Characterization of MLS_b resistance among Staphylococcus aureus and Staphylococcus epidermidis isolates carrying different SCCmec types

Abstract

Staphylococcus aureus and S. epidermidis are pathogens associated with nosocomial infections (1). Their remarkable ability to acquire antimicrobial resistance limits therapeutic options and may contribute to patient morbidity and mortality (2, 3). MRSA and MRSE present the mecA gene that is located in a staphylococcal chromosome cassette (SCCmec). The most frequent SCCmec types are I, II and III, which are hospital-acquired, and IV, which is community-acquired (2, 4).Macrolide-lincosamide-streptogramin B antibiotics can be used as alternative therapies for staphylococcal infections, but resistance to these drugs has already been observed ( encoded by erm genes, and an ATP-dependent efflux pump conferred by the msr(A) gene (6).In order to characterize MLS b resistance in MRSA and MRSE Brazilian isolates, we analyzed the distribution of erm(A, B and C) and msr(A) genes and the MICs for erythromycin and clindamycin in these isolates and correlated our findings with their SCCmec types.We analyzed 71 clinical isolates, 39 S. aureus and 32 S. epidermidis, identified as erythromycin and methicillinresistant by automated systems, obtained between June 2004 and June 2009 from different hospitals in Rio de Janeiro city, Brazil. Among the isolates, 42% were from blood, 26% surgical sites, 9% cutaneous secretions, 7% tracheal secretions and 16% other sites. Twenty (62.5%)

The prevalence of genotypes that determine resistance to macrolides, lincosamides, and streptogramins B compared with spiramycin susceptibility among erythromycin-resistant Staphylococcus epidermidis

“…Only a few S. epidermidis exhibiting cMLS B phenotypes possessed ermA and/or ermB. Similar data have been previously reported ( Bouchami et al 2011 , Teodoro et al 2012 , Szczuka et al 2016 ). Moreover, the presence of other erm genes (e.g., ermF) has been rarely detected in Staphylococcus spp ( Roberts 2004) .…”

Vascular access infection by Staphylococcus aureus from removed dialysis accesses

“…The SCC mec type II and III isolates were multidrug resistant—predominantly to clindamycin, erythromycin, oxacillin, and penicillin, as well as highly resistant to fusidic acid and SXT. In addition, most of the HACO‐MRSA‐associated SCC mec type IV and V isolates remained susceptible to SXT; however, high resistance to clindamycin and erythromycin was still noticed in SCC mec types IV and V. In further antibiotic resistance gene characterization, our observations are in line with the findings of Teodoro, Mattos, Cavalcante, Pereira, and Santos (), in which the erm (A) gene was predominant in MRSA isolates and was correlated with SCC mec type III. In addition, they also found a relationship between erm (C) and SCC mec type IV.…”

Effects of Chlorophyll-Derived Efflux Pump Inhibitor Pheophorbideaand Pyropheophorbideaon Growth and Macrolide Antibiotic Resistance of Indicator and Anaerobic Swine Manure Bacteria

“…Msr(A) and Mef(A) are well known to confer erythromycin resistance in strains of S. aureus [27,95,96,101,102]. The plasmidborne Msr(A) transporter, even though mainly responsible for erythromycin efflux in S. aureus [103], is not present in the strain used in our study, S. aureus ATCC 29213 [104]. Mef(A) is closely related to Mef(B), the erythromycin efflux pump in E. coli P475.10.99.C3 [67], and as pyp decreased the final MIC endpoint for induced cultures of this strain (Figures 3(b) and 3(d)), it can be concluded that Mef(A) is an additional candidate for inhibition by pyp in S. aureus.…”