Skin Tests with Filtrates and Vaccines of Staphylococcus Aureus

produced by staphylococcus filtrates apparently demonstrating an exotoxin comparable to that obtained with the filtrates of Streptococcus hemolyticus of scarlet fever,2 erysipelas,3 puerperal sepsis,4 and septicemia.5 Heinbecker and Irvine Jones 6 have since reported similar reactions in man in a group of 77 Eskimos, and Greenebaum and Harkins 7 in 19 cases of chronic staphylococcus pyodermia. In the following report the first observations were extended, in a larger number of normal persons, and also in patients affected with staphylococcus infections, testing the filtrates and vaccines of numerous strains of Staphylococcus aureus isolated from active pyogenic lesions. The method described by the Dicks 2 with streptococcus toxin was used. Fifty freshly isolated strains of Staphylococcus aureus were obtained from various lesions as abscesses of breast, kidney, and hand, carbuncles, furuncles, otitis media, and from other sources as indicated in table 1. They produced typical golden pigment which varied in intensity; on blood agar nineteen strains showed hemolysis. Both the hemolytic and nonhemolytic strains produced potent filtrates which, however, varied considerably in potency. The staphylococci were grown in broth prepared with Witte's peptone Ph 7.4, and incubated at 37 C. for 4 days. The broth was filtered through Berkefeld filters. The sterile filtrates were diluted from 1: 250 to 1: 2000; tests were made by intradermal injections of 0.2 cc. into the middle portion of the forearm; controls were made on the opposite arm with the heated filtrate. Reac-