Abstract:
This study was carried out in Khartoum State, during
the period
from December 2003 to October 2005, to study the prevalence of
methicillin resistant Staphylococcus aureus (MRSA) among patients
attending different hospitals and evaluate the in vitro activity of
penicillin,
amoxicillin,
cephalexin,
cloxacillin,
methicillin
and
vancomycin by using National Committee on Clinical of Laboratory
Standard (NCCLS) modified Kirby-Bauer Disc Diffusion Technique
against S. aureus strains isolated from patients attending different
hospitals. This study was done on 248 samples collected from infected
wound and urinary tract.
The specimens were cultured on blood agar, and McConkey’s agar
for primary isolation. Identification was done by Gram’s stain, catalase
test, co-agulase test, DNAse test and mannitol fermentation.
A total of 163 clinical isolates of S. aureus were recorded,
15 (9.2%) isolates from these were MRSA.
The results obtained from this study showed that the MRSA remain
a versatile and dangerous pathogen in human with frequency of 9.2%
between patients infected by S. aureus and also showed that the most
effective antimicrobial against S. aureus was vancomycin (99%), because
it had the lowest resistance rate. The sensitivity rate of cephalexin,
penicillin, amoxicillin, cloxacillin, and methicillin, were 147/163 (93%)
23/163
(14%),
17/163(10%),
55/163
(34%)
and
147/163(90%)
respectively.
Vancomycin was also evaluated for its effectiveness on
Staphylococcus aureus resistant to cephalixin (90%).