A significant relationship between copper resistance (tcrB), glycopeptide resistance (Tn1546), and macrolide resistance [erm(B)] in Enterococcus faecium isolated from pigs was found. The tcrB gene was located closely upstream of the Tn1546 element. However, the continued use of copper sulfate has not been able to maintain high levels of macrolide and glycopeptide resistance.

We found a 13% macrolide resistance in 3,866 Streptococcus pyogenes isolated from tonsillopharyngitis patients; 59% macrolide-resistant isolates were distributed in 5 clones, suggesting the importance of both resistance gene transfer and clonal dissemination in the spread of these organisms. We also report one of the largest collections of telithromycin-resistant isolates.

Staphylococcal isolates were examined for possible macrolide-inducible resistance to telithromycin. All macrolide-resistant isolates demonstrated telithromycin D-shaped zones. This result did not discriminate between resistance due to an efflux mechanism (msrA) or a ribosomal target modification (ermA or ermC). Inducible telithromycin resistance in staphylococci does not appear to be analogous ...

National Ambulatory Medical Care Survey data were used to assess outpatient macrolide prescribing and selection. Conditions for which macrolides are firstline therapy represented 5% of macrolide prescribing. Family practitioners selected macrolides for children more frequently than pediatricians. Macrolides are an important antibiotic stewardship target.

The potentiation of the antiviral activity of acyclovir [9-[(2-hydroxyethoxy)methyl]guanine] by polyene macrolide antibiotics has been studied as a function of the macrolide structure. The 12 polyenes chosen for this study represented the major structural groups of these antibiotics and induced in mammalian cells repairable membrane alterations or irreversible cell damage. The potentiating acti...

Macrolide antibiotics, such as azithromycin and erythromycin, are in widespread use for the treatment of bacterial infections. Macrolides are taken up and excreted mainly by bile. Additionally, they have been implicated in biliary system diseases and to modify the excretion of other drugs through bile. Despite mounting evidence for the interplay between macrolide antibiotics and bile acids, the...

Macrolide-resistant Mycoplasma pneumoniae (MR M. pneumoniae) has been isolated from clinical specimens in Japan since 2000. A comparative study was carried out to determine whether or not macrolides are effective in treating patients infected with MR M. pneumoniae. The clinical courses of 11 patients with MR M. pneumoniae infection (MR patients) treated with macrolides were compared with those ...

The aim of this work was to study and compare macrolide resistance patterns among Streptococcus pneumoniae, Streptococcus agalactiae and Streptococcus pyogenes, to describe the phenotypes of macrolide-lincosamide resistance and to further investigate associations between macrolide resistance and social clustering. Susceptibility data were obtained from 4 clinical microbiology laboratories in Ba...

We determined the macrolide resistance phenotypes of 241 clinical isolates of erythromycin-resistant enterococci (MICs, > or = 1 microg/ml), including 147 Enterococcus faecalis strains and 94 Enterococcus faecium strains, collected from a hospital in Seoul, Korea, between 1999 and 2000. By the erythromycin (40 micro g)-josamycin (100 microg) double-disk test, 93 strains were assigned to the con...

Sir: Several publications report psychiatric symptoms induced by macrolide antibiotics. Clarithromycin and erythromycin used in combination with other treatments, or even in monotherapy, have been reported to produce acute psychoses, manic episodes, and depression. To our knowledge, this is the first report of an association between azithromycin, another macrolide antibiotic, and the initiation...