Burkholderia pseudomallei identification: a comparison between the API 20NE and VITEK2GN systems

Sixty unique clinical isolates previously reported as Burkholderia pseudomallei were run in parallel through the API 20NE and VITEK2GN identification systems after 24h growth on Columbia agar with 5% sheep blood. The identifications and confidence levels determined by each test modality were compared. The VITEK2GN identified 47 (78.3%) and the API20NE identified 52 (86.7%) of the isolates as B. pseudomallei. The modal octal profile for the latter was 1156577. The alternative identification most commonly made by both systems was B. cepacia. Comparison of the two modalities gave a Cohen's kappa of 0.6008, suggesting good overall inter-test agreement. Both are good test modalities capable of identifying B. pseudomallei reliably, with the API20NE having the advantage of correctly identifying a slightly greater number of isolates, and the VITEK2 having the advantage of a shorter test turnaround time.