Abstract:
Emergence of Mecthicillin resistance Staphylococcus aureus is of public health
concern contributing to increase morbidity and mortality among infected patients
The present study is aimed to determine the prevalence and molecular detection of
MRSA, VISA and VRSA among patients in Khartoum state. The enrolled study
population (n=426) were patients who attended the main Khartoum Hospitals
(Military Hospital, Alrebat University Hospital, Khartoum Teaching Hospital and
Khartoum North Teaching Hospital) in Khartoum State, Sudan extending from April
2010 to May 2011.
The study subjects involved 211 males and 215 females with different age categories.
Enrolled subjects were suffering from wound infections (105), ear infections (121),
Urinary tract infections (UTI) (100), in addition to nasal discharge of medical staff
(100).
Clinical samples were cultured on blood agar and MacConkey agar. Cystine lysine
electrolyte deficiency (CLED) agar was also used for urine samples. Gram staining
and other biochemical tests were also performed for conventional identification. The
results confirmed the existence of Staph. aureus in 49/426 (11.5%) cases among
which MRSA were isolated from 34/49 (69.4%) when modified Kirbry-Bauer disk
diffusion method was applied. Ten out of these 34 MRSA were confirmed as VRSA
by culturing on BHI agar containing 6μg/ml vancomycin according to National
Control Culture Standard (NCCLS) criteria.
DNA was extracted from the 34 MRSA isolates (including the 10 VRSA) by phenol-
chloroform method. PCR was then performed to amplify of arcC, mecA, VanA and
VanB genes. Out of the 34 MRSA isolates DNA, 26 were mecA positive (76.5%)
while 8 (23.5%) were arcC positive. But, vanA and B genes where not amplified
In conclusion, genotype analysis confirmed the existence of MRSA among Sudanese
But the same procedure failed to prove the occurrence of VRSA a mediated resistance
indicating that among Sudanese isolates VRSA may be attributed to other factors.