The Prevalence and Antimicrobial Susceptibility Profile of Methicillin-Resistant Staphylococcus Aureus Isolates from Clinical Specimens in a Tertiary Hospital; South East Nigeria

Pathogenic microorganisms resistant to commonly used antibiotics are of worldwide concern. Methicillin-resistant Staphylococcus aureus (MRSA) has been reported worldwide and causes both hospital and community-associated infections in humans. Sixty-five (65) Staphylococcus aureus isolates from clinical samples were screened for methicillin resistance in order to evaluate the prevalence of methicillin-resistant strains at Ebonyi State University Teaching Hospital; Abakaliki and to determine the antimicrobial susceptibility profile of MRSA strains. Susceptibility testing of the isolates to oxacillin and to some other conventional antimicrobial sensitivity discs commonly used in the study area was done using Kirby-Bauer disc diffusion technique. Of the 65 Staphylococcus aureus isolates screened; 15 (23) were susceptible to methicillin while 50 (77) were resistant to methicillin. The Methicillin-resistant isolates showed 100resistance to ciprofloxacin; ceftriaxone; nitrofurantoin and erythromycin. The percentage resistance recorded for other antibiotics were ofloxacin (88); ampicillin (76); gentamicin (72); while the lowest resistance; (40) was recorded for vancomycin. It was noted that vancomycin is still the antibiotic of choice for the treatment of MRSA infections. It was concluded that the prevalence of MRSA is high in the study area; and this should necessitate caution in the prescription of antibiotics without proper indication

Species Distribution and Antibiotic Resistance in Coagulase-negative Staphylococci Colonizing the Gastrointestinal Tract of Children in Ile-Ife; Nigeria

Purpose: The antimicrobial susceptibility of 149 coagulase-negative staphylococci (CoNS) isolates from faecal samples of children in Ile-Ife; Nigeria; was evaluated in order to determine their contribution to antimicrobial resistance in the community. Methods: The isolates were identified to the species level by conventional methods; and their susceptibility to 20 antibiotics was tested by disk diffusion and to vancomycin by agar dilution. Results: The species distribution was as follows: Staphylococcus epidermidis 45 (30.2); S. haemolyticus; 26 (17.5); S. capitis; 24 (16.1); S. xylosus; 11 (7.4); S. saprophyticus; 8 (5.4); S. warneri; 8 (5.4); S. hominis; 6 (4.0); S. schleiferi; 5 (3.3); S. lugdunensis; 3 (2.0) and S. capitis sub ureolyticus; 3 (2.0) and isolates from other CoNS species 10 (6.7). Resistance to the Beta-lactam antibiotics was in excess of 50of the isolates tested whilst there was significant incidence of resistance to cotrimoxazole; chloramphenicol; tetracycline; erythromycin; fusidic acid and norfloxacin. The highest percentage of oxacillin resistance was found among S. haemolyticus (46.2) while the lowest was in S. capitis (8.3). Reduced susceptibility (MIC = 4mg/L) to vancomycin was shown by both oxacillin-resistant and susceptible CoNS species. Conclusion: The gastrointestinal tracts of children could serve as a reservoir for antibiotic-resistant CoNS; some of which had reduced susceptibility to vancomycin

Species Distribution and Antibiotic Resistance in Coagulase-negative Staphylococci Colonizing the Gastrointestinal Tract of Children in Ile-Ife; Nigeria

Purpose: The antimicrobial susceptibility of 149 coagulase-negative staphylococci (CoNS) isolates from faecal samples of children in Ile-Ife; Nigeria; was evaluated in order to determine their contribution to antimicrobial resistance in the community. Methods: The isolates were identified to the species level by conventional methods; and their susceptibility to 20 antibiotics was tested by disk diffusion and to vancomycin by agar dilution. Results: The species distribution was as follows: Staphylococcus epidermidis 45 (30.2); S. haemolyticus; 26 (17.5); S. capitis; 24 (16.1); S. xylosus; 11 (7.4); S. saprophyticus; 8 (5.4); S. warneri; 8 (5.4); S. hominis; 6 (4.0); S. schleiferi; 5 (3.3); S. lugdunensis; 3 (2.0) and S. capitis sub ureolyticus; 3 (2.0) and isolates from other CoNS species 10 (6.7). Resistance to the - lactam antibiotics was in excess of 50of the isolates tested whilst there was significant incidence of resistance to cotrimoxazole; chloramphenicol; tetracycline; erythromycin; fusidic acid and norfloxacin. The highest percentage of oxacillin resistance was found among S. haemolyticus (46.2) while the lowest was in S. capitis (8.3). Reduced susceptibility (MIC 4mg/L) to vancomycin was shown by both oxacillin-resistant and susceptible CoNS species. Conclusion: The gastrointestinal tracts of children could serve as a reservoir for antibiotic-resistant CoNS; some of which had reduced susceptibility to vancomycin