Methicillin-resistant Staphylococcus aureus Nasal Carriage Among Patients Admitted at Shaqra General Hospital in Saudi Arabia.

Background And Objective: Methicillin-resistant Staphylococcus aureus (MRSA) have been causing increasing problems in hospitals and nursing homes worldwide. Limited number of studies in Saudi Arabia has attempted to investigate infection and risk factors associated with nosocomial acquired MRSA. The present study was undertaken to determine the occurrence, prevalence, antibiotic susceptibility pattern and genetic characteristics of MRSA among admitted cases at Shaqra General Hospital (Saudi Arabia).

Methodology: This study was conducted from October, 2014 to March, 2015. Nasal swabs were taken from 220 patients (105 males and 115 females) admitted at Shaqra General Hospital. The isolates were identified as S. aureus based on morphology, Gram stain, catalase test, coagulase test and mannitol salt agar fermentation. Antibiotic susceptibility testing of MRSA was performed with standard disk diffusion method. All methicillin-resistant isolates were examined for the existence of the mecA gene by PCR technique.

Results: Of the 220 patients, 90 (40.91%) were found to be nasal carriers of S. aureus. Among these 90 S. aureus isolates, 48 (21.82%) were MRSA. A statistically significant difference was only found for antibiotics usage between those with and without MRSA colonization. Antibiotic susceptibility pattern of isolated MRSA showed high susceptibility to vancomycin, linezolid, rifampicin, teicoplanin, complete resistance to penicillin, ampicillin, oxacillin and cefoxitin and intermediate resistance to amikacin, ciprofloxacin, teicoplanin, tetracycline and vancomycin.

Conclusion: A high prevalence of multidrug-resistant MRSA nasal carriage was found. The identification of MRSA carriers is a step towards establishing a control policy for MRSA and helps to identify measures needed to reduce colonization pressure.