Resistance to Macrolides and Related Antibiotics in <i>Streptococcus pneumoniae</i>

Resistance to erythromycin in Streptococcus pneumoniae was first detected in 1967 in the United States and subsequently worldwide (11, 20). The corresponding mechanism was rapidly identified as ribosomal methylation, which had been primarily reported as being responsible for erythromycin resistance in staphylococci (44). Further spread of resistance was then noted in a few countries, such as France, where hospitals observed a sharp increase in the proportion of resistant pneumococci, which reached approximately 20% in 1984 (16). This trend was observed several years before the emergence and spread of penicillin resistance in pneumococci in France. Recently, an increasing number of countries have noted changes in the evolution of macrolide resistance. In some of them, such as the United States, increased incidence has been correlated with the emergence of a new mechanism of erythromycin resistance—efflux (39). This review is devoted to the mechanisms responsible for resistance to macrolides and related antibiotics in pneumococci.