Resistell Phenotech AST to Determine the Antibiotic Susceptibility of Gram-negative Bacteria Causing Bacteremia

Resistell Phenotech AST to Determine the Antibiotic Susceptibility of Gram-negative Bacteria Causing Bacteremia: a Prospective, Non-interventional, Multi-centric, Clinical Performance Study

The aim of this study is to assess the sensitivity, specificity, and accuracy of the Resistell Phenotech device in testing antibiotic susceptibility of Gram-negative bacteria (i.e., E. coli or K. pneumoniae) to clinically relevant antibiotics. The study is designed as a prospective, non-interventional, multi-center, single-arm study.

The blood culture samples from bacteremia patients that are positive for E. coli or K. pneumoniae will be tested with the Resistell Phenotech device after strain identification by MALDI-TOF. The results of the Resistell AST will be compared with the results from the disk diffusion tests (all sites use the Kirby-Bauer disk diffusion test), and site dependent tests (VITEK® 2, BD Phoenix™, MicroScan WalkAway system, and/or EUCAST RAST), which are currently the standard AST methods in the microbiology laboratories at the participating sites.

Inclusion Criteria:

• Patients who have signed a General Consent form approving use of their residual blood samples for research purposes (applicable at CHUV only)
• Patients who have signed a consent allowing the use of their residual sample (Restprobenerklärung) (applicable at MUI, only)
• Patients over the age of 18 years (>18)
• Patients with bacteremia considered to be due to E. coli or K. pneumoniae
• Patients whose positive blood cultures were not older than 24 hours at the time of AST start

Exclusion Criteria:

• Patients with documented refusal of the use of biological material for research purposes (applicable at CHUV, only)
• Patients with polymicrobial bacteremia