Glycopeptide intermediate Staphylococcus aureus and prevalence of the luk-PV gene in clinical isolates, in Northern Lebanon.
OBJECTIVE
The aim of our study was to confirm the identification of 113 meticillin-resistant Staphylococcus aureus (MRSA) strains by pyrosequencing, to determine the susceptibility of these clinical isolates to various classes of antibiotics, to determine the minimum inhibitory concentration (MIC) to glycopeptides, and to detect mecA and luk-PV genes.


METHODS
The Staphylococcus species was identified by pyrosequencing of the variable region (V3) of the 16SrRNA. The susceptibility of these 113 strains of MRSA to antibiotics was determined by the disk diffusion method on Mueller-Hinton agar. The MIC of glycopeptides was determined by using the dilution method on solid media. mecA gene and luk-PV gene were detected by PCR.


RESULTS
The disk diffusion method proved full susceptibility to vancomycin, teicoplanin, and linezolid; whereas MIC (dilution method) indicated that 5/113 strains were resistant to teicoplanin, giving a probability of having heterogeneous glycopeptide intermediate S. aureus (hGISA) strains. The mecA gene was detected in all MRSA strains ruling out the probability of having new variants of this gene in the tested strains. The luk-PV gene was detected in 28 out of 113 MRSA strains (24.8%).


CONCLUSIONS
The originality of this study was the detection of hGISA strains knowing that they were susceptible to glycopeptides according to the diffusion method. Thus it is necessary to check the level of susceptibility of MRSA clinical isolates to glycopeptides for immunodeficient patients, by determining the MIC.
Health and Environment Microbiology Laboratory, Azm Center for Research in Biotechnology and its Applications, Doctoral School of Sciences and Technology, Lebanese University, Mitein street, Tripoli, Lebanon.
M-D
MD
El Ayoubi
Health and Environment Microbiology Laboratory, Azm Center for Research in Biotechnology and its Applications, Doctoral School of Sciences and Technology, Lebanese University, Mitein street, Tripoli, Lebanon; Faculty of Public Health, Lebanese University, Tripoli, Lebanon. Electronic address: mhamze@monzerhamze.com.
M
M
Hamze
Health and Environment Microbiology Laboratory, Azm Center for Research in Biotechnology and its Applications, Doctoral School of Sciences and Technology, Lebanese University, Mitein street, Tripoli, Lebanon; Faculty of Public Health, Lebanese University, Tripoli, Lebanon.
H
H
Mallat
Clinical Laboratory, Nini Hospital, Tripoli, Lebanon.
M
M
Achkar
Health and Environment Microbiology Laboratory, Azm Center for Research in Biotechnology and its Applications, Doctoral School of Sciences and Technology, Lebanese University, Mitein street, Tripoli, Lebanon; Faculty of Public Health, Lebanese University, Tripoli, Lebanon.
F
F
Dabboussi
D001426:Bacterial Proteins / Q000235:genetics; D001427:Bacterial Toxins / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D052978:Disk Diffusion Antimicrobial Tests; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D005098:Exotoxins / Q000235:genetics*; D005798:Genes, Bacterial; D006801:Humans; D007861:Lebanon / Q000453:epidemiology; D007956:Leukocidins / Q000235:genetics*; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects / Q000235:genetics* / Q000472:pathogenicity; D008826:Microbial Sensitivity Tests; D046915:Penicillin-Binding Proteins; D015995:Prevalence; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D021521:Ribotyping; D017422:Sequence Analysis, DNA; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D017334:Teicoplanin / Q000494:pharmacology; D014640:Vancomycin / Q000494:pharmacology; D014774:Virulence / Q000235:genetics
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D005098:Exotoxins; D007956:Leukocidins; C078284:Panton-Valentine leukocidin; D046915:Penicillin-Binding Proteins; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; C487789:mecA protein, Staphylococcus aureus; D017334:Teicoplanin; D014640:Vancomycin
Leucocidine de Panton-Valentine; MRSA; Panton-Valentine leukocidin; SARM; Staphylococcus aureus; hGISA