Vancomycin resistance among Staphylococcus aureus isolates in a rural setting, Egypt.

Introduction: With the increased occurrence of methicillin resistant S. aureus (MRSA), the consumption of vancomycin, the drug of choice, has also increased. As a consequence, strains of S. aureus resistant to vancomycin have started to emerge. This study aimed to evaluate the level of vancomycin resistance among clinical and nasal S. aureus isolates in a rural town in Egypt.

Methods: This cross-sectional study was held in the general hospital at the rural town of Kafr Eldawar in Egypt, during the period from January 2013 to January 2014. S. aureus isolates were collected from clinical samples and from nasal swabs.

Results: Two hundred S. aureus isolates were collected, 80 (40%) from clinical samples and 120 (60%) from nasal carriage samples. Vancomycin resistant S. aureus (VRSA) was only detected in clinical samples, all collected from the outpatient clinic. Eleven VRSA isolates (13.8% of total S. aureus clinical isolates) and one strain of vancomycin-intermediate S. aureus (from nasal carriage) were detected. VRSA isolates were most resistant to ciprofloxacin (90.9%) and erythromycin (81.8%). Five isolates were resistant to all tested antibiotics: ciprofloxacin, clindamycin, erythromycin, linezolid, oxacillin, penicillin and trimethoprim-sulfamethoxazole. MRSA was found to constitute 43.8% of clinical S. aureus isolates. The MRSA colonization rate among community individuals was 43.6%, 42.9% among healthcare workers and 51.4% among patients.

Conclusion: The prevalence of VRSA was high in clinical samples suggesting that there is a high level of VRSA strains in Egypt that goes undetected since most laboratories only use disk diffusion for detection of vancomycin resistance.