Diagnostic Accuracy of the Biofire FilmArray Blood Culture Identification 2 (BCID2) for Bloodstream Infections in Limpopo, South Africa

Abstract

Background: Bloodstream infections are a leading global cause of mortality and morbidity. Timely and accurate diagnosis improves outcomes, especially in resource-limited settings. Rapid and accurate diagnostic tools are essential for effective treatment, particularly in resource-limited settings. Our study aimed to evaluate the diagnostic performance of the BCID2 assay, comparing its effectiveness to the VITEK2 at a routine lab in Limpopo, South Africa, where alternative assays are necessary to overcome resource unavailability in areas located further away from major laboratories. Methods: This cross-sectional study was conducted from August to December 2023. A total of 247 positive blood culture bottles were tested using both BCID2 and VITEK2 systems. Statistical analysis, including specificity, sensitivity, and accuracy, was calculated using Medcalc and SPSS. Results: The BCID2 panel demonstrated a sensitivity, specificity, and accuracy of 95.7%, 95.5%, and 96%, respectively. Of the samples, 72% (179/247) were monomicrobial and 28% (68/247) were polymicrobial, with a total of 16 off-panel microorganisms identified across both groups. blaCTX-M was the most frequent Gram-negative resistance gene detected (55.2%, 80/145), while blaVIM was the least common (0.7%, 1/145). Conclusion: The study concluded that the BCID2 assay demonstrates excellent diagnostic accuracy, with sensitivity, specificity, and overall accuracy rates above 95%. Its ability to rapidly detect bloodstream infections and antimicrobial resistance markers makes it a highly effective tool, particularly in resource-limited settings like Limpopo, South Africa, where timely and accurate diagnosis is crucial to improving patient outcomes.