Antibacterial Effect of Whole Blood upon Strains of Staphylococci Sensitive and Resistant to Penicillin ∗ †

Abstract

Discussion and Conclusions

Strains of staphylococcus adapted to grow in the presence of the sulfonamides are just as invasive as other strains which are inhibited in growth by the sulfonamides. Whole, human blood has no greater bactericidal action on the sulfonamide-resistant strains than on the sulfonamide-sensitive strains. Strains of staphylococcus adapt themselves to grow in the presence of penicillin at a slower rate and to a lesser degree than is apparent for the sulfonamides. And probably of considerable clinical importance is that an increas d resistance to penicillin is accompanied by the development of strains which are more susceptible to the bactericidal action of whole blbod, and possibly to the other defense mecbanisms of the host.