Evaluation of the MALDI-TOF MS method for routine identification of Candida species in a tertiary care hospital in Thailand

Abstract

Aims: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is increasingly used to identify Candida spp. in diagnostic laboratories due to its strength in providing accurate information results, speed and cost-effectiveness. However, its accuracy varies on instrument platform, reference database, sample preparation techniques and interlaboratory comparisons. Therefore, the use of MALDI-TOF MS for species identification was evaluated against traditional biochemical identification, namely BrillianceTM Candida and Remel RapIDTM Yeast Plus System. Methodology and results: To evaluate and compare identification efficiency, turnaround time and consumable cost, 194 clinical isolates of Candida were collected. The results showed overall 85.6% concordant identification between two methods with 94.9-99.5% and 100% accuracy in traditional and MALDI-TOF MS, respectively, in the identification of four common Candida species; C. albicans, C. tropicalis, C. parapsilosis sensu stricto and C. glabrata sensu stricto. Other Candida species were also identified with 85.6% and 97.5% accuracy rates by traditional and MALDI-TOF MS, respectively. Additionally, identification using MALDI-TOF MS reduced overall turnaround time and cost by approximately 99.8% and 86.5%, respectively. Conclusion, significance and impact of study: This study highlights the performance of MALDI-TOF MS, which is more accurate in identifying Candida spp. with a less hands-on approach, cheaper cost and shorter turnaround time.