Trends of β-lactam antibiotic susceptibility in blood-borne methicillin-resistant Staphylococcus aureus (MRSA) and their linkage to the staphylococcal cassette chromosome mec (SCCmec) type

Hospitalizations related to Methicillin-resistant Staphylococcus aureus (MRSA) are frequent, increasing mortality and health costs. In this way, this study aimed to compare the genotypic and phenotypic characteristics of MRSA isolates that colonize and infect patients seen at two hospitals in the city of Niterói—Rio de Janeiro, Brazil. A total of 147 samples collected between March 2013 and December 2015 were phenotyped and genotyped to identify the protein A (SPA) gene, the mec staphylococcal chromosomal cassette (SCCmec), mecA, Panton-Valentine Leucocidin (PVL), icaC, icaR, ACME, and hla virulence genes. The strength of biofilm formation has also been exploited. The prevalence of SCCmec type IV (77.1%) was observed in the colonization group; however, in the invasive infection group, SCCmec type II was prevalent (62.9%). The Multilocus Sequence Typing (MLST), ST5/ST30, and ST5/ST239 analyses were the most frequent clones in colonization, and invasive infection isolates, respectively. Among the isolates selected to assess the ability to form a biofilm, 51.06% were classified as strong biofilm builders. Surprisingly, we observed that isolates other than the Brazilian Epidemic Clone (BEC) have appeared in Brazilian hospitals. The virulence profile has changed among these isolates since the ACME type I and II genes were also identified in this collection.

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The First Report of a Methicillin-Resistant Staphylococcus aureus Isolate Harboring Type IV SCCmec in Thailand

Pathogens ◽

10.3390/pathogens10040430 ◽

2021 ◽

Vol 10 (4) ◽

pp. 430

Author(s):

Wichai Santimaleeworagun ◽

Praewdow Preechachuawong ◽

Wandee Samret ◽

Tossawan Jitwasinkul

Keyword(s):

Staphylococcus Aureus ◽

Resistance Genes ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Sccmec Type ◽

Clinical Strain ◽

Spa Typing ◽

Methicillin Resistant ◽

Type Iv ◽

Antimicrobial Resistance Genes

Methicillin-resistant Staphylococcus aureus (MRSA) is mostly found in Thailand in the hospital as a nosocomial pathogen. This study aimed to report the genetic characterization of a clinical community-acquired MRSA (CA-MRSA) isolate collected from hospitalized patients in Thailand. Among 26 MRSA isolates, S. aureus no. S17 preliminarily displayed the presence of a staphylococcal cassette chromosome mec (SCCmec) type IV pattern. The bacterial genomic DNA was subjected to whole-genome sequencing. Panton–Valentine leukocidin (PVL) production, virulence toxins, and antibiotic resistance genes were identified, and multi-locus sequence typing (MLST) and spa typing were performed. The strain was matched by sequence to MLST type 2885 and spa type t13880. This strain carried type IV SCCmec with no PVL production. Five acquired antimicrobial resistance genes, namely blaZ, mecA, Inu(A), tet(K), and dfrG conferring resistance to β-lactams, lincosamides, tetracycline, and trimethoprim, were identified. The detected toxins were exfoliative toxin A, gamma-hemolysin, leukocidin D, and leukocidin E. Moreover, there were differences in seven regions in CR-MRSA no. S17 compared to CA-MRSA type 300. In summary, we have reported the ST2885-SCCmec IV CA-MRSA clinical strain in Thailand for the first time, highlighting the problem of methicillin resistance in community settings and the consideration in choosing appropriate antibiotic therapy.

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Detection of Methicillin Resistant Staphylococcus aureus in Dairy Products and Anterior Nares of Dairy Workers

Tribhuvan University Journal of Microbiology ◽

10.3126/tujm.v6i0.26585 ◽

2019 ◽

Vol 6 ◽

pp. 59-62

Author(s):

Ranjana K.C. ◽

Ganga Timilsina ◽

Anjana Singh ◽

Supriya Sharma

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Susceptibility ◽

Dairy Products ◽

Methicillin Resistant Staphylococcus Aureus ◽

Dairy Product ◽

Control Measures ◽

Diffusion Method ◽

Mannitol Salt Agar ◽

Methicillin Resistant ◽

Dairy Workers

Objectives: To isolate methicillin resistant Staphylococcus aureus (MRSA) from anterior nares of dairy workers and dairy products and assess the antibiotic susceptibility pattern of the isolates. Methods: Swab samples collected from anterior nares of dairy workers and dairy product (butter) were inoculated into mannitol salt agar and incubated at 37ºC for 24 hours. Identification was done based on colony characteristics, Gram's staining, catalase, oxidase and coagulase test. Antibiotic susceptibility testing was done by modified Kirby Bauer disc diffusion method. MRSA was confirmed by using cefoxitin disc. Results: A total of 109 S. aureus (98 from dairy workers and 11 from butter samples) were isolated. Out of them 32 MRSA were isolated from dairy workers and 4 from butter samples. The association between age group and MRSA was found insignificant (p = 0.115). The association of MRSA between male and female workers was found significant (>0.05). About 86% of the MRSA isolates were susceptible to Gentamicin (86.11%) followed by Ciprofloxacin (77.78%). Conclusion: Detection of MRSA among dairy workers and dairy products warrants proper handling and adequate control measures to prevent transmission of MRSA from dairy industry.

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Antibiotic susceptibility pattern of staphylococcus aureus and methicillin-resistant staphylococcus aureus in a tertiary care hospital

Journal of Pathology of Nepal ◽

10.3126/jpn.v4i7.10297 ◽

2014 ◽

Vol 4 (7) ◽

pp. 548-551 ◽

Cited By ~ 3

Author(s):

CP Bhatt ◽

BMS Karki ◽

B Baral ◽

S Gautam ◽

A Shah ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Susceptibility ◽

Methicillin Resistant Staphylococcus Aureus ◽

Penicillin G ◽

Care Hospital ◽

Age Group ◽

Susceptibility Pattern ◽

Antibiotic Susceptibility Pattern ◽

Methicillin Resistant ◽

Drug Of Choice

Background: Methicillin resistant Staphylococcus aureushas emerged as one of the most important nosocomial pathogens. It invokes a tremendous financial burden and enhanced morbidity and mortality due to difficult to treat systemic infections.Aim of this study was to determine antibiotic susceptibility pattern of Staphylococcus aureus and Methicillin resistant Staphylococcus aureus. Materials and Methods: Different clinical specimens were collected and processed for routine culture and antibiotic sensitivity test by standard microbiology techniques. Results: Out of 1173 samples received for microbiological examination, 100 were found to be S. aureus with 19% cases were Methicillin resistant Staphylococcus aureus (MRSA). Fourteen MRSA were found from inpatient and 5 were from outpatient. MRSA was found higher in female than male and maximum number (31.5%) was found in age group 0-10 years. Staphylococcus aureus was 100% sensitive to Vancomycin followed by Amikacin (90%), Gentamycin (83%), and tetracycline (81%). On urine isolates Nitrofurantoin(91.6%) was drug of choice. All the isolates were resistant to Penicillin G. In case of Methicillin resistant Staphylococcus aureus showed 100% sensitive to Vancomycin followed by Amikacin (84.2%), Tetracycline (63.1%), Ciprofloxacin (42%) and Gentamycin (36.8%). Among urine isolates Nitrofutantoin showed 87.5% sensitive followed by Norfloxacin (75%). Conclusion: Methicillin resistant Staphylococcus aureus was found 19% of Staphylococcus aureus isolates. It was most common in females, hospitalized patients and young age group. Vancomycin seems to be drug of choice followed by Amikacin. It would be helpful to formulating and monitoring the antibiotic policy and ensure proper empiric treatment. DOI: http://dx.doi.org/10.3126/jpn.v4i7.10297 Journal of Pathology of Nepal (2014) Vol. 4, 548-551

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