Relative potency of telithromycin, azithromycin and erythromycin against recent clinical isolates of gram-positive cocci.
A ketolide (telithromycin), an azalide (azithromycin) and a macrolide (erythromycin) were tested against 2,733 isolates of gram-positive cocci gathered from 11 different medical centers. Telithromycin was active against erythromycin-resistant staphylococci that were susceptible to clindamycin but was not active against those that were resistant to clindamycin. More than 99% of all Streptococcus pneumoniae and Streptococcus pyogenes isolates were susceptible to 1 microg/ml of telithromycin including erythromycin- and azithromycin-resistant strains. Telithromycin was not only more potent than azithromycin against macrolide-susceptible strains, it was also active against most macrolide-resistant strains. Although the prevalence of macrolide-resistant pneumococci increased from 19% to 27% between 1997 and 1999, macrolide resistance among other gram-positive cocci did not change substantially in that 2-year period.
Barry
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AL
The Clinical Microbiology Institute, Wilsonville, OR 97070, USA. cmi@hevanet.com
Fuchs
P C
PC
Brown
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SD
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017963:Azithromycin / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D004917:Erythromycin / Q000494:pharmacology*; D006095:Gram-Positive Cocci / Q000187:drug effects* / Q000302:isolation & purification*; D006801:Humans; D048628:Ketolides; D018942:Macrolides; D008826:Microbial Sensitivity Tests; D011336:Probability; D012680:Sensitivity and Specificity
D000900:Anti-Bacterial Agents; D048628:Ketolides; D018942:Macrolides; D004917:Erythromycin; D017963:Azithromycin; C106791:telithromycin