Affiliation:
1. Department of Basic Medical Sciences, Faculty of Medicine, Hashemite University, Zarqa, Jordan
Abstract
Introduction:
Nasal carriers of Staphylococcus aureus are common and play an important
role in the transmission of infections. The aim of this study is a phenotypic and molecular investigation
of nasal methicillin- and vancomycin-resistant S. aureus in hospitalized patients.
Methods:
202 nasal swabs were collected from patients at Prince Hamzah Hospital, Jordan,
through 2016-2017. Swabs were processed according to standard microbiological procedures to
isolate Staphylococci. Antibiotic susceptibility testing was performed using disk diffusion, E-test,
microdilution and Vitek 2. Methicillin resistance was confirmed by testing for the mecA gene,
while vancomycin resistance was screened by testing for the vanA and vanB genes.
Results:
The mean age of participants was 50.17±18.18 years and 59.4% were females. Nasal
Staphylococci was isolated in 64/202 (31.7%), S. aureus was isolated from 33 samples (16.3%),
MRSA was isolated from 13 samples (6.4%) and constitutive Macrolide-lincosamidestreptogramin
B (MLSB) was isolated from 12 samples (5.9%). All MRSA isolates harbored the
mecA gene. All isolates were sensitive to vancomycin using E-test and the microdilution test and
were negative for the vanA and vanB genes. The highest resistance rate was observed for benzylpenicillin
(>90%), while the lowest resistance rate was for tobramycin (<5%) among all isolates.
Nasal Staphylococci, S. aureus and MRSA colonization significantly correlate with increased
number of family members and previous hospitalization (P<0.05), while nasal S. aureus
significantly correlates with a history of skin infection (P=0.003).
Conclusions:
Nasal colonization by mecA-mediated MRSA is common among hospitalized patients,
while vanA- and vanB-mediated vancomycin resistance was not detected in any nasal isolates.
Publisher
Bentham Science Publishers Ltd.
Subject
Microbiology (medical),Pharmacology,Molecular Medicine,General Medicine