Phenotypic profile of priority multiresistant Аcinetobacter baumannii sequence types (ST 1167, ST 944, ST 208)

Abstract

Introduction. About 1,000,000 cases of infections caused by Acinetobacter spp. per year are registered globally, making up 1.8% of all the cases of hospital-acquired infections. In compliance with long-term studies carried out in in this country and abroad, Acinetobacter baumannii is a clinically important representative of the Acinetobacter genus. Intraspecific typing of microorganisms is an integral part of a clinical microbiologist's contribution to scoring the outbreaks of purulent-septic infections within the sphere of HAI surveillance. Most of the practicing microbiological laboratories cannot use genotypic typing methods because of their high costs.Objective. Developing a test panel for intraspecific identification of A. baumannii sequence types (ST 1167, ST 944, ST 208) based on their phenotypic properties.Materials and methods. Intraspecific membership of 74 A. baumannii strains obtained from four multipurpose health settings of a large industrial centre was studied using a genetic method (multilocus sequence typing) and a suite of phenotypic methods (biochemical tests, biofilmogenous capacity, growth inhibition zones to antibacterial drugs, sensitivity to aniline dyes, disinfectants and Acinetobacter bacteriophage) was studied.Results. Phenotypic features of three predominant A. baumannii sequence types (ST 1167, 944, 208) were determined.Discussion. An efficacious economy set of differentiating tests allowing identification of intraspecific features of A. baumannii multiresistant strains was сreated.Conclusion. The test panel will enable the laboratories that cannot use sequencing methods to conduct intraspecific differentiation of common A. baumannii sequence types as part of microbiological monitoring.

Keywords

• acinetobacter baumannii
• intraspecific characteristic
• typing
• phenotypic properties
• sequence type