Characterization of ST80 Panton-Valentine leukocidin-positive community-acquired methicillin-resistant Staphylococcus aureus clone in Tunisia (original) (raw)
Related papers
Microbiologia Medica, 2019
Resistance to methicillin in methicillin resistant Staphylococcus aureus (MRSA) is dependent on mecA gene located on staphylococcal cassette chromosome (SCC). Both SCCmec type and Panton-Valentine leukocidin (PVL) affect S. aureus pathogenicity. Aim of this study was to investigate the prevalence of SCCmecA types and pvl genes among MRSA isolates from inpatients. During this cross-sectional study on 100 clinical isolates, following antibiotic susceptibility test, screening of mecA and pvl genes, as well as SCCmec typing, was done in a multiplex PCR technique. From the studied samples, 58 isolates were recognized as MRSA. The frequency of mecA and pvl was 58% and 4%, respectively. All of the MRSA were resistant to cefoxitin and had the highest sensitivity to chloramphenicol. The majority (77.5%) of MRSA was originated from wound samples. The SCCmec III was the most frequent type (22.4%) in these samples. The pvl positive isolates were from SCCmec IVb and V, thus meaning they are from...
MOLECULAR CHARACTERIZATION OF MRSA, 2017
Objective: The purpose of this study is to investigate the methicillin resistance gene, and some virulence factors in methicillin-resistant Staphylococcus aureus (MRSA) isolates by polymerase chain reaction (PCR). Methods: This study has included 12 MRSA isolates. All isolates were previously identified as S. aureus by a standard microbiological procedure, and a detection of methicillin resistance was realized by phenotypic methods. Following genomic DNA extraction, the presence of gyrA, mecA, lukPV, and tst genes was analyzed by duplex PCR. All retained S. aureus species have been found to contain gyrA gene. Results: Ten stains have been found to harbor mecA gene indicating it's responsibility for methicillin resistance in those strains. Among the 12 strains, six of which were found to be Panton-Valentine leukocidine positive while none of which has tst gene encoding the toxic shock syndrome toxin. Conclusion: The pathogenesis of MRSA infections is related to the expression of a wide variety of virulence factors.
Chemotherapy, 2021
Background: Emergence and prevalence of Methicillin-Resistant Staphylococcus aureus (MRSA) has become a major universal health concern, limiting therapeutic options. Methods: In the North side of Iran, during the years 2015 to 2017, a total number of 37 MRSA isolates, including 19 clinical isolates from hospitalized patients and 18 colonizing isolates from health care workers were identi ed from three hospitals, in Gorgan, North of Iran. Antimicrobial susceptibility test was performed using the disk diffusion method and E-test. The presence of virulence and antibiotic resistance determinants were evaluated by PCR. The genotypic characterization was further analyzed using multi-locus sequence, spa, SCCmec, and agr typing. Results: The frequency of MRSA among S. aureus isolates was 38.14% (37/97). The most frequent S. aureus resistant isolates were found to be obstinate against penicillin (98%) and gentamicin (82.5%). Additionally, the lowest resistance rates were found against daptomycin (0%), vancomycin (2.7%), and quinupristin-dalfopristin (5.4%). All MRSA isolates were susceptible to daptomycin with MIC 50 /MIC 90 of 0.25/0.5 µg/ml. One isolate belonging to the ST239-SCCmecIII/t037 clone (MIC≥16μg/ml) was resistant to vancomycin. All but one isolate that shares the ST22-SCCmec IV/t790 strain were positive for both tsst and pvl genes. The most predominant MRSA isolates (27%) were associated with the ST239-SCCmec III/t037 clone; and followed by ST239-SCCmec III/t924 (16.2%). Conclusions: In our study, circulating MRSA strains were genetically diverse with a high prevalence of the ST239-SCCmecIII/t037 clone. These ndings emphasize the need for future and continuous surveillance studies on MRSA to prevent the dissemination of multidrug resistance and existing MRSA clones in an effective manner. [2, 13]. The geographical differences in the genotypic characteristic of MRSA have been reported [2]. In Asia, there is signi cant divergence among countries and regions with respect to prevalence of MRSA; in fact, ST22-SCCmec IV/t790 and ST239-SCCmec III/t037 clones are predominant among patients in Iran [2, 14], and so is ST239-spa t037 and ST5-spa t002 in China [15]. On the other hand, in many regions in Asia [16, 17], sequence type 239 (ST239) is most prevalent, where, in UK, ST36 and ST30 are the most common types [18]. With this background, we are evaluating the molecular characteristics, antibiotic resistance patterns, and virulence genes pro les of MRSA isolates obtained from two kinds of study populations, namely hospitalized patients and health care workers (HCWs) in Gorgan, North of Iran. Methods Study Design and Sample Collection of S. aureus Isolates This cross-sectional study was conducted from January 2, 2016 to October 28, 2018 in three hospitals (total of 920-beds) in Gorgan, North of Iran. Written informed consent was obtained from all the patients or HCWs and the study protocol was approved by the Ethics Committee in Golestan University of Medical Sciences (No. 31078693122419), and was conducted in accordance with the Declaration of Helsinki. The demographic pro les of patients and HCWs were recorded. We identi ed S. aureus and MRSA in hospitalized patients and HCWs as well (Table 1). Only the rst sample of each patient was included in the study. In case of HCWs, samples were collected from both anterior nares. 302 unduplicated clinical samples (blood, urine, wound, sputum, and others) were obtained from in-patients, out of which S. aureus and MRSA were identi ed in 53 (17.5%), and 19 specimens (6.29%), respectively. Likewise, 351 unduplicated non-clinical samplings from the anterior nares of HCWs were carried out. All the samples were sent for bacterial culturing and identi cation, using Gram staining, and standard biochemical tests, such as catalase, tube coagulase, DNase test, and mannitol fermentation [19]. The identi cation process of all S. aureus isolates was con rmed by using genotypic methods for the presence of nucA, and femA genes [2, 20]. Data on department and period of hospitalization, clinical symptoms, antibiotic usages, and underlying conditions were recorded.
BMC Microbiology, 2012
BackgroundThe spread of MRSA strains at hospitals as well as in the community are of great concern worldwide. We characterized the MRSA clones isolated at Tunisian hospitals and in the community by comparing them to those isolated in other countries.ResultsWe characterized 69 MRSA strains isolated from two Tunisian university hospitals between the years 2004-2008. Twenty-two of 28 (79%) community-associated MRSA (CA-MRSA) strains and 21 of 41 (51%) healthcare-associated MRSA (HA-MRSA) strains were PVL-positive. The PVL-positive strains belonged to predicted founder group (FG) 80 in MLST and carried either type IVc SCCmec or nontypeable SCCmec that harbours the class B mec gene complex. In contrast, very diverse clones were identified in PVL-negative strains: three FGs (5, 15, and 22) for HA-MRSA strains and four FGs (5, 15, 45, and 80) for CA-MRSA strains; and these strains carried the SCCmec element of either type I, III, IVc or was nontypeable. The nucleotide sequencing of phi7401...
Chemotherapy
Objectives: Emergence and prevalence of methicillin-resistant Staphylococcus aureus (MRSA) have become a major universal health concern, limiting therapeutic options. Methods: A total number of 37 MRSA isolates, including 19 clinical isolates from hospitalized patients and 18 colonizing isolates from health care workers were identified from 3 hospitals, in Gorgan, North of Iran. Antimicrobial susceptibility test was performed using the disk diffusion method and E-test. The presence of virulence and antibiotic resistance determinants were evaluated by PCR. The genotypical characterization was further analyzed using multi-locus sequence, spa, staphylococcal cassette chromosome, mec (SCCmec), and agr typing. Results: The frequency of MRSA among S. aureus isolates was 38.14% (37/97). The most frequent S. aureus resistant isolates were found to be obstinate against penicillin (98%) and gentamicin (82.5%). Additionally, the lowest resistance rates were found against daptomycin (0%), vanco...
European journal of microbiology and immunology, 2013
Molecular characterization of methicillin-resistant Staphylococcus aureus (MRSA) isolates in three different Arab world countries (West Bank of Palestine, Jordan, and Iraq) was the aim of the study presented here. This is done on the basis of spa sequencing and staphylococcal cassette chromosome mec (SCCmec) typing. The majority (92%) of the spa-tested isolates belonged to spa type t932 and possessed the (SCCmec) type III. These data suggest that MRSA clone, which harbors the spa type t932 and (SCCmec) type III, had been transferred throughout the three studied countries.
European journal of microbiology & immunology, 2013
Molecular characterization of methicillin-resistant Staphylococcus aureus (MRSA) isolates in three different Arab world countries (West Bank of Palestine, Jordan, and Iraq) was the aim of the study presented here. This is done on the basis of spa sequencing and staphylococcal cassette chromosome mec (SCCmec) typing. The majority (92%) of the spa-tested isolates belonged to spa type t932 and possessed the (SCCmec) type III. These data suggest that MRSA clone, which harbors the spa type t932 and (SCCmec) type III, had been transferred throughout the three studied countries.
Archives of Pediatric Infectious Diseases, 2017
Background: Methicillin resistant Staphylococcus aureus (MRSA) are one of the most common and important pathogens, accounting for diverse nosocomial and community-acquired infections. The serious concern about these bacteria is the development of antibiotic resistance. Objectives: The present study was conducted to investigate the frequency of MRSA strains, their epidemiological and molecular relationships and antibiotic susceptibility patterns of isolated strains from university teaching hospitals of Tabriz, Northwestern Iran (during years 2014 and 2015). Methods: A total of 215 non-repetitive clinical isolates of S. aureus were identified using standard methods. The MRSA isolates were detected by the combination of phenotypic and genotypic methods. The presence of pvl gene and SCCmec types was determined by PCR and multiplex PCR, respectively. The MRSA isolates, in which the presence of mecA gene had been confirmed by PCR, were subjected to Rep-PCR analysis. Resistance to antibacterial agents was determined by disk diffusion, screening agar, and E-test methods. Results: All S. aureus isolates were positive for nuc gene and 87 (40.5%) of them revealed the presence of mecA gene, confirming them as MRSA. All isolates were found to be sensitive to linezolid and vancomycin. However, a reduced sensitivity of 3 MRSA isolates to vancomycin was observed (MIC = 6 µg/mL). SCCmec type III was the most prevalent (79.31%), followed by type IVd (13.80%) and type I (6.90%). The PVL occurrence was detected in 33 (15.35%) S. aureus isolates. The MRSA isolates could be divided to 2 main clusters, indicating the possible clonal relatedness of MRSA isolates. Conclusions: The MRSA isolates with SCCmec type III were the predominant MRSA strains in this area. The majority of MRSA isolates were MDR. Linezolid and vancomycin were found as suitable antibiotics for the treatment of MRSA. The results of typing methods indicated possible clonal relatedness among MRSA isolates. Therefore, routine infection control surveillance is necessary for the prevention of epidemic emergence.
Molecular characterization of methicillin-resistant Staphylococcus aureus isolated in Tunisia
Diagnostic Microbiology and Infectious Disease, 2006
We characterized 34 methicillin-resistant Staphylococcus aureus strains isolated in Paraguay in 2005. The strains belonged to two clones. The major clone (sequence type 5 [ST5] or ST221, spa type t149, staphylococcal cassette chromosome mec [SCCmec] type I) was similar to the Cordobes/Chilean clone spreading through South America, and the minor clone (ST239 or ST889, spa type t037, SCCmec type IIIA) was related to the Brazilian clone.