BACKGROUND Despite pneumococcal antibiotic resistance rates in excess of 25%, macrolides remain first-line agents for the treatment of community-acquired pneumonia. METHODS Prospective, population-based surveillance was conducted to identify cases of pneumococcal bacteremia in Toronto and Peel, Canada, between 2000 and 2004. "Macrolide failures" were defined as cases of bacteremia occurring d...

We conducted a case-control study of adults with bacteremic pneumococcal pneumonia to identify factors associated with macrolide resistance. Study participants were identified through population-based surveillance in a 5-county region surrounding Philadelphia. Forty-three hospitals contributed 444 patients, who were interviewed by telephone regarding potential risk factors. In multivariable ana...

Different patterns of resistance against commonly used macrolide, lincosamide, and streptogramin antibiotics were found in Clostridium perfringens of animal origin. The patterns were designated as (i) macrolide-lincosamide-streptogramin group B generalized resistance, (ii) macrolide-lincosamide generalized resistance, (iii) macrolide-lincosamide inducible resistance, and (iv) macrolide-lincosam...

There was a high percentage of macrolide resistance in Mycoplasma pneumoniae clinical isolates in China. The genetic relatedness of macrolide-resistant M. pneunomiae strains was investigated using the multilocus variable-number tandem-repeat assay (MLVA). Among 152 M. pneunomiae isolates, the 137 macrolide-resistant strains were clustered into 15 MLVA types, indicating that the high macrolide r...

Macrolide resistant Streptococcus pneumoniae has been increasing rapidly in Southeast Asia. A review from 2000 through 2011 at Charoenkrung Pracharak Hospital that evaluated drug resistance to erythromycin found S. pneumoniae from 158 of the 390 (40.5%) patients: 3.6% intermediate, 36.9% highly resistant. A significant correlation was found between macrolide resistant S. pneumoniae and penicill...

In vitro susceptibility testing of 2,797 group A streptococcus (GAS) isolates demonstrated that telithromycin was fully active against all macrolide-susceptible strains and among 80 of 115 macrolide-resistant GAS expressing the M phenotype. Telithromycin resistance was identified in 2 of 45 strains expressing the inducible macrolide-lincosamide-streptogramin B phenotype and four of nine isolate...

Current Japanese clinical practice involves the usage of large amounts of new macrolides such as clarithromycin and roxithromycin for the treatment of diffuse panbronchiolitis, Helicobacter pylori and Mycobacterium avium complex infections. In this study, the phenotypes, genotypes, and macrolide resistance mechanisms of macrolide-inactivating Escherichia coli recovered in Japan from 1996 to 199...

Key words (‒)-exiguolide - macrolide marine natural product macrocyclization ring-closing metathesis transannular cyclization

The activity of a new ketolide, ABT-773, was compared to the activity of the ketolide telithromycin (HMR-3647) against over 600 gram-positive clinical isolates, including 356 Streptococcus pneumoniae, 167 Staphylococcus aureus, and 136 Streptococcus pyogenes isolates. Macrolide-susceptible isolates as well as macrolide-resistant isolates with ribosomal methylase (Erm), macrolide efflux (Mef), a...

BACKGROUND Haemophilus influenzae HMC-C with high-level macrolide resistance after multi-step selection by clarithromycin reverted spontaneously and became hypersusceptible to macrolides. OBJECTIVE Determination of macrolide resistance mechanism(s) in hypersusceptible and hyperresistant strains. METHODS The presence of macrolide efflux in the strains was studied by radioactive erythromycin ...