How does MALDI-TOF contribute to rapid identification but not to antimicrobial susceptibility?

How does MALDI-TOF contribute to rapid identification but not to antimicrobial susceptibility?

• A. It rapidly identifies organisms at the species level, but does not provide susceptibility data unless paired with additional testing.
• B. It provides MIC values.
• C. It detects resistance genes.
• D. It measures growth rate.

Answer: (A)

MALDI-TOF works by measuring the protein fingerprints of a microorganism and matching them to a reference database, which allows rapid identification at the species level once a culture is available. This speed helps guide initial therapy by knowing exactly what organism is present, but the method does not assess how that organism would respond to antibiotics. Antimicrobial susceptibility requires testing the organism’s growth in the presence of antibiotics or detecting resistance genes, which MALDI-TOF in its standard form does not provide. To get MIC values or susceptibility categories, MALDI-TOF identification is paired with dedicated susceptibility tests (like broth microdilution, disk diffusion, or molecular resistance assays). Some workflows may add supplementary tests to infer resistance, but the primary output of MALDI-TOF is rapid identification, not susceptibility.

MALDI-TOF works by measuring the protein fingerprints of a microorganism and matching them to a reference database, which allows rapid identification at the species level once a culture is available. This speed helps guide initial therapy by knowing exactly what organism is present, but the method does not assess how that organism would respond to antibiotics. Antimicrobial susceptibility requires testing the organism’s growth in the presence of antibiotics or detecting resistance genes, which MALDI-TOF in its standard form does not provide. To get MIC values or susceptibility categories, MALDI-TOF identification is paired with dedicated susceptibility tests (like broth microdilution, disk diffusion, or molecular resistance assays). Some workflows may add supplementary tests to infer resistance, but the primary output of MALDI-TOF is rapid identification, not susceptibility.