As we approach the 1 year anniversary of the MALDI-TOF in the ADDL, we’re excited to update you on its use. What’s the MALDI-TOF? It is a mass spectrometer that uses a laser to blast proteins into small pieces that then travel through a vacuum tube with a detector waiting at the other end. The detector captures a spectrum which can be used to analyze the sample.

The bacteriology lab uses the MALDI-TOF to directly analyze bacterial colonies. A software program maps the spectra to a proprietary database, and a match results in identification of the organism. This entire process occurs within just a few minutes. Because of our quality standards, we perform in-lab verification prior to reporting results generated through new methods. During the past year, we have verified 27 bacterial identifications on the MALDI-TOF for reporting without further biochemical testing, and we are continually testing more bacterial species. One MALDI-TOF verification/methods-development study was presented by one of our bacteriology technicians, Manny Benitez, at the National AAVLD annual meeting this fall.

What does this mean for our clients? Because the MALDI-TOF can identify bacteria directly from a colony, we are often able to report results within 24 hours of receiving a sample in the lab. Compare that to using standard biochemical tests like you learned in school which at best can give you a result within 48 hours of the sample’s arrival in the lab. Antimicrobial susceptibility testing requires an overnight incubation, so MIC results are usually available the day after the species identification. Faster results allow you to make management decisions sooner.

In the next issue we’ll update you on what’s happening with the MALDI-TOF in the toxicology lab.