Efficacy of Blue-CARBA Test for Detection of Carbapenemase in Acinetobacter baumannii Isolated from Burn Patients

Background: Resistance to carbapenem as a most effective antibiotic for treatment of Acinetobacter baumannii infection can make a complication in treatment of patients. Several phenotypic methods have been introduced for detection of the carbapenemase producing strains. The aim of this study was determined the efficacy of the newest method that is called Blue-CARBA test for identification of the carbapenemase producing Acinetobacter baumannii. Methods: In this cross sectional study 63 Acinetobacter baumannii have been collected from burn wounds infection. Carbapenem susceptibility testing has been conducted by disc diffusion agar method after identification The Modified Hodge test and Blue-CARBA test was performed for all carbapenem resistant strains. Vim, imp, oxa-23, oxa-48, NDM-1, SPM-1 and kpc genes have been detected as a most common carbapenemase in Acinetobacter baumannii. Results: Sequence analysis showed that 54 isolates include oxa-23 gene. Eight and 5 strains carried vim and kpc genes respectively. MHT and Blue-CARBA test were positive in 27 and 28 of imipenem resistant strains, respectively. Conclusion: According to the results of this study, Blue-CARBA test showed similar power of carbapenemase producing identification with Modified Hodge test and can be purposed use in place of MHT for detection of carbapenemase.