title: 'Break-point Checkerboard Plate' for screening of appropriate antibiotic combinations against multidrug-resistant Pseudomonas aeruginosa.
abstract: Increase of multiple drug resistant Pseudomonas aeruginosa (MDRP) is becoming a serious problem in the clinical setting. Although the checkerboard method to determine FIC index and synergistic effects of antibiotic combinations is useful, it is not well adapted to a routine test, mainly because of its time-consuming and labor-intensive nature. Here we report 'Break-point Checkerboard Plate', in which breakpoint concentrations, such as 'S' (sensitive) and 'I' (intermediate), were combined in a microtiter plate with 8 antibiotics, including carbapenem, aminoglycoside and fluoroquinolone. The results obtained from 12 strains of MDRP demonstrated a strong synergistic effect of some antibiotic combinations at clinically relevant concentrations. Our data suggest a usefulness of 'Break-point Checkerboard Plate' to screen appropriate antibiotic combinations against drug resistant organisms, including MDRP.
authors.affiliation: Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Ohtaku, Tokyo, Japan. kazu@med.toho-u.ac.jp
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Tateda
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Ishii
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Keizo
authors.initials: K
authors.lastname: Yamaguchi
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004338:Drug Combinations; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects*; D008826:Microbial Sensitivity Tests / Q000379:methods*; D011550:Pseudomonas aeruginosa / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents; D004338:Drug Combinations