Laser beam test identifies specific strain of bacterial infection
Toronto, November 10, 2015
By Heather Brown
Dr. Larissa Matukas, head of the Division of Microbiolog, inserts a stainless steel plate into the mass spectrometry device to identify a strain of bacteria. (Photo by Yuri Markarov)
Patients suffering from a bacterial infection such as strep throat or methicillin-resistant staphylococcus aureus are being prescribed the right medication sooner thanks to an innovative diagnostic test being used in St. Michael’s microbiology laboratory.
The test, known as the matrix-assisted laser desorption ionization time-of-flight mass spectrometry, can identify a strain of bacteria within seconds, which is what makes this test so advanced.
Traditional microbiology tests can take up to 24 hours to produce a result because the bacteria must grow in a small plastic dish, known as an agar plate, before a lab technologist can view it under a microscope and use a series of tests to identify it.
To produce the faster result, a lab technologist takes a sample of the growing bacteria and smears it onto one of the small indents on a small stainless steel plate, then places it into the machine. A laser beams onto the sample, breaking it into tiny particles. The particles are analyzed and matched to strains of bacteria in a database.
Physicians and nurse practitioners use the result to guide antibiotic prescription sooner to treat a patient’s infection instead of waiting for the traditional tests to identify the bacteria.
The lab started using the new test in January and processes approximately 150 tests per day.
“Not only has this test enhanced patient care at the hospital but it has also enabled our lab to operate more efficiently,” said Dr. Larissa Matukas, head of the Division of Microbiology at St. Michael’s. “We are able to report results sooner and have reduced our costs associated with bacterial organism identification.”
About St. Michael's Hospital
St. Michael’s Hospital provides compassionate care to all who enter its doors. The hospital also provides outstanding medical education to future health care professionals in 27 academic disciplines. Critical care and trauma, heart disease, neurosurgery, diabetes, cancer care, care of the homeless and global health are among the hospital’s recognized areas of expertise. Through the Keenan Research Centre and the Li Ka Shing International Healthcare Education Centre, which make up the Li Ka Shing Knowledge Institute, research and education at St. Michael's Hospital are recognized and make an impact around the world. Founded in 1892, the hospital is fully affiliated with the University of Toronto.