Cross-Sensitivity to Various "Mycins"

Reports about cross-sensitivity among the various "Mycins" are contradictory. Sidi, Hincky, and Longueville^1,2were the first to report cross-sensitivity between neomycin and streptomycin, and vice versa. Calnan and Sarkany³were not able to confirm this fully, although 2 of their neomycin-sensitive patients also reacted to streptomycin. Pirilä and Wallenius⁴and Pirilä and Rouhunkoski^5,6as well as Hjorth⁷reported that a great number of their neomycin-sensitive patients were also sensitive to bacitracin. This, however, is not the experience of others. To clarify these matters we investigated experimentally in guinea pigs sensitization to, and cross-sensitivity between, neomycin, kanamycin, streptomycin, and bacitracin.

Materials and Methods

We set out to sensitize albino guinea pigs, weighing between 400 and 500 gm., in groups of 10, to neomycin, kanamycin, streptomycin, dihydrostreptomycin, and bacitracin. The animals received 4 weekly injections of 5 mg. of the antibiotic mixed with Freund's adjuvant. This technique