Comparative performance of Filamentous Fungi 4.0 and Mass Spectrometry Identification 2.0 databases for Aspergillus...

Area of Science:

• Clinical microbiology
• Molecular diagnostics
• Mycology

Background:

• Aspergillus species cause pulmonary aspergillosis, presenting diagnostic challenges due to similar morphology.
• Accurate and rapid identification of Aspergillus species is crucial for effective patient management.

Purpose of the Study:

• To compare the performance of two spectral databases (FF_4.0 and MSI 2.0) for Aspergillus species identification using MALDI-TOF MS.
• To evaluate a simplified protein extraction method for routine use in clinical laboratories.

Main Methods:

• 46 clinical Aspergillus isolates were analyzed using MALDI-TOF MS with a simplified protein extraction from solid culture.
• Spectra were compared against Filamentous Fungi v4.0 (FF_4.0) and Mass Spectrometry Identification v2.0 (MSI 2.0) databases.
• Results were correlated with molecular identification (benA, cmd5, ITS sequencing).

Main Results:

• The MSI 2.0 database achieved 82.6% species-level identification, while FF_4.0 identified none at the species level.
• The simplified extraction method yielded high-quality spectra.
• Concordance between MSI 2.0 and sequencing was 44.7%.

Conclusions:

• The MSI 2.0 database combined with simplified protein extraction is efficient and suitable for routine clinical identification of Aspergillus species.
• This approach offers faster results compared to conventional methods.
• The FF_4.0 database demonstrated limited utility for hospital laboratory workflows.