Time to Appropriate Antibiotic Between Using Microarray Assay and Mass Spectrometry Technique

Comparison of Time to Appropriate Antibiotic Between Using Microarray Assay and Mass Spectrometry Technique for Identification of Positive Blood Cultures

This is an experimental study of participants who had positive blood culture to compare time to appropriate antibiotic between using Microarray Assay and Mass Spectrometry to bacterial Identification.

Between June to Dec 2018, 200 participants those met the eligibility criteria were enrolled in this study that is a quasi experimental study. All participants were empirical antibiotic therapy by infectious physician. 100 patients in Pre-intervention group had bacterial identification by Mass spectrometry technique from bacterial colony and 100 patients in Post-intervention group had bacterial identification by Microarray assay from blood culture. Antibiotic adjustment were considered after bacterial identification and result of antibiotic susceptibility testing. Then all participants were re-evaluated outcome after treatment. Finally, the results were ready to analysis in January 2019.

100 participants received empiric antibiotic by ID physician, bacterial identification by Mass spectrometry technique

100 participants received empiric antibiotic therapy by ID physician, bacterial identification by Microarray assay from blood culture and confirm with Mass spectrometry technique

Bacterial identification by Microarray assay from positive blood culture and confirmed by Mass spectrometry technique from bacterial colony. Adjusted antibiotic therapy according to AST Re-evaluation after treatment

To compare the time to appropriate antibiotic therapy in patients with positive blood cultures between using Microarray assays versus Mass Spectrometry technique for Identification of Positive Blood Cultures

Comparison of time that participants received appropriate antibiotic therapy between 2 study period (Mass spectrometry technique and Microarray assay group)

To compare proportion of mortality between 2 study periods (Mass spectrometry technique and Microarray assay group) at 2 weeks after enrollment

To compare lengths of hospital stay between 2 study periods (Mass spectrometry technique and Microarray assay group)

To compare the cost of antibiotics for the course of treatment during study period between 2 study period (Mass spectrometry technique and Microarray assay group)

To compare percentage of De-escalation or escalation antibiotic between 2 study periods (Mass spectrometry technique and Microarray assay group)

Inclusion Criteria: Age ≥ 18 year old with positive hemoculture between June 2018 and Dec 2018 Internal medicine wards patients at Maharaj Nakorn Chiang Mai Hospital Ability to provide informed consent Exclusion Criteria: Suspected contaminated positive blood culture Bacteremia cause by more than two species of bacteria, as suspected from the gram staining examinations Terminally ill patients