RAPID DETECTION OF GRAM-POSITIVE BACTERIA AND RESISTANCE DETERMINANTS FROM POSITIVE BLOOD CULTURES USING MICRO-ARRAYBASED TECHNOLOGY.

OBJECTIVE: We present preliminary results, obtained by microarray-based technology, used for the fi rst time in Bulgaria / Verigene System, Nanosphere company, USA/, a new tool for rapid detection of Gram positive and Gram-negative pathogens in blood stream infections /BSI/ in comparing with conventional methods performed currently in our laboratory MATERIALS & METHODS: Hundred fi fty positive by Bactec 9050 / BD- USA/ and BacTalert systems Biomerieux- France/ bloodcultures / BC/ were investigated between May 2012 and February 2014. After the signal for positive BC and Gram staining, it was immediately performed the Verigene BC-GP, using 350 μl blood from the positive BC bottle for Gram-positive microorganisms detection RESULTS: The data show correct identifi cation for gram-positive bacteria investigated to genus level in 80% in the frame of 2.5 hours and reduction of turnaround time with 48h, compared with conventional methods after appropriate sub-culturing and identifi cation by Vitek 2 System / Biomerieux - France/. Additionally, the staphylococci tested for the presence of mecA gene in Verigene system showed 75.7% coincidence with cefoxitin test as well as they were identifi ed as methicillin resistant microorganisms by Vitek 2 system. CONCLUSION: The Verigene Gram-positive Nucleic Acid Test / BC-GP / is a very usefully tool of detection and identifi cation of potentially pathogenic Gram-positive bacteria which may cause bloodstream infections. [ABSTRACT FROM AUTHOR]