| خلاصه مقاله | Hemodialysis is the most common method of alternative treatment in kidney patients. In these patients,
due to weak immune system and continuous use of venous catheter for dialysis, the possibility of
hospital infection is high. The most common cause of infection in these patients is Staphylococcus
aureus bacteria. Vancomycin is now identified as a last resort for the infection control. The aim of this
study is to investigate the prevalence of resistance to methicillin and vancomycin in Staphylococcus(S.)
aureus isolates collected from dialysis patients of Imam Reza Hospital in Tabriz, Iran
MATERIALS AND METHODS
Swab Samples were obtained from nasal, throat and catheter of 230 dialysis patient at Imam Reza
Hospital in Tabriz, Iran. the isolation of S. aureus bacteria was performed by conventional
microbiological methods. Antibiotic sensitivity patterns of isolates were determined by disk diffusion
method and E-test. The frequency of Van A, Van B and mecA genes was detected by PCR reaction.
RESULTS AND DISCUSSION
Among the 170 S. aureus isolates collected from hemodialysis patients in this investigation, the highest
resistance was observed to Ampicillin (79.41%), while the highest sensitivity was observed against
Rifampin (82.94%). For the detection of vancomycin resistant isolates, E- test was performed for 35
isolates that was found as vancomycin resistant isolates based on disk diffusion results. The results
showed that 37.14% of the samples were resistant, 14.28% were sensitive, and 20% showed
intermediate resistance to vancomycin. According to the PCR results, 29.41% of patients were positive
for mecA gene, 5.29% for the vanA gene, and 7.05% were positive for the vanB gene. All the isolates
carrying vanA and vanB were resistant to Ampicillin (7.05%), Cefoxitin (5.29%), Erythromycin
(4.70%), Methicillin (3.52%), and Oxacillin (3.52%). The number of female patients carrying the
vancomycin-resistant gene was higher than the number of men(p<0.05). Based on results, there is a
significant relationship between diabetes and high blood pressure prevalence and resistance to
methicillin and vancomycin.
Conclusion
Because of the increasing prevalence of resistance to methicillin and vancomycin, it is necessary to
propose an appropriate antibiotic pattern to halter resistant infections in patients with weak immune
system like hemodialysis patients. |