Molecular Characterization of Staphylococcus aureus Isolates Resistant to Antibiotics Obtained
from Asymptomatic Carriers from Health Staff and Patients in a Hospital in Colombia
Monica Chavez1*, Alfonsina Martinez2 and Paola A Caro-Hernandez2
1 Faculty of Health, Universidad Santiago de Cali, Pampalinda Campus, Colombia
2 Faculty of Health Sciences, Universidad Libre, Cali Section, Colombia
*Corresponding Author: Monica Chavez, Faculty of Health, Universidad Santiago de Cali, Pampalinda Campus, Colombia.
January 16, 2018; Published: April 12, 2018
Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) is among the bacteria that are currently a motive for global alarm.
The aim of this study was to characterize antibiotic-resistant S. aureus isolates obtained from personal and patients in a hospital in
Materials and Methods: The study selected 381 S. aureus strains, 138 from patients with invasive infection and 243 obtained from
the health staff. An antibiogram was performed, along with detection of mecA, pvl and hgl genes, SCCmec, agr and spa typing and
analysis through Restriction Fragment Length Polymorphism (RFLP). Association among the variables was determined through the
chi squared test by using the SPSS statistical package v 22.0.
Results:Seven antibodies were determined among the S. aureus isolates. The anti-biotype 1 was the most prevalent (19.9%) and
found mainly in the health staff. The pvl and hlg genes were detected in 11.8% and 9.7%, respectively. The SCCmec I and III were
detected mainly in the health staff (62.5% and 97.2%, respectively), SCCmec II in blood (37.5%) and SCCmec type IV in deep wounds
(43.1%). The agr I was the most frequent, especially in deep wounds (45.1%). An RFLP was common in MSSA and MRSA. The spa VI
was the most frequent (53.7%), mainly in the health staff.
Conclusion: Presence of S. aureus was demonstrated and especially the MRSA colonized the health staff working in the hospital. The
highest number of MRSA was found in invasive infections with prevalence of CA-MRSA, which evidences that the most pathogenic
strains and with greater dissemination power are those being selected.
Keywords: Staphylococcus aureus Resistant to Methicillin; Typification; Health Staff; Invasive Infections
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