Reassessment of the Broth Microdilution Method for Susceptibility Testing of Helicobacter pylori

Abstract

Background Helicobacter pylori infection is an infectious disease and thus the eradication treatment should be guided by susceptibility testing. This study aimed to assess the applicability of broth microdilution as a routine susceptibility testing method for H. pylori. Methods Susceptibility profiles of clarithromycin (CLR) and levofloxacin (LEV) resistance in 76 clinical H. pylori isolates were simultaneously assessed using agar dilution and broth microdilution methods. The correlation between the minimum inhibitory concentrations (MICs) obtained by the 2 methods was assessed by means of linear regression analysis. Results The correlation between the MICs determined by broth microdilution method and agar dilution method was good for both CLR (r = 0.966) and LEV (r = 0.959). The susceptibility agreement between the 2 methods was 100% for CLR and 96.1% for LEV. Using the broth microdilution method, the false resistance was found in 3.9% (3 of 76) strains for LEV susceptibility testing. No false susceptibility was found for either CLR or LEV, and no false resistance was found for susceptibility testing of CLR. Conclusions The broth microdilution method is suitable for routine susceptibility testing of clinical H. pylori isolates.

Rapid Non-Invasive Techniques for Detecting Antibiotic Resistance in Helicobacter pylori: An Update and Clinical Applications

“…Currently, four phenotypic methods including the agar dilution method, broth microdilution method, disk diffusion test, and the Epsilometer test (or the E-test) are commonly used in clinical practice [7][8][9].…”

“…H. pylori suspension is added to each well containing one of the antibiotic dilutions, and the MIC is determined as the lowest concentration of the antibiotic that inhibits bacterial growth. This method is now increasingly used in epidemiological studies and clinical practice [9].…”

“…Currently, conventional culture-based microbiological methods are commonly used to determine the susceptibility of H. pylori strains to various recommended antibiotics [7][8][9][10][11]. However, these methods are tedious, time-consuming, costly, and, more importantly, invasive.…”

Inhibition of Salmonella Enteritidis by Essential Oil Components and the Effect of Storage on the Quality of Chicken

“…Then, 100 μL suspensions of S. Enteritidis were added to each well, each well was sealed, and each well was incubated for 48 h in ambient air at 37 °C to determine the results. The MIC is defined as the concentration where no visible bacterial growth is observed after 48 h of incubation at 37 °C under microaerophilic conditions [ 27 ].…”

Artificial intelligence-accelerated high-throughput screening of antibiotic combinations on a microfluidic combinatorial droplet system

“…However, due to the numerous types of antibiotics and their combinations, rapid screening of effective and safe antibiotic combinations with optimal dosage remains challenging. The conventional antimicrobial susceptibility assessment (AST), such as agar diffusion, 9 broth dilution, 10,11 and the Epsilometer test (E-test), 12,13 is typically applied for the evaluation of single antibiotics or a few simple antibiotic combinations, which does not comply with the requirements for the rapid screening of complexed antibiotic combinations. Recently, automated instruments for AST have been developed to provide rapid, accurate, and efficient testing.…”