The false positive signals of a continuous monitoringblood culture system (CMBCS) increase the reportingtime and laboratorycost. This study aimed to determine the highly relevant variables that discriminate false positive signals from true positive signals in a CMBCS.
METHODS:
Among 184,363 blood culture sets (aerobic and anaerobic), the signal-positive samples according to a BACTEC FX system (Plus Aerobic/F, BDA; Plus Anaerobic/F, BDN) and BacT/Alert 3D system (Standard Aerobic, BSA; Standard Anaerobic, BSN) between April 2010 and November 2013 were classified into two groups false positive or true positive signals. The data of 15 parameters between the two groups were then statistically compared.
RESULTS:
Among total blood cultures, the positive rates of CMBCS signals according to BDA, BDN, BSA, and BSN were 4.9%, 2.8%, 3.8%, and 3.2%, respectively. The false positive rates of CMBCS signals according to BDA, BDN, BSA, and BSN were 0.6%, 0.1%, 0.1%, and 0.1%, respectively. The blood volume, detectiontime, time interval between admission and test, C-reactive protein concentration, leukocyte count, deltaneutrophil index, and mean peroxidase index showed statistically significant differences between the two groups.