In vitro Activity of Ceftaroline Against an International Collection of Kingella kingae Isolates Recovered From Carriers and Invasive Infections.

Background: Improvements in blood culture techniques and molecular-based diagnostics have led to increased recognition of Kingella kingae as an invasive human pathogen causing bacteremia, septic arthritis, osteomyelitis and endocarditis in young children. Serious disease and potentially life-threatening complications of infection due to K. kingae necessitate timely identification and appropriate antimicrobial therapy.

Delayed resistance selection for doripenem when passaging Pseudomonas aeruginosa isolates with doripenem plus an aminoglycoside.

Doripenem (formerly S-4661), a parenteral carbapenem, was tested in combination with an aminoglycoside (gentamicin) to determine the resistance selection of these codrugs during subinhibitory passaging using 6 Pseudomonas aeruginosa isolates. The organisms were selected based on doripenem and gentamicin MIC values to include isolates with MIC values near the susceptible breakpoints of both compounds and 1 strain highly resistant to gentamicin. Baseline MIC values were established for doripenem (2-8 microg/mL) and gentamicin (4 to >256 microg/mL) using reference broth microdilution methods, and passaging was carried out over 7 consecutive days.

Activities of doripenem (S-4661) against drug-resistant clinical pathogens.

Doripenem (formerly S-4661), a new 1-beta-methyl carbapenem, was challenged with a worldwide collection of 394 drug-refractory isolates. For endemic extended-spectrum beta-lactamase- and stably derepressed AmpC-producing enteric bacilli, the doripenem MICs at which 90% of the isolates were inhibited (MIC90s) were 0.03 to 0.

Doripenem (S-4661), a novel carbapenem: comparative activity against contemporary pathogens including bactericidal action and preliminary in vitro methods evaluations.

Objectives: To investigate the potency of doripenem, a broad-spectrum carbapenem characterized by a wider spectrum of activity combining antimicrobial and bactericidal features of imipenem and meropenem.

Methods: This parenteral compound was studied against recent clinical isolates (2001-2002) from a worldwide organism collection. A total of 902 strains were susceptibility tested by reference methods against doripenem and six to 28 comparators including ertapenem, imipenem and meropenem.

Contemporary in vitro synergy rates for aztreonam combined with newer fluoroquinolones and beta-lactams tested against gram-negative bacilli.

Aztreonam has been commonly used in various combinations to enhance antimicrobial spectrum of co-drugs and produce potential synergistic activity. Although well studied in vitro over 10 years ago, aztreonam combination testing has been poorly documented with newer or commonly used agents against contemporary isolates. All MIC tests (alone or in combination) used in this experiment were reference broth microdilution methods in checkerboard tray designs.