Rapid Detection of Specific Gram Negative Microorganisms Causing Bloodstream Infections in Children with Microarray Method

INTRODUCTION: Bloodstream infections are serious conditions that can cause significant morbidity and mortality. Early recognition of the bacteria and targeted early treatment play an important role in prognosis. The Verigene Gram-negative blood culture nucleic acid test (BC-GN; Nanosphere, USA) is a new method that can accurately identify both Gram-negative bacteria and resistance gene within 2 hours. In this study, we aimed to determine the accuracy of this assay for the rapid identification of certain Gram-negative microorganisms in children with bloodstream infections and to compare with conventional culture method.
METHODS: A total of 30 patients (<18 years-old) with bloodstream infections due to Gram negative bacteria were prospectively included who were followed up in the Department of Pediatrics of Ege University Faculty of Medicine between December 2015-June 2016. Microarray test results were compared with conventional blood culture results.
RESULTS: Klebsiella spp. (40%) were the most common, Acinetobacter spp. (20%) were the second most common Gram negative microorganisms. Accurate identification of microarray analysis was 100% (12/12) for Klebsiella spp, 100% (6/6) for Acinetobacter spp., 100% (5/ 5) for E. coli, 80% (4/5) for Enterobacter cloacae spp., 100% (1/1) for Pseudomonas aeruginosa and 100% (1/1) for Citrobacter amalonaticus, respectively. The test was able to correctly identify 96.5%. of Gram negative microorganisms that were located in the test panel. CTX-M was the most common gene responsible for the resistance.
DISCUSSION AND CONCLUSION: Verigene Gram negative (BC-GN) microarray test (Nanosphere) is a rapid method which can correctly identify the located Gram-negative microorganisms in the panel and results much faster than the conventional methods.