Toxin genes and antimicrobial resistance in MRSA isolated from intensive care unit

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Özgüler K., Aksu M. B., Hasdemir M. U., Söyledir G.

6th Congress of the Microbiologists of Macedonia, Ohrid, Makedonya, 30 Mayıs - 02 Haziran 2018

  • Yayın Türü: Bildiri / Özet Bildiri
  • Basıldığı Şehir: Ohrid
  • Basıldığı Ülke: Makedonya
  • Marmara Üniversitesi Adresli: Evet

Özet

INTRODUCTION

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the leading causes of hospital-acquired infections worldwide. Antibiotic resistance and toxins contributing to bacterial virulence have a significant role in pathogenesis of MRSA infections, which cause high morbidity and mortality in ICU patients.

OBJECTIVES

In this study, we aimed to determine the toxigenic properties anc antibiotic susceptibility profile of MRSA isolated from ICU patients during 2016-2017.

MATERIAL, METHODS

A total of 36 MRSA isolated from ICU patients were included. Identification was performed by MALDI-TOF MS (Vitek MS, bioMerieux, France) and antibiotic susceptibility was determined by using an automated system (VITEK 2 Compact, bioMerieux). We used PCR to detect the genes encoding for Panton-Valentine leukocidin (PVL, lukS / F), toxic shock toxin-1 (tst) and enterotoxins (sea, seb, sec, sed, see).

RESULTS

Study isolates obtained from following clinical samples; DTA (n = 21), blood (n = 9), wound swab (n = 4) and other samples (n = 2). A total of 30 isolates (30/36; 83.3%) were positive for one or more toxin genes. The distribution of the toxin genes is shown below Table. The staphylococcal enterotoxin D and E genes (sed and see) could not be detected in any isolate. All isolates were sensitive to linezolid, vancomycin, tigecycline and daptomycin. Resistance rates against other tested antibiotics ranged from 13.9% to 52.8%.

CONCLUSION

In our study, toxin production rate in MRSA isolates from ICU patients was found to be as high as 83.3%. Among the toxin-positive isolates, Panton-Valentine leukocidin carriers have a significant share (75%). Antibiotic resistance rates are especially high in isolates carrying Staphylococcal enterotoxin A (sea). In addition to toxin production capability and antibiotic susceptibility profiles, identification of the clonal relationship of these isolates and monitoring of spread in the hospital environment would be beneficial in terms of infection control.