Identification of Infectious Diseases Patterns in the Combined Use of Bacteriological Diagnostics and MALDI Biotyper

Abstract

In multidisciplinary hospitals, there are conditions conducive to the emergence of healthcare-associated infections: high concentration of people with reduced immunity in a limited area, the presence of a significant number of sources of contagion (patients and carriers), a change in the biocenosis of the mucous membranes and skin of patients and medical personnel under the influence of widespread use of antibiotics and cytostatics. The aim of the research was in the intercomparison of the standardized bacteriological algorithms and the MALDI Biotyper system in the microbiological diagnosis of pathogens as illustrated by the healthcare-associated diseases.Materials and methods. Seventy-eight patients of a multidisciplinary hospital of a regional level (Irkutsk) in 2018–2019 were examined. The age of patients ranged from 1 to 15 years. The material for the study was blood, sputum, swabs from the tracheobronchial tree, throat, nose, wound, abdominal fluid, cerebrospinal fluid, and swabs from environmental objects. Identification of the isolated cultures (78 bacterial strains) was carried out using generally accepted bacteriological methods, as well as using the MALDI Biotyper system.Results and discussions. In the structure of healthcare-associated infections, Pseudomonas aeruginosa occupied a leading position. Not all isolates of microorganisms were identified by standardized bacteriological methods. The identification of strains with characteristic manifestations of physiological and biochemical characteristics was more reliable. Identification difficulties arose in the presence of atypical properties of microorganisms when the use of MALDI Biotyper would be crucial.Conclusion. It is necessary to apply an integrated approach to conduct reliable diagnostics of pathogens. It includes standardized bacteriological methods and methods for identifying microorganisms using mass spectrometry in the subsequent stages.

Keywords

• bacteriological diagnostic
• mass spectrometry
• healthcare-associated infections
• non-fermentative microorganisms
• pseudomonas aeruginosa
• stenotrophomonas maltophilia
• klebsiella pneumoniae