meropenem and clinafloxacin

Acinetobacter baumannii is an opportunistic pathogen associated with numerous nosocomial infections. In recent years it has shown extraordinary ease in developing resistance to most antimicrobial agents, which is a serious problem as it makes these infections difficult to treat. We determined the in vitro activity of eight quinolones, five betalactam agents and colistin in 160 clinical isolates of A. baumannii. In general, we observed a high rate of resistance to the quinolones (90%), excluding clinafloxacin (25%), and to ampicillin-sulbactam (61.25%) and imipenem (50%). Colistin is the agent with least resistance (13.125%), although its toxicity limits its therapeutic use. Clinafloxacin may be a good option to treat A. baumannii infections, especially in cases of therapeutic failure with other antimicrobial agents.

Topics: Acinetobacter; Acinetobacter Infections; Ampicillin; Anti-Infective Agents; Aza Compounds; Cefepime; Cephalosporins; Ciprofloxacin; Colistin; Fluoroquinolones; Gatifloxacin; Humans; Imipenem; Meropenem; Microbial Sensitivity Tests; Moxifloxacin; Nalidixic Acid; Naphthyridines; Norfloxacin; Ofloxacin; Opportunistic Infections; Quinolines; Sulbactam; Thienamycins

The most appropriate therapy for meningitis caused by Streptococcus pneumoniae strains resistant to the extended-spectrum cephalosporins is unknown. We evaluated ceftriaxone, vancomycin, and rifampin alone and in different combinations and meropenem, cefpirome, and clinafloxacin alone in the rabbit meningitis model. Meningitis was induced in rabbits by intracisternal inoculation of one of two pneumococcal strains isolated from infants with meningitis (ceftriaxone MICs, 4 and 1 microgram/ml, respectively). Two doses, 5 h apart, of each antibiotic were given intravenously (except that ceftriaxone was given as one dose). Cerebrospinal fluid bacterial concentrations were measured at 0, 5, 10, and 24 h after therapy was started. Clinafloxacin was the most active single agent against both strains. Against the more resistant strain, ceftriaxone or meropenem alone was ineffective. The combination of vancomycin and ceftriaxone was synergistic, suggesting that this combination might be effective for initial empiric therapy of pneumococcal meningitis until results of susceptibility studies are available.

Topics: Animals; Anti-Bacterial Agents; Anti-Infective Agents; Cefpirome; Ceftriaxone; Cephalosporins; Disease Models, Animal; Drug Resistance, Microbial; Drug Synergism; Drug Therapy, Combination; Fluoroquinolones; Male; Meningitis, Pneumococcal; Meropenem; Microbial Sensitivity Tests; Penicillin Resistance; Quinolones; Rabbits; Rifampin; Thienamycins; Vancomycin