Response of Complicated Methicillin‐ResistantStaphylococcus aureusEndocarditis to the Addition of Trovafloxacin

Abstract

The newer fluoroquinolones have many properties such as safety, bioavailability, and tissue penetration that make them attractive in the therapy of complicated infections. Unfortunately, the rapid development of resistance by Staphylococcus aureus to ciprofloxacin has dampened interest in these agents for serious staphylococcal infections. A patient with right-sided methicillin-resistant Staphylococcus aureus (MRSA) endocarditis with a complicated clinical course received trovafloxacin in addition to vancomycin and rifampin. He was initially treated with vancomycin, gentamicin, and rifampin for serious MRSA infection, but because of complications, including septic central nervous system emboli, persistent fever, and leukocytosis, gentamicin was stopped and trovafloxacin begun. After this addition the patient improved and completely recovered. In vitro and animal model data show that many newer fluoroquinolones have excellent activity against S. aureus, including MRSA, and are also less likely to induce resistance. Animal models of endocarditis support their efficacy in serious staphylococcal infections.

Phenotypic profiles of nasal methicillin resistant Staphylococcus aureus from asymptomatic children of Iligan City

“…The lowered susceptibility of the isolates to the betalactam ampicillin conforms to the reports (Hizel et al, 1997;Eckart et al, 2000) on the emergence of the beta-lactam-specific resistant mutants of staphylococci, which may eventually to the total resistance of these bacterial strains to the antibiotic.…”

“…Table 1 shows the number of susceptible isolates to the three antibiotics. (Hizel et al, 1997;Eckart, Hospenthal, Fishbain, 2000) on the emergence of beta-lactam-specific resistant mutants of staphylococci, which may eventually result to resistance of these bacterial stains to the antibiotic.…”

Pharmacodynamic Evaluation of the Intracellular Activities of Antibiotics against Staphylococcus aureus in a Model of THP-1 Macrophages

“…The choice of a unique, well-characterized strain was actually essential for addressing the question of antibiotic intracellular activity per se and avoiding the blurring of the results because of other factors that can modulate the intracellular response to antibiotics, such as virulence and variations in the expression of resistance mechanisms. Given this caveat and pending further studies with clinical strains, the data presented in this paper may provide unambiguous pharmacological support to the use of new quinolones (7,17) or oritavancin (40), as an alternative to ␤-lactams (68), for the treatment of recurrent S. aureus infections, provided that sufficient extracellular concentration/MIC ratios are obtained for a sufficient period of time. These conditions may not be obtainable for more toxic drugs such as aminoglycosides or conventional glycopeptides and will not be met with bacteriostatic antibiotics.…”