title: A Microfluidic Channel Method for Rapid Drug-Susceptibility Testing of Pseudomonas aeruginosa.
abstract: The recent global increase in the prevalence of antibiotic-resistant bacteria and lack of development of new therapeutic agents emphasize the importance of selecting appropriate antimicrobials for the treatment of infections. However, to date, the development of completely accelerated drug susceptibility testing methods has not been achieved despite the availability of a rapid identification method. We proposed an innovative rapid method for drug susceptibility testing for Pseudomonas aeruginosa that provides results within 3 h. The drug susceptibility testing microfluidic (DSTM) device was prepared using soft lithography. It consisted of five sets of four microfluidic channels sharing one inlet slot, and the four channels are gathered in a small area, permitting simultaneous microscopic observation. Antimicrobials were pre-introduced into each channel and dried before use. Bacterial suspensions in cation-adjusted Mueller-Hinton broth were introduced from the inlet slot and incubated for 3 h. Susceptibilities were microscopically evaluated on the basis of differences in cell numbers and shapes between drug-treated and control cells, using dedicated software. The results of 101 clinically isolated strains of P. aeruginosa obtained using the DSTM method strongly correlated with results obtained using the ordinary microbroth dilution method. Ciprofloxacin, meropenem, ceftazidime, and piperacillin caused elongation in susceptible cells, while meropenem also induced spheroplast and bulge formation. Morphological observation could alternatively be used to determine the susceptibility of P. aeruginosa to these drugs, although amikacin had little effect on cell shape. The rapid determination of bacterial drug susceptibility using the DSTM method could also be applicable to other pathogenic species, and it could easily be introduced into clinical laboratories without the need for expensive instrumentation.
authors.affiliation: Institute of Scientific and Industrial Research, Osaka University, Osaka, Japan.
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Matsumoto
authors.affiliation: Institute of Scientific and Industrial Research, Osaka University, Osaka, Japan.
authors.forename: Shouichi
authors.initials: S
authors.lastname: Sakakihara
authors.affiliation: Institute of Scientific and Industrial Research, Osaka University, Osaka, Japan.
authors.forename: Andrey
authors.initials: A
authors.lastname: Grushnikov
authors.affiliation: Institute of Scientific and Industrial Research, Osaka University, Osaka, Japan.
authors.forename: Kazuma
authors.initials: K
authors.lastname: Kikuchi
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, University of Tokyo, Tokyo, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Noji
authors.affiliation: Institute of Scientific and Industrial Research, Osaka University, Osaka, Japan.
authors.forename: Akihito
authors.initials: A
authors.lastname: Yamaguchi
authors.affiliation: Okazaki Institute for Integrative Bioscience and Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki, Japan.|The Graduate University for Advanced Studies (SOKENDAI), Kanagawa, Japan.
authors.forename: Ryota
authors.initials: R
authors.lastname: Iino
authors.affiliation: Institute of Scientific and Industrial Research, Osaka University, Osaka, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Yagi
authors.affiliation: Institute of Scientific and Industrial Research, Osaka University, Osaka, Japan.
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Nishino
mesh_terms: D000583:Amikacin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002442:Ceftazidime / Q000494:pharmacology; D002939:Ciprofloxacin / Q000494:pharmacology; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000187:drug effects; D056656:Lab-On-A-Chip Devices; D000077731:Meropenem; D008826:Microbial Sensitivity Tests / Q000379:methods; D010878:Piperacillin / Q000494:pharmacology; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000254:growth & development; D013845:Thienamycins / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D013845:Thienamycins; D002939:Ciprofloxacin; D000583:Amikacin; D002442:Ceftazidime; D000077731:Meropenem; D010878:Piperacillin