Abstract
Nosocomial infections due to multidrug resistant Staphylococcus aureus are an important health problem worldwide. Antimicrobial resistance prolongs the duration of hospitalization, thereby increasing the cost of patient care. For a long time, methicillin was considered as drug of choice for treatment of penicillin-resistant staphylococcal infections. Emergence of methicillin resistance reduced the available options for treatment of nosocomial and community acquired S. aureus. Normally, such strains are only sensitive to glycopeptides such as vancomycin and teicoplanin. Recent reports show that methicillin resistant S. aureus (MRSA) have become multiply resistant to other drugs such as fluoroquinolones, trimethoprim-sulfamethoxazole (SXT), clindamycin or erythromicin and there are reports of vancomycin resistant strains from different parts of the world. The aim of this study was to determine the susceptibility patterns of Staphylococcus isolates from humans. Drug susceptibility testing of isolates was determined using the disk diffusion method. A total of 110 S. aureus (SA) and 23 coagulase negative staphylococcus (CoNS) isolates from human sources were studied. Both SA and CoNS isolates were completely sensitive to vancomycin. On one hand, there was a comparable high resistance for both SA and CoNS to penicillin G, augmentin and tetracycline. On the other hand, there was significantly high resistance to erythromycin (69.6%), SXT (69.6%), oxacillin (82.6%), ciprofloxacin (52.2%) and clindamycin (39.1%) among CoNS when compared with SA isolates (erythromycin 38.2%, SXT 38.2, oxacillin (33.6%), ciprofloxacin (26.4%), clindamycin 18.2%) with p values 0.0090, 0.0099, 0.0001, 0.0239 and 0.0483, respectively. These high levels of resistance, calls for continuous surveillance studies to monitor for S. aureus infections in the community and hospital settings and the emergence of vancomycin resistant isolates. Key words: Methicillin resistant, Staphylococcus aureus, methicillin resistant Staphylococcus aureus (MRSA), antibiotic susceptibility, vancomycin, coagulase negative staphylococci.
Highlights
Staphylococcus aureus is a common cause of both community and hospital-acquired infections
The aim of this study was to determine the proportion of methicillinresistant S. aureus (MRSA) and investigate the antimicrobial susceptibility patterns of both coagulase positive and coagulase negative staphylococcal strains isolated from humans in Nairobi, to commonly used antibiotics and vancomycin
It is well recognized that vancomycin resistance is more prevalent in the United States than in Europe, it has not been explained why avoparcin usage fails to correlate with the different epidemiologies of resistance between the two continents; avoparcin was never approved for use in animals in the United States, in contrast to its broad use as a growthpromoting agent in Europe (Donnelly et al, 1996; Leclercq and Courvalin, 1997)
Summary
Staphylococcus aureus is a common cause of both community and hospital-acquired infections. The introduction of penicillin in the 1930s had a dramatic impact on the treatment of S. aureus infections. Methicillinresistant S. aureus (MRSA) strains rapidly emerged and became a major clinical problem within hospitals during the 1960s in Europe and the 1970s in the United States and elsewhere (Enright et al, 2000). MRSA was first reported in England in 1961, shortly after its introduction (Mulvey et al, 2001). Worldwide reports show that MRSA strains are resistant to most other classes of antimicrobial agents and are susceptible only to glycopeptides and a few new investigational drugs (Enright et al, 2000; Lee, 2003)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
