Successful development of air-dried microplates (HP-Plates) for susceptibility testing against Helicobacter pylori isolates.
We have successfully developed and evaluated a new susceptibility testing procedure against Helicobacter pylori strains using air-dried microplates "HP-Plates" containing eight serially-diluted anti-H. pylori agents. HP-Plate wells were reconstituted by the inoculation of 100 microliters of H. pylori cell suspensions. After incubation at 37 C for 48 hr under humidified microaerophilic conditions, HP-Plates were read visually with a circular mirror. We investigated the within-day reproducibility tests of HP-Plates using the six quality control (QC) strains we proposed. Of the 20 testings, determining the minimum inhibitory concentrations (MICs) of all the QC strains fell within +/- 1 log2 dilution ranges. When 200 clinical isolates were tested with HP-Plates and compared with the results obtained with the modified broth macrodilution method of NCCLS, more than 90% of the MICs also fell within +/- 1 log2 dilution ranges. We concluded that the HP-Plate susceptibility test method is a practical and easily applicable alternative of susceptibility testing for clinical microbiology laboratories in determining the MICs of H. pylori isolates.
Kawakami
Y
Y
Department of Medical Technology, School of Allied Medical Sciences, Shinshu University, Nagano, Japan. yk23724@gipac.shinshu-u.ac.jp
Akahane
T
T
Gotoh
A
A
Okimura
Y
Y
Oana
K
K
Katsuyama
T
T
D004352:Drug Resistance, Microbial; D004381:Duodenal Ulcer / Q000382:microbiology; D005756:Gastritis / Q000382:microbiology; D016481:Helicobacter Infections / Q000382:microbiology*; D016480:Helicobacter pylori / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000295:instrumentation*; D015203:Reproducibility of Results; D013276:Stomach Ulcer / Q000382:microbiology