Poster Presentation Australian Society for Microbiology Annual Scientific Meeting 2016

Species Level Identification and Clinical Features of Actinomyces spp. using Bruker Daltonics Microflex LT system (MALDI TOF) in a Clinical Microbiology Laboratory (#268)

Peivern Fong 1
  1. Monash Health, MELBOURNE, VIC, Australia

There has not been much light shed on the performance of matrix­assisted laser desorption ionization­time of flight mass spectrometry (MALDI­ TOF) BRUKER on the identification of Actinomyces. Actinomyces are fastidious bacteria and the identification of the organisms have been proven cumbersome, challenging and time consuming. Actinomyces also resemble other diphtheroid­like Gram positive rods such as Corynebacterium species and are therefore often presumptively identified in laboratory as diptheroids based on their morphology and reported as diptheroids of doubtful or uncertain significance or dismissed as part of the commensal skin flora. The bacterial infection is described as an uncommon and progressively invasive infection, resulting in fistulas and purulent or bloody discharge from sinuses which may discharge sulphur granules.

 

MALDI­TOF has been proven effective in recent studies in bacterial identification, even for those that are fastidious and slow growing. Therefore, the validation of the performance of MALDI­TOF on the identification of Actinomyces spp. will significantly improve the turnaround time if proven reliable and accurate. Rapid identification allows prompt intervention as Actinomycosis requires prolonged and high doses of antibiotics. Studies on the usage of MALDI­TOF in the identification of Actinomyces species are scarce compared to other groups of bacteria. One recent study showed the VITEK MS MALDI performed poorly compared to 16srRNA gene sequencing for identification of Actinomyces spp. but similar studies are lacking for the Bruker MALDI­TOF system. All Actinomyces isolates will be sequenced and identified using BRUKER MALDI TOF.