Combination effect of Erythromycin And Clindamycin On Staphylococcus Aureus , Isolated From Different Clinical Sources

Abstract

The study included isolation and diagnosis 10 isolates o from Staphylococcus aureus out of 211 samples collected from different infectious sources for the period from 10/09/2015 to 1/1/2016. The highest rate for the isolation these bacteria from wounds swabs was 9.5%, and vaginal swabs were 8%. Burns swabs 6.9%, pharynx was 4 %, and ear swabs was 1.6. The results of investigating the virulence factors for Staphylococcus bacteria isolates showed that all isolates have ability to produce Hemolysin by 100 % , it, but for the Staphylokinase by 80% have the ability to produce it, while for the production efflux pumps was 9 isolates by 90%. The investigation of the sensitivity of isolates against 12 antibiotic , showed that all isolates were resistant to the Penicillin G by 100% , while the isolates were resistante to Erythromycin by 60% , The resistant for Clindamycin was 50%, while the resistance of for Vancomycin was 40%, and the resistance for Gentamicin was 40%. The Minimum Inhibition Concentration MIC for 2 of antibiotics i .e. Erythromycin, Clindamycin antibiotic have ranged between (256-1024), (64-1024), µg / mL, respectively Results of mixing Erythromycin with Clindamycin showed a significant reduction in the ranges of MIC of antibiotics after the mixing process than it is in the case of the use of each antibiotic alone. The results also showed that the mixing ratio (1: 3) is the best among the other ratios where all the isolates under study showed synergistic effect on nine isolates out of 10 isolates by 90 %. The results of mixing Clindamycin with Erythromycin showed a significant reduction in the ranges of MIC of antibiotics after the mixing process and the results showed that the mixing ratio (1: 2 and 1: 3) is the best among other proportions as it showed that all the isolates under study have synergistic effect on 7 and 9 isolates by 70% and 90% . Results of plasmid profile of S. aureus isolates showed one band