Faiqa Arshad*, Iffat Javed*, Tajammal Mustafa**, Sohaila Mushtaq*,
Saeed Anwer,*** Farida Rafique**
*Pathology Department, PGMI, Lahore, **Community Medicine Department, FJMC, Lahore,
*** Pathology Department, CMH, Lahore,
Objectives: To compare the in vitro activity of quinopristin/dalfopristin, linezolid and vancomycin by determining their minimum inhibitory concentrations (MICs) for methicillin-resistant Staphylococcus aureus (MRSA) isolated from various clinical samples received from LGH, Lahore.
Study Design : Comparative Study
Place and Duration of Study: Pathology Department, Post Graduate Medical Institute, Lahore from February 2013 to October 2013.
Methodology: The MIC of quinopristin/dalfopristin, linezolid and vancomycin for 50 MRSA strains were determined by using E-test strips (AB Biodisk, Biomeurix) and results were interpreted according to clinical and laboratory standards institute (CLSI) guidelines.
Results: All the isolates showed 100% susceptibility to linezolid and quinopristin/dalfopristin and currently no resistant strain was found for these drugs. Quinopristin/dalfopristin showed lowest MIC values than Linezolid and vancomycin.
Conclusion: The study provided the in vitro information in establishing the role of linezolid and quinopristin/dalfopristin as an alternative to vancomycin for the treatment of serious MRSA infections. It also gives information regarding linezolid and quinopristin/dalfopristin as the best therapeutic option for the treatment of hVISA, VISA and VRSA.
Key Words: Methicillin Resistant Staphylococcus aureus, Minimum Inhibitory concentration, Epsilometer Test, heteroresistant Vancomycin Intermediate Staphylococcus aureus, Vancomycin Intermediate Staphylococcus aureus, Vancomycin Resistant Staphylococcus aureus, Clinical Laboratory and Standard Institute.