Comparative studies of the bactericidal, morphological and post- antibiotic effects of arbekacin and vancomycin against methicillin- resistant Staphylococcus aureus

Abstract

Arbekacin, an aminoglycoside antibiotic, has antibacterial activity against both Gram-positive and Gram-negative bacteria and is stable in the presence of aminoglycoside-inactivating enzymes produced by methicillin-resistant Staphylococcus aureus (MRSA). In this report, the antibacterial activity of arbekacin was compared with that of vancomycin, a glycopeptide antibiotic that also has potent antibacterial activity against MRSA. Arbekacin showed concentration-dependent bactericidal activity against MRSA strain 1936 (0.5-2 x MIC), but vancomycin showed only slight bactericidal activity, even at high concentrations of 19 x MIC. Arbekacin showed a longer post-antibiotic effect (2.3-3.8 h) than vancomycin (0-1.3 h) against MRSA strain 1936. Arbekacin induced marked morphological changes at 0.5 x MIC and the changes remained for 2 h after removal of the agent. When exposed to 0.5 x MIC of vancomycin, no notable morphological change was observed in the treated cells. Since arbekacin has broad-spectrum activity, these findings suggest that it may be a useful agent against MRSA infection, especially for polymicrobial MRSA infection with Gram-negative bacilli, such as Pseudomonas aeruginosa.

Efficacies of Vancomycin, Arbekacin, and GentamicinAlone or in Combination against Methicillin-Resistant Staphylococcus aureus in an In Vitro InfectiveEndocarditisModel

“…However, most of the studies done on the effect of arbekacin were performed on the basis of an in vitro method (4,17,30,33). An in vitro infection model offers the benefits of effectiveness in evaluation of the efficacy of an antibiotic (since the half-life, dose, and interval could be regulated to fit human pharmacokinetics), no difference compared with animal models, and the fact that the study environment could be regulated (8,9,19).…”

In Vitro Activities of Daptomycin, Arbekacin, Vancomycin, and Gentamicin Alone and/or in Combination against Glycopeptide Intermediate-Resistant Staphylococcus aureus in an Infection Model

“…Arbekacin is a broad-spectrum aminoglycoside, used in Japan for a number of years, that is active against MRSA organisms that have a variety of aminoglycoside-inactivating enzymes (19). The enzyme AAC-6/APH-2Љ, which can inactivate aminoglycosides, has been reported to have a low modification rate, and the ANT (4Ј)-1 aminoglycoside-modifying enzyme has no effect on arbekacin (12).…”

Clinical Characteristics of Invasive Methicillin-Resistant Staphylococcus aureus at General Hospital in the Central Region of Japan from July 2014 to June 2015

“…Arbekacin is not inactivated by aminoglycoside-inactivating enzymes [14]. Arbekacin shows the most potent antibacterial effect against clinically isolated MRSA strains among the aminoglycosides such as gentamicin, tobramycin, and amikacin [15], and the antibacterial effect of arbekacin is equivalent to that of vancomycin [15]. When MRSA is treated either with arbekacin or vancomycin with the same concentration, the post antibiotic effect of vancomycin was shorter compared with arbekacin [16].…”