Organism Identification by Matrix-assisted Laser Desorption/Ionization Time-of-Flight MS With Reflex to Sequence-based Identification
Also known as: MALDI-TOF Organism Identification
Use
Determine the identification of isolates (ie, bacterial, mycobacterial, etc) from another laboratory that has performed culture of the clinical specimen. These isolates may include strict aerobes, facultative anaerobes, anaerobes, yeast, mycobacteria, Nocardia and/or Actinomycetes.
Special Instructions
Susceptibility testing may be requested for an additional charge. Clients are instructed to provide Labcorp with clinical and testing information on procedures already performed, which aids in expediting testing on receipt. It is noted that broth medium containing a pure culture may be submitted for testing; however, performing subculture to solid media prior to MALDI testing will require additional time. If the organism identification is not obtained using MALDI-TOF, the test will reflex to identification via ITS gene sequencing.
Limitations
The MALDI-TOF technology for organism identification is limited to what is available in the spectral database. If the organism is not represented in this database, the test will reflex to ITS gene sequencing for identification. The process also involves challenges if the sample comprises nonviable organisms, is incorrectly labeled, or is transported under inappropriate conditions. Furthermore, mixed cultures or discrepancies in specimen names between forms can lead to rejection.
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 76346-6
- 76346-6
Result Turnaround Time
5-15 days
Related Documents
For more information, please review the documents below
Specimen
Cultured Cells
Volume
Pure culture (visible colonies should be present)
Minimum Volume
Viable colonies macroscopically visible on culture medium; one bacterial culture transport swab with media.
Container
Bacterial swab transport inoculated with the isolate from a pure culture or agar slant in screw-cap container packed as an etiologic agent.
Collection Instructions
Maintain a subculture at the submitting laboratory.
Storage Instructions
Room temperature
Causes for Rejection
Isolate nonviable; unlabeled specimen or name discrepancy between the specimen and the name in the computer or on the test request form; isolate transported under inappropriate conditions; broken tube or plate; mixed culture; single specimen identifier
Other tests from different labs that may be relevant