guinea pig. 



