Winter 2012 - Douglass Hanly Moir Pathology

Rapid Identification of Bacterial Pathogens byMALDI-TOF Mass SpectroscopyNot many deliveries to Douglass Hanly Moir Pathology of large,shiny machines encased in bubble-wrap are addressed to theMicrobiology Laboratory, but that day has come at last.Douglass Hanly Moir Pathology is the first private laboratory inAustralia to begin using an instrument that is amongst the mostsophisticated available for the rapid and reliable identificationof bacterial and fungal pathogens. MALDI-TOF (Matrix-AssistedLaser Desorption Ionisation – Time of Flight) technology uses massspectroscopy (MS) to analyse bacterial and fungal cultures. This notonly allows much faster identification of potential pathogens, butprovides greater certainty of that identification.Dr Ian ChambersMicrobiologistMALDI-TOF-MS relies on thepremise that virtually every bacterialspecies, when analysed using massspectroscopy, has a unique “proteinsignature”, based on mass-chargeratio. Microbial identification is achievedby comparing the mass spectralprofile of the test organism with adatabase consisting of more than 500medically important bacteria and 70relevant fungi. If the required level ofconcordance is reached between testand reference profiles, identification hasbeen achieved.Routine use of this technology, overthe last decade in Europe and morerecently worldwide, has established itsclinical utility. More rapid identification ofpathogens (taking minutes rather thanthe 4-24 hours required by traditionalidentification methods) has translatedinto improved clinical outcomes.Dr Michael WehrhahnMicrobiologist10