meropenem and telavancin

Combination therapy is recommended for infections with carbapenemase-producing Klebsiella pneumoniae. However, limited data exist on which antibiotic combinations are the most effective. The aim of this study was to find effective antibiotic combinations against metallo-beta-lactamase-producing K. pneumoniae (MBL-KP). Two VIM- and two NDM-producing K. pneumoniae strains, all susceptible to colistin, were exposed to antibiotics at clinically relevant static concentrations during 24-h time-kill experiments. Double- and triple-antibiotic combinations of aztreonam, ciprofloxacin, colistin, daptomycin, fosfomycin, meropenem, rifampin, telavancin, tigecycline, and vancomycin were used. Synergy was defined as a ≥2 log10 decrease in CFU/ml between the combination and its most active drug after 24 h, and bactericidal effect was defined as a ≥3 log10 decrease in CFU/ml after 24 h compared with the starting inoculum. Synergistic or bactericidal activity was demonstrated for aztreonam, fosfomycin, meropenem, and rifampin in double-antibiotic combinations with colistin and also for aztreonam, fosfomycin, and rifampin in triple-antibiotic combinations with meropenem and colistin. Overall, the combination of rifampin-meropenem-colistin was the most effective regimen, demonstrating synergistic and bactericidal effects against all four strains. Meropenem-colistin, meropenem-fosfomycin, and tigecycline-colistin combinations were not bactericidal against the strains used. The findings of this and other studies indicate that there is great potential of antibiotic combinations against carbapenemase-producing K. pneumoniae. However, our results deviate to some extent from those of previous studies, which might be because most studies to date have included KPC-producing rather than MBL-producing strains. More studies addressing MBL-KP are needed.

Topics: Aminoglycosides; Anti-Bacterial Agents; Aztreonam; beta-Lactamases; Ciprofloxacin; Colistin; Daptomycin; Drug Resistance, Multiple, Bacterial; Drug Synergism; Fosfomycin; In Vitro Techniques; Klebsiella pneumoniae; Lipoglycopeptides; Meropenem; Microbial Sensitivity Tests; Minocycline; Rifampin; Thienamycins; Tigecycline; Vancomycin

To report a case of multidrug-resistant osteomyelitis successfully treated with telavancin, rifampin, and meropenem.. An 18-year-old male with spina bifida was treated primarily in the outpatient setting over the course of 133 days with multiple antimicrobials for a recurrent right calcaneal wound and osteomyelitis infection. Initial cultures were positive for methicillin-resistant Staphylococcus aureus and coagulase-negative Staphylococcus, which were treated with intravenous vancomycin 1 g every 12 hours, increased after 13 days to 1.5 g every 12 hours with addition of rifampin 300 mg twice daily, both of which were discontinued on day 22 due to leukopenia (white blood cell count 3.0 × 10(3)/μL) and neutropenia (absolute neutrophil count 0.2 × 10(3)/μL). Daptomycin 8 mg/kg/day was then initiated with rifampin 300 mg twice daily; treatment was discontinued after 49 days due to an elevated creatine kinase level of 1831 U/L (baseline 86). Intravenous meropenem 1 g every 8 hours was again initiated on day 83 following additional identification of quinolone-resistant Pseudomonas aeruginosa from the soft tissue of the right foot. Intravenous vancomycin 1 g every 12 hours was also restarted at this time for persistent coagulase-negative Staphylococcus and oral rifampin 300 mg twice daily was again added. Adverse events again required the discontinuation of vancomycin on day 91. The eventual drug therapy regimen consisted of telavancin 750 mg/day for 42 days, meropenem for 50 days, and oral rifampin for 50 days. At the end of treatment, the patient's right heel wound had almost completely closed. He was without recurrence or treatment-related adverse events at follow-up 1 year later.. Antimicrobial selection for osteomyelitis infections presents a challenge to the clinician due to patient intolerance, increasing antimicrobial resistance, and variable antimicrobial penetration at the site of infection. To our knowledge, this is the first case report of the successful use of a regimen including telavancin for the treatment of a recurrent, coagulase-negative Staphylococcus osteomyelitis infection.. In this complex case involving a polymicrobial infection of the right calcaneal bone and surrounding soft tissue, eventual drug therapy including telavancin, meropenem, and rifampin resulted in a successful clinical response.

Topics: Adolescent; Aminoglycosides; Anti-Bacterial Agents; Coinfection; Drug Therapy, Combination; Humans; Lipoglycopeptides; Male; Meropenem; Osteomyelitis; Rifampin; Staphylococcal Infections; Thienamycins; Treatment Outcome

Synergy time-kill studies against 40 methicillin-resistant Staphylococcus aureus (MRSA) strains of differing resistance phenotypes were conducted. Subinhibitory concentrations of telavancin were combined with sub-MIC concentrations of other antimicrobial agents that might be used in combination with telavancin to provide Gram-negative coverage. The highest incidence of synergy was found after 24 h with gentamicin (90% of strains), followed by ceftriaxone (88%), rifampin and meropenem (each 65%), cefepime (45%), and ciprofloxacin (38%) for combinations tested at or below the intermediate breakpoint for each agent.

Topics: Aminoglycosides; Anti-Bacterial Agents; Cefepime; Ceftriaxone; Cephalosporins; Ciprofloxacin; Drug Synergism; Gentamicins; Lipoglycopeptides; Meropenem; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Oxacillin; Rifampin; Thienamycins; Time Factors