Dataset Information

A Low Prevalence of Inducible Macrolide, Lincosamide, and Streptogramin B Resistance Phenotype among Methicillin-Susceptible Staphylococcus aureus Isolated from Malaysian Patients and Healthy Individuals.

ABSTRACT: BACKGROUND:Antibiotic resistance among Staphylococcus aureus is of great concern worldwide. This resistance is further complicated by the ability of S. aureus to confer cross-resistance to other antibiotics due to the presence of resistance genes, such as erythromycin resistance methylase (erm) genes, which render the bacterium resistant to macrolide-lincosamide-streptogramin B (MLSB) antibiotics. Resistance to these antibiotics can lead to therapeutic failure, resulting in significant morbidity and mortality in patients with S. aureus infections. OBJECTIVES:This study was performed to examine the distribution of MLSB-resistant strains of methicillin-susceptible S. aureus (MSSA), which were obtained from hospitalized patients and normal healthy individuals (carriers) using phenotypic methods, such as the double-disk diffusion (D-test) and the genotypic method by polymerase chain reaction (PCR). METHODS:A total of 183 nonduplicative MSSA isolates obtained from hospitalized patients (133) and carriers (50) in our previous studies were randomly selected for the D-test. The guidelines of the Clinical and Laboratory Standards Institute (CLSI) were used for the interpretation of the results of this test. The detection of ermA, ermB, ermC and msrA genes by PCR was performed for isolates that had positive D-test results and that were resistant to erythromycin. RESULTS:Of the 183 MSSA isolates, 97.2% and 98.4% were highly susceptible to erythromycin and clindamycin, respectively. MSLB resistance was detected in four isolates (2.2%). Of the 133 MSSA isolated from hospitalized patients, only 3.0% (4/133) and 2.3% (3/133) exhibited resistance to erythromycin and clindamycin, respectively. With regard to the MLSB resistance phenotypes, only 1.6% and 0.6% exhibited inducible MLSB (iMLSB) and MS phenotypes, respectively. The ermC gene was detected in all three iMLSB phenotypes, and the msrA gene was detected in the MS phenotype. Surprisingly, all MSSA isolates (100%) from carriers exhibited extremely high susceptibility to both antibiotics. CONCLUSIONS:The prevalence rates of iMLSB MSSA isolates vary according to geographical locations and the local antibiotic policy. The low prevalence rate of iMLSB MSSA isolates could probably be related to the judicious use of antibiotics for treating S. aureus infections in our studied population. Nonetheless, continuous antibiotic surveillance is still necessary to control any emergence of resistance isolates so that targeted therapy and effective control can be implemented accordingly.

SUBMITTER: Mesbah Elkammoshi A

PROVIDER: S-EPMC5136447 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A Low Prevalence of Inducible Macrolide, Lincosamide, and Streptogramin B Resistance Phenotype among Methicillin-Susceptible <i>Staphylococcus aureus</i> Isolated from Malaysian Patients and Healthy Individuals.

Mesbah Elkammoshi Asma A Ghasemzadeh-Moghaddam Hamed H Amin Nordin Syafinaz S Mohd Taib Niazlin N Kumar Subbiah Suresh S Neela Vasanthakumari V Awang Hamat Rukman R

Jundishapur journal of microbiology 20160910 10

<h4>Background</h4>Antibiotic resistance among <i>Staphylococcus aureus</i> is of great concern worldwide. This resistance is further complicated by the ability of <i>S. aureus</i> to confer cross-resistance to other antibiotics due to the presence of resistance genes, such as erythromycin resistance methylase (<i>erm</i>) genes, which render the bacterium resistant to macrolide-lincosamide-streptogramin B (MLSB) antibiotics. Resistance to these antibiotics can lead to therapeutic failure, resul ...[more]

PMID: 27942364

Similar Datasets

Project description:ObjectivesTo describe and analyse erythromycin resistance trends in blood isolates of Staphylococcus aureus (EARS-Net Spain, 2004-2020) and the association of these trends with the consumption of macrolide, lincosamide, and streptogramin B (MLSB) antibiotics. To assess molecular changes that could be involved in erythromycin resistance trends by whole genome analysis of representative isolates.Materials and methodsWe collected antibiotic susceptibility data for all first-blood S. aureus isolates in patients from 47 Spanish hospitals according to EARS-Net criteria. MLSB antibiotic consumption was obtained from the Spanish Agency for Medicines and Medical Devices (2008-2020). We sequenced 137 representative isolates for core genome multilocus sequence typing, resistome and virulome analysis.ResultsFor the 36,612 invasive S. aureus isolates, methicillin resistance decreased from 26.4% in 2004 to 22.4% in 2020. Erythromycin resistance in methicillin-susceptible S. aureus (MSSA) increased from 13.6% in 2004 to 28.9% in 2020 (p < 0.001); however, it decreased from 68.7 to 61.8% (p < 0.0001) in methicillin-resistant S. aureus (MRSA). Total consumption of MLSB antibiotics increased from 2.72 defined daily doses per 1,000 inhabitants per day (DID) in 2014 to 3.24 DID in 2016. By WGS, the macrolide resistance genes detected were erm (59.8%), msrA (46%), and mphC (45.2%). The erm genes were more prevalent in MSSA (44/57, 77.2%) than in MRSA (38/80, 47.5%). Most of the erm genes identified in MSSA after 2013 differed from the predominant ermC gene (17/22, 77.3%), largely because ermT was significantly associated with MSSA after 2013 (11/29, 37.9%). All 13 ermT isolates in this study, except one, belonged to ST398 and came from 10 hospitals and six Spanish provinces.ConclusionThe significant increase in erythromycin resistance in blood MSSA correlated with the consumption of the MLSB antibiotics in Spain. These preliminary data seem support the hypothesis that the human ST398 MSSA clade with ermT-mediated resistance to erythromycin may be involved in this trend.

Project description:BackgroundSolithromycin, the fourth generation of ketolides, has been demonstrated potent antibacterial effect against commonly-isolated gram-positive strains. However, Staphylococcus aureus (S. aureus) strains with a higher solithromycin MIC have already been emerged, the mechanism of which is unknown.MethodsAntimicrobial susceptibility test was performed on 266 strains of S. aureus. The antibiotic resistance phenotype of erm-positive strain was determined by D-zone test. Spontaneous mutation frequency analysis was performed to compare the risk levels for solithromycin resistance among different strains. Efflux pumps and mutational analysis of ribosomal fragments as well as erm(B) gene domains were detected. Quantitative reverse transcription polymerase chain reaction was conducted to compare the transcriptional expression of the erm gene between the constitutive macrolide-lincosamide-streptogramin B (cMLSB)- and inducible MLSB (iMLSB)-phenotypes.ResultsIn the erm-positive S. aureus strains, the minimum inhibitory concentration (MIC)50/90 of solithromycin (2/> 16 mg/L) was significantly higher than that in the erm-negative strains (0.125/0.25 mg/L). Of note, the MIC50 value of the strains with iMLSB (0.25 mg/L) was significantly lower than that of the strains with cMLSB (4 mg/L). A comparison among strains demonstrated that the median mutational frequency in isolates with cMLSB (> 1.2 × 10- 4) was approximately > 57-fold and > 3333-fold higher than that in iMLSB strains (2.1 × 10- 6) and in erythromycin-sensitive strains (3.6 × 10- 8), respectively. The differential antibiotic in vitro activity against strains between cMLSB and iMLSB could not be explained by efflux pump carriers or genetic mutations in the test genes. The expression of the erm genes in strains with cMLSB did not differ from that in strains with iMLSB.ConclusionsThe reduced susceptibility to solithromycin by S. aureus was associated with the cMLSB resistance phenotype mediated by erm.

Dataset Information

A Low Prevalence of Inducible Macrolide, Lincosamide, and Streptogramin B Resistance Phenotype among Methicillin-Susceptible Staphylococcus aureus Isolated from Malaysian Patients and Healthy Individuals.

Publications

A Low Prevalence of Inducible Macrolide, Lincosamide, and Streptogramin B Resistance Phenotype among Methicillin-Susceptible <i>Staphylococcus aureus</i> Isolated from Malaysian Patients and Healthy Individuals.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets