Evaluation of tigecycline activity on wound isolates of methicillinresistant Staphylococcus aureus from hospital and communityacquired infections in Cross River State, Nigeria
Ubong A. Udoh, Ernest A. Ochang, Emmanuel E. Effa, Kenneth I. Onyedibe, Usang E. Usang, Onyebuchi E. Osakwe, Joseph E. Asuquo.
Background/Objective: Tigecycline belongs to the glycylcycline class of antibiotics with in-vitroactivity against most gram-positive bacteria, including multidrug-resistant pathogens. Methicillin-resistant Staphylococcus aureus (MRSA) is one of such pathogen, which has been associated with community and hospital-acquired infections. Tigecycline is considered to be a newer treatment option for emerging multidrug-resistant bacteria. This study aims to determine the in-vitro activity of tigecycline against community and hospital-acquired MRSA isolated from infected traumatic wounds in Cross River State.
Material and Methods: A total of 60 MRSA were isolated from wound samples, 30 each from the community and hospital settings. These were tested for tigecycline susceptibility by the E-test method. Detection of methicillin resistance was performed using cefoxitin (30µg) disk. All strains were identified according to standard bacteriological methods.
Results: Of the 60 isolates, 55 (91.7%) were sensitive to tigecycline with MIC50 and MIC90 values of 0.25 and 0.5μg/ml, respectively. Twenty-seven (90.0%) of the 30 community-acquired isolates were susceptible to tigecycline, while 28 (93.3%) of the 30 hospital-acquired isolates were susceptible.
Conclusions: Tigecycline showed excellent in-vitro activity against MRSA wound isolates and, therefore may be a drug of choice for empirical therapy of skin and soft tissue infections in areas where MRSA is prevalent.
Key words: MRSA, Tigecycline, MIC, Antimicrobial susceptibility, E-Test