Faecal samples from 50 pigeons all originating from different lofts were screened for the presence of macrolide and lincosamide (ML)-resistant isolates of Streptococcus gallolyticus and Enterococcus columbae by plating the samples onto selective media. Sixty-eight ML-resistant E. columbae strains were recovered from the faecal samples of 29 animals. Two of these samples also harboured ML-resist...

Phage-encoded virulence genes of group A streptococci were detected in 10 (55.6%) of 18 isolates of group C streptococci that had caused bovine mastitis. Bovine isolates carried other genetic determinants, such as composite transposon Tn1207.3/F10394.4 (100%) and antimicrobial drug resistance genes erm(B)/erm(A) (22.2%), linB (16.6%), and tet(M)/tet(O) (66.7%), located on mobile elements.

Pathogens in the genus Campylobacter are the most common cause of food-borne bacterial gastro-enteritis. Campylobacteriosis, caused principally by Campylobacter jejuni and Campylobacter coli, is transmitted to humans by food of animal origin, especially poultry. As for many pathogens, antimicrobial resistance in Campylobacter is increasing at an alarming rate. Erythromycin prescription is the t...

Streptococcus pneumoniae isolates (N = 31,001) were collected from patients with community-acquired respiratory tract infections during the PROTEKT US surveillance study (2000-2003). While the macrolide (erythromycin) resistance rate remained stable at approximately 29%, the prevalence of resistant isolates containing both erm(B) and mef(A) increased from 9.7% in year 1 to 16.4% in year 3, with...

Sir, Haemophilus parasuis is the causative agent of Glässer’s disease, characterized by fibrinous polyserositis, polyarthritis and meningitis in pigs, which causes considerable economic losses in the swine industry. Macrolide antibiotics inhibit bacterial protein synthesis by binding to the 50S ribosomal subunit. Although macrolides are widely used in the treatment of Gram-positive infections, ...

Twenty-two unrelated erythromycin-resistant anginosus group strains (3.2% resistance rate) were assessed for mechanisms of resistance. Streptococcus anginosus accounted for 16 of the 22 isolates. Fifteen isolates harbored the erm(B) gene. The erm(TR) and the mef(E) genes were carried by two isolates each. In three isolates, none of these resistance genes was detected by PCR.

Mechanisms for tetracycline and macrolide resistance in 54 isolates of erythromycin-resistant Streptococcus agalactiae were analyzed by PCR. The erm(B), erm(A), and mef(A) genes, either alone or in combination, were detected in all the erythromycin-resistant isolates. The tet(M) and tet(O) genes were responsible for tetracycline resistance. Random amplification of polymorphic DNA indicated diff...

BACKGROUND Macrolide resistance in Streptococcus pneumoniae (S. pneumoniae) is a worldwide problem. AIMS The aim of this work was to analyze the phenotypes, genotypes, and clonal relatedness among macrolide-resistant S. pneumoniae strains isolated from various clinical specimens in our hospital. STUDY DESIGN Cross-sectional study. METHODS 80 non-duplicate S. pneumoniae strains were analyz...

We conducted population-based surveillance for pneumococcal bacteremia within a 5-county region surrounding Philadelphia from October 2001 through September 2008, the period following introduction of the seven-valent pneumococcal conjugate vaccine. Erythromycin resistance increased from 14.7% in 2001-2002 to 20.3% in 2007-2008, while the resistance rate to penicillin (MIC, ≥2 μg/ml) decreased f...

INTRODUCTION Resistance to macrolides, lincosamides and streptogramins B (MLS(B) antibiotics) in staphylococci may be due to modification in ribosomal target methylase encoded by erm genes. The expression of MLS(B) resistance lead to three phenotypes, namely constitutive resistance (cMLS(B)), inducible resistance (iMLS(B)), and resistance only to macrolides and streptogramins B (MS(B)). The iML...