Title : Diagnostic Accuracy of Rapid Assays for Diagnosis of Bloodstream Infections And Antimicrobial Profiling of Pathogens That Causes Bloodstream Infections At a Tertiary Hospital In Polokwane, Limpopo Province, South Africa
Abstract:
Background: Antimicrobial resistance is a cause of high morbidity and mortality in South African hospitals. Turnaround time for diagnosis of bloodstream infections is long, rendering results clinically irrelevant. Thus, there is a need for a faster and more accurate diagnosis platform for diagnosis of BSI. The aim of this study was to evaluate the performance of the BioFire Film Array BCID2 machine for rapid identification (ID) compared with the standard of VITEK 2 workflow for Identification and antimicrobial susceptibility testing (AST).
Methods: We conducted a prospective cross-sectional study in patients suspected of having Bloodstream infections at Pietersburg Hospital, Polokwane, South Africa from January to May 2023. The blood cultures were incubated in the BD Bactec machine. The positive blood cultures were run on the VITEK 2 and BioFire Film Array BCID2 machines, to identify the pathogens, their AMR genes, as well as their antimicrobial susceptibility patterns. The results were loaded on excel and analysed using Statistics and Data (STATA) latest version.
Results: Of the pathogens that were isolated from the positive blood cultures, most of them were Gramnegative bacilli. The most common organisms isolated were Acinetobacter baumannii complex constituting 30%, followed by Enterobacter cloacae complex with 24%, Klebsiella pneumoniae group with 18%, Escherichia coli with 15%, and Pseudomonas aeruginosa with 12%. The AMR genes identified were mecA/C gene (33%), CTX-M (33%), NDM (18%), OXA-48 Like (12%), and VIM (3%). Of all the antimicrobials tested, ampicillin (82%), cefotaxime (77%), and trimethoprim-sulfamethoxazole (76%), showed the highest level of resistance. Most pathogens were isolated from male patients (48%), and from children between 0 to 5 years (48%).
Conclusion: The BCID2 provides a faster and more accurate diagnosis of BSI as compared to the traditional culture methods and VITEK2. The BioFire FilmArray BCID2 allowed species ID and carbapenemase detection within around 1 h after blood culture positivity, which is a significant reduction in the turnaround time of the PBC workflow. There is a significant rise in the statistics of Carbapenem-resistant organisms. The impact of multidrug-resistant organisms may be reduced in the future with the use of novel antimicrobial methods, modified usage of antimicrobial agents, public health measures, and the use of more rapid molecular assays. Keywords: Bloodstream Infections, Diagnostic Accuracy, Antimicrobial Profiling
