Mycobacterium avium strains susceptible to clarithromycin and azithromycin contain mutants resistant to these macrolides with a frequency of 1.1 x 10(-10) to 1.2 x 10(-6). Cross-resistance between clarithromycin and azithromycin was demonstrated with mutants selected in the laboratory as well as with resistant strains isolated from patients. The susceptibility-resistance patterns of the macroli...

Fluoroquinolones, sulfonamides and macrolides were analyzed in soil samples collected from suburban areas in Tianjin, China. Fluoroquinolones were the predominant class of antibiotics. The mean total concentration of fluoroquinolones (33.56 μg/kg) was 30-fold higher than one of macrolides, which were the second dominant class antibiotics. Sulfonamides showed the lowest level in soil. The spatia...

In Europe, antimicrobial resistance has been monitored since 1998 by the European Antimicrobial Resistance Surveillance System (EARSS). We examined the relationship between penicillin nonsusceptibility of invasive isolates of Streptococcus pneumoniae and antibiotic sales. Information was collected on 1998-99 resistance data for invasive isolates of S. pneumoniae to penicillin, based on surveill...

Ketolides belong to a new class of semi-synthetic 14-membered-ring macrolides, which differ from erythromycin A by having a 3-keto group instead of the neutral sugar L-cladinose. The ability of these molecules and their L-cladinose counterparts to induce MLS(B) resistance in staphylococci (one strain) and streptococci (two strains) was investigated using a disc agar susceptibility method as wel...

In Europe, antimicrobial resistance has been monitored since 1998 by the European Antimicrobial Resistance Surveillance System (EARSS). We examined the relationship between penicillin nonsusceptibility of invasive isolates of Streptococcus pneumoniae and antibiotic sales. Information was collected on 1998-99 resistance data for invasive isolates of S. pneumoniae to penicillin, based on surveill...