Activities of ciprofloxacin, levofloxacin, ofloxacin and sparfloxacin against speciated coagulase-negative staphylococci sensitive and resistant to fluoroquinolones.
A total of 119 strains of coagulase-negative staphylococci isolated from clinical specimens were speciated and tested for sensitivity to methicillin and four fluoroquinolones (ciprofloxacin, sparfloxacin, levofloxacin and ofloxacin). Resistance to fluoroquinolones was significantly more common in Staphylococcus haemolyticus (43%) than in Staphylococcus epidermidis (11%). Methicillin-resistant strains of S. haemolyticus were more often resistant to ciprofloxacin than were methicillin-resistant strains of S. epidermidis (P < 0.05). Sparfloxacin was the most active against fluoroquinolone-sensitive strains, and levofloxacin was twice as active as ofloxacin. There was cross-resistance between the four fluoroquinolones. Levofloxacin was the most active against resistant strains, but MICs obtained for all the compounds seemed to be outside the clinically useful range for the treatment of systemic infections.
Hamilton-Miller
J M
JM
Department of Medical Microbiology, Royal Free Hospital School of Medicine, Pond St., London NW3 2QG, UK.
Shah
S
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