A high-throughput cell culture system based on capillary and centrifugal actions for rapid antimicrobial susceptibility testing.

Antibiotic resistance is a global threat to modern society. Rapid determination of suitable antibiotics that inhibit bacterial growth can effectively reduce antibiotic resistance and improve clinical treatment. The conventional methods of antimicrobial susceptibility testing (AST) depend on optical density measurements, which require long-time incubation. Various kinds of rapid AST systems which utilize various technologies from the field of lab on a chip have promised a great reduction in measurement time, but cannot achieve high-throughput, user-friendly testing due to the complexity of the testing system. Here, we introduce a capillary and centrifuge-based rapid AST system that reduces the time of loading the sample and culture media while achieving a high-throughput testing capacity. The capability of the proposed system is validated in a systematic analysis that includes sample loading characteristics and AST trials with standard strains. The proposed system provides a useful tool for drug testing in cell-culture systems with user-friendly and high-throughput analysis.

Direct, rapid antimicrobial susceptibility test from positive blood cultures based on microscopic imaging analysis.

For the timely treatment of patients with infections in bloodstream and cerebrospinal fluid, a rapid antimicrobial susceptibility test (AST) is urgently needed. Here, we describe a direct and rapid antimicrobial susceptibility testing (dRAST) system, which can determine the antimicrobial susceptibility of bacteria from a positive blood culture bottle (PBCB) in six hours. The positive blood culture sample is directly mixed with agarose and inoculated into a micropatterned plastic microchip with lyophilized antibiotic agents. Using microscopic detection of bacterial colony formation in agarose, the total time to result from a PBCB for dRAST was only six hours for a wide range of bacterial concentrations in PBCBs. The results from the dRAST system were consistent with the results from a standard AST, broth microdilution test. In tests of clinical isolates (n = 206) composed of 16 Gram-negative species and seven Gram-positive species, the dRAST system was accurate compared to the standard broth microdilution test, with rates of 91.11% (2613/2868) categorical agreement, 6.69% (192/2868) minor error, 2.72% (50/1837) major error and 1.45% (13/896) very major error. Thus, the dRAST system can be used to rapidly identify appropriate antimicrobial agents for the treatment of blood stream infection (BSI) and antibiotic-resistant strain infections.