title: Molecular detection of genes responsible for macrolide resistance among Streptococcus pneumoniae isolated in North Lebanon.
abstract: In recent years, the increased use of macrolides was linked with the emergence of resistance Streptococcus pneumoniae worldwide. The main aim of this study was to determine the prevalence of S. pneumoniae resistant to macrolides and to identify the macrolide resistance genotypes among clinical isolates collected in North Lebanon. Disk diffusion susceptibility method was performed for 132 strains of S. pneumoniae isolated over a period of 5 years in North Lebanon. Polymerase Chain Reaction followed by pyrosequencing was carried out for confirmation of phenotypic diagnosis. The macrolide resistance genotypes were also identified by using PCR amplification of genes implicated in this resistance: erm(A), erm(B), erm(C), msr(A), lin(A) and mef(A/E). Macrolide resistance was found in 34.1% of S. pneumoniae isolates. We observed that the cMLSBphenotype (31/45, 68.9%) was the most common in these pneumococci and erm(B) was the most common resistance gene (32/45, 71.1%). This study shows that macrolide resistance in S. pneumoniae in North Lebanon is mainly related to target site modification with predominance of cMLSb phenotype but is also mediated by efflux pumps. lin(A) gene was reported for the first time in one S. pneumoniae strain in combination with erm(B) and mef(A/E) genes.
authors.affiliation: Laboratoire Microbiologie Santé et Environnement (LMSE), Ecole Doctorale des Sciences et de Technologie, Faculté de Santé Publique, Université Libanaise, Tripoli, Lebanon.
authors.forename: Salam
authors.initials: S
authors.lastname: El Ashkar
authors.affiliation: Laboratoire Microbiologie Santé et Environnement (LMSE), Ecole Doctorale des Sciences et de Technologie, Faculté de Santé Publique, Université Libanaise, Tripoli, Lebanon.
authors.forename: Marwan
authors.initials: M
authors.lastname: Osman
authors.affiliation: Laboratoire Microbiologie Santé et Environnement (LMSE), Ecole Doctorale des Sciences et de Technologie, Faculté de Santé Publique, Université Libanaise, Tripoli, Lebanon.
authors.forename: Rayane
authors.initials: R
authors.lastname: Rafei
authors.affiliation: Laboratoire Microbiologie Santé et Environnement (LMSE), Ecole Doctorale des Sciences et de Technologie, Faculté de Santé Publique, Université Libanaise, Tripoli, Lebanon.
authors.forename: Hassan
authors.initials: H
authors.lastname: Mallat
authors.affiliation: Clinical Laboratory, Nini Hospital, Tripoli, Lebanon.
authors.forename: Marcel
authors.initials: M
authors.lastname: Achkar
authors.affiliation: Laboratoire Microbiologie Santé et Environnement (LMSE), Ecole Doctorale des Sciences et de Technologie, Faculté de Santé Publique, Université Libanaise, Tripoli, Lebanon.
authors.forename: Fouad
authors.initials: F
authors.lastname: Dabboussi
authors.affiliation: Laboratoire Microbiologie Santé et Environnement (LMSE), Ecole Doctorale des Sciences et de Technologie, Faculté de Santé Publique, Université Libanaise, Tripoli, Lebanon. Electronic address: mhamze@monzerhamze.com.
authors.forename: Monzer
authors.initials: M
authors.lastname: Hamze
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D052978:Disk Diffusion Antimicrobial Tests; D024881:Drug Resistance, Bacterial; D005798:Genes, Bacterial; D005838:Genotype; D006801:Humans; D007861:Lebanon / Q000453:epidemiology; D018942:Macrolides / Q000494:pharmacology*; D011008:Pneumococcal Infections / Q000453:epidemiology / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D015995:Prevalence; D013296:Streptococcus pneumoniae / Q000235:genetics* / Q000302:isolation & purification*
chemical_list: D000900:Anti-Bacterial Agents; D018942:Macrolides
keywords: Lebanon; Macrolide; Streptococcus pneumoniae; erm(B); lin(A); mef(A/E)