Susceptibility of pathogenic Nocardia to erythromycin and acetylspiramycin and their inactivation

Abstract

The susceptibility of five species of pathogenic Nocardia including 91 strains to erythromycin (EM) and acetylspiramycin (A-SPM) was studied. Inactivation of EM and A-SPM by these pathogenic Nocardia was also tested. Among these Nocardia species, Nocardia nova was found to belong to the most sensitive group, and Nocardia brasiliensis was resistant to both EM and A-SPM. The susceptibility of Nocardia asteroides varied depending on the strain. Nocardia farcinica and Nocardia otitidicaviarum were resistant, but both species are more sensitive to EM than A-SPM. All N. brasiliensis tested inactivated EM as well as A-SPM, and the possible structure of the inactivated product is discussed. No inactivation products were obtained from N. nova.