Performance of the ASTA MicroIDSys, a Novel MALDI-TOF MS Platform for Identifying Various Acinetobacter Species: Comparison with the Bruker Biotyper

Abstract

Background: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a rapid and reliable method for microorganism identification. Herein, we compared the performance of the recently developed ASTA MicroIDSys (ASTA, South Korea) with that of the Bruker Biotyper (Bruker Daltonics, Germany) for identifying various Acinetobacter species. Methods: A total of 207 specimens comprising 22 Acinetobacter type or reference strains and 185 clinical isolates previously identified using molecular methods were tested per the manufacturers' recommendation, and the obtained results were compared. Results: The overall correct identification rates at the species level using the Bruker Biotyper and the ASTA MicroIDSys systems were significantly different (P <0.001) at 89.4% (185/207) and 96.6% (200/207), respectively. The correct identification rates within the Acinetobacter baumannii (Ab) group were similar (P =0.094) at 94.9% (166/175) and 97.1% (170/175), respectively. However, the correct identification rates within the non-Ab group were significantly different (P <0.05), at 59.4% (19/32) and 93.8% (30/32), respectively. When the twelve strains were excluded as the species were absent from the Bruker database, the overall identification results did not differ significantly (P =0.289). Conclusions: Both instruments were suitable for identifying commonly isolated Acinetobacter species in clinical microbiology laboratories, showing equivalent performance for the Ab group, while the ASTA MicroIDSys identified the non-Ab group with higher accuracy than the Bruker Biotyper.