Search

The culture method continues to be the "gold" standard for microbiological diagnosis of bloodstream infections. This is primarily due to the fact that the definition of the etiology of a generalized infectious process determines the etiotropic antibiotic therapy. To do this, it is necessary to conduct periodic microbiological monitoring of the prevailing microflora. To do this, in the present study, a retrospective analysis of the results of a microbiological blood test for sterility was performed in case of suspected bloodstream infections in a multidisciplinary hospital to assess the influence of analytical stage factors on the laboratory data obtained. Automatic hematological cultivators were used, identification was carried out based on the biochemical characteristics of microorganisms, as well as using time-of-flight mass spectrometry with matrix-activated laser desorption / ionization (MALDI-TOF MS). More than 10,000 research results were analyzed, the average microflora seeding rate was 15.1%. The analysis of the isolated microflora was carried out in 2 groups of positive results: at the beginning, the data obtained in the presence of growth in two vials at once were evaluated, then the positive results of blood cultures obtained in any one vial from a pair were studied. The predominance of gram-positive flora in the structure of microorganisms isolated from whole blood was revealed, the influence of cultivation conditions and the composition of thenutrient medium on the isolated flora was not found, however, a number of microorganisms, due to the specific characteristics of metabolism, were characterized by growth under strictly defined cultivation conditions. The presented study actualizes the need for constant microbiological monitoring in order to determine the prevailing hospital microflora, which can contribute to a timely response in order to limit the spread of highly virulent, aggressive, resistant strains of microorganisms leading to the development of generalized bloodstream infections., Competing Interests: The authors declare no conflict of interest.

The rapid spread of a new coronavirus infection in the country actualizes the conduct of bacteriological studies of clinical material obtained from the respiratory tract of patients with COVID-19. During the experiments, 230 sputum samples and 260 autopsy lung samples from patients with COVID-19 were analyzed. 946 high-risk strains were isolated and identified by MALDI-ToF mass spectrometry on a Microflex LT instrument (Bruker®). According to the results of bacteriological cultures of sputum, a predominance of gram-positive ones was revealed, amounting to 50.5% (222 strains) of the total number of isolated pathogens. However, falling into this group is manifested by natural representatives of the microflora of the human mucous membranes from the genera Streptococcus, Rothia and Lactobacillus (109 strains in total), which can be manifested by the detection of improper sputum collection, causing contamination by the substance of intense salivation and nasopharyngeal discharge. In turn, the "classic" gram-positive causative agents of pneumonia were detected much less frequently: S. aureus in 5 cases, S. pneumoniae in 6 patients. The causative agents in the order Enterobacterales are represented by 42 strains, among which the most likely species are K.pneumoniae (27 strains). In the group of non-fermenting gram-negative bacteria, A. baumanii (29 strains) prevailed, and P. aeruginosa was also identified in 2 cases. When analyzing the results of a microbiological study of autopsy material (lungs) of patients with COVID-19, significant differences in the qualitative and quantitative composition of the microflora were revealed, compared with sputum. In the group of gram-positive bacteria, 15 strains of the natural microflora of the mucous membranes were identified, while sensitive species dominated among gram-negative pathogens: K. pneumoniae (102 strains), A. baumanii (75 strains), P. aeruginosa (11 strains). Regular microbiological monitoring is essential for antibiotic therapy and prevention of secondary bacterial infection. In the event of a fatal outcome, the results of microbiological analysis of autopsy material can determine the cause of death of the patient., Competing Interests: The authors declare no conflict of interest.

Stenotrophomonas maltophilia is a common opportunistic microorganism and an important respiratory pathogen in cystic fibrosis (CF). The aim of this study was to determine antimicrobial resistance phenotypes, sequence-types (ST) and genetic determinants of antibiotic resistance in S. maltophilia strains recovered from CF patients in Russia. S. maltophilia isolates recovered from 170 CF patients were analyzed. Minimum inhibitory concentrations of antibacterial agents were determined using Sensititre Gram Negative GNX2F plates and the results were interpreted according to Clinical and Laboratory Standards Institute (CLSI) criteria. Whole-genome sequencing (WGS) was performed on MGISEQ-2000 platform. SPAdes software, Galaxy, ResFinder, Integrall and PubMLST were used for analysis of WGS data. S. maltophilia strains were identified from 24/170 (14%) CF patients. In total, 25 isolates were detected, two strains were isolated from the same patient. The isolates belonged to 17 different STs, including 5 new STs; ST4 was the most prevalent ST. Resistance to ceftazidime was observed in 60% of strains, to ticarcillin-clavulanate - in 32%, to levofloxacin - in 24%, to trimethoprim/sulfamethoxazole - in 12% of strains. All isolates were susceptible to minocycline. All ST4 isolates were resistant or intermediate to ceftazidime and ticarcillin-clavulanate. In two isolates, the sul1 gene was detected. In one isolate, sul1 was part of a class 1 integron. The detected integron also contained the blaGES-7 and aac(6')-Ib-cr genes. The ST4 sequence-type was the most prevalent ST among S. maltophilia strains recovered from CF patients in Russia. Antibiotic resistance genes, including sul1, blaGES-7, aac(6')-Ib-cr, were detected in single strains., Competing Interests: The authors declare no conflict of interest.

Cystic fibrosis (CF) is a common genetic disease, manifested by airway obstruction and chronic respiratory infection. The most prevalent infectious agent in airways of CF patients is Pseudomonas aeruginosa. This study aimed to determine sequence-types, antimicrobial resistance phenotypes and genes defining adaptive antibiotic resistance in P. aeruginosa isolates recovered from CF patients in Russia. In total, 84 P. aeruginosa strains from 64 CF patients were analyzed. Susceptibility to antibiotics was determined by disk diffusion test. Whole-genome sequencing (WGS) was performed on MGISEQ-2000 platform. SPAdes software, Galaxy, ResFinder, PubMLST were used for analysis of WGS data. Examined P. aeruginosa isolates belonged to 53 different sequence-types (STs), including 6 new STs. High-risk epidemic clone ST235 (10%) and clonal CF P. aeruginosa strains ST17, ST242, ST274 (7%) were detected. Non-susceptibility to ticarcillin-clavulanate, cefepime, imipenem was observed in 63%, 12% and 25% of isolates, respectively; to tobramycin - in 24%, to amikacin - in 35%; to ciprofloxacin, levofloxacin - in 35% and 57% of strains, respectively. Multidrug-resistant phenotype was detected in 18% of isolates. In examined strains, genes of beta-lactamases VIM-2 (5 ST235 strains), VEB-1 (two ST2592 strains), GES-1 (1 ST235 strain), PER-1 (1 ST235 strain) were found. Ciprofloxacin-modifying enzyme CrpP gene was detected in 67% of isolates, aminoglycoside-modifying enzymes AAD, ANT, AAC genes - in 7%, 4%, 12% of strains, respectively. P. aeruginosa isolates from CF patients in Russia demonstrate a high clonal diversity, which is similar to other P. aeruginosa infections. The isolates of high-risk clone and clonal CF P. aeruginosa strains are detected., Competing Interests: The authors declare no conflict of interest.

Recently, more and more scientific works have been devoted to non-tuberculous mycobacteria, both by domestic and foreign researchers. One of the main reasons for this is the increase in patients with immunosuppression of various origins, improvement of the quality of laboratory and instrumental diagnostics of mycobacteriosis. This article focuses on the representatives of the M. fortuitum group, as the main pathogens among the group of fast-growing mycobacteria. The data on the modern classification based on the use of molecular genetic studies are indicated. The M. fortuitum group includes: Mycobacterium fortuitum, M. peregrinum, M. senegalense, M. porcinum, M. houstonense, M. neworleansense, M. boenickei, M. conceptionense, M. septicum, M. alvei. According to the new data, mycobacteria were divided into 5 clades (Abscessus-Chelonae, Fortuitum-Vaccae, Terrae, Triviale, Tuberculosis-Simiae), and based on molecular genetic studies, new genera in the Mycobacteriaceae family were isolated: Mycolicibacter spp., Mycolicibacillus spp., Mycolicibacillus spp., Mycobacteroides spp., Mycolicibacterium spp. In accordance with the new classification, representatives of the Mycobacterium fortuitum group belong to the genus Mycolicibacterium. The main epidemiological features of the main sources of the spread of mycobacteria, factors and ways of their transmission are indicated. Due to their wide distribution in the environment, representatives of the M. fortuitum group are capable of causing diseases of the pulmonary and extrapulmonary localization. The distinctive features of pathogenicity factors, due to which the course of the disease is determined, are noted. The article also indicates the main difficulties and features of determining the sensitivity to antimicrobial chemotherapy drugs, provides data on the main features of antibiotic resistance of M.fortuitum group. In preparing the review, literature sources obtained from international and domestic databases were used: Scopus, Web of Science, Springer, RSCI., Competing Interests: The authors declare no conflict of interest.

The aim of the work was to determine and compare the structure of microorganisms isolated from bronchoalveolar lavage from patients in the ICU of Clinics in 2016 and 2019. This work presents the results of a bacteriological examination of 229 samples from 139 patients for 2016 and 387 samples from 218 patients for 2019. The predominant microorganism in 2016 was Acinetobacter baumanii - 75 (26.2%). Less common were Klebsiella pneumoniae - 55 (19.2%), Pseudomonas aeruginosa - 35 (12.2%), Escherichia coli - 19 (6.6%). In 2019, the prevailing microorganism was K.pneumoniae - 158 (19.1%). As in 2016, A.baumanii - 115 (13.9%) and P. aeruginosa - 57 (6.9%) were most often found, but unlike 2016, in 2019 there was a high incidence of such pathogens as Enterococcus faecalis - 52 (6.3%), Candida albicans - 43 (5.2%), Staphylococcus aureus and Stenotrophomonas maltophilia - 40 (4.8%). One of the features is the presence of polymicrobial associations. In 2016, microorganisms isolated in monoculture predominated (53.4%), while in 2019 the frequency of occurrence of monocultures decreased and amounted to 24.7%. At the same time, a two-component association prevailed (31.5%). Thus, in ICU it is necessary to regularly monitor nosocomial pathogens not only to make the right decision when choosing antimicrobial therapy, but also to identify new potential nosocomial pathogens., Competing Interests: The authors declare no conflict of interest.

The article presents data on the structure of acid-resistant members of the order Actinomycetales and rare species that have been isolated and identified using various methods. The study included strains of non-tuberculous mycobacteria (NTM) isolated from clinical material during examination for tuberculosis in the period from 2016 to 2019. The total number of samples with signs of NTMs growth that were included in the study was 316 samples. Primary isolation on Levenshtein-Jensen, Finn II, and MGIT media and NTMs identification by DNA-hybridization. All strains that were not identified prior to the species and culture, identified as microorganisms with a high G+C content (High GC GR +) were re-identified using a MALDI-ToF Microflex LT mass spectrometer (Bruker®). By the method of DNA-hybridization, 188 strains isolated by NTM were successfully identified to form 58.5% of all selected cultures. Among the selected species, representatives of slowly growing NTMs (M. avium complex, M. gordonae, M. kansasii) predominated, which amounted to 67.0% of all NTM strains identified to the species. Among the cultures for which DNA hybridization failed to carry out acceptable identification, predominantly NTMs were found, among which M. gordonae, M. avium, M. kansasii dominated. A number of NTMs were represented by rare species: M. iranicum and M. pseudoshottsii. Among this group of microorganisms, other acid-resistant aerobic actinomycetes were isolated, including those of potential clinical significance: Gordonia spp., Tsukamurella spp., Rhodococcus spp., Nocardia spp. When identifying cultures containing high concentrations of G+C, the maximum number of microbial associations was revealed, including those consisting of two types of NTMs (M. monacense + M. flavescens, M. avium + M. kansasii), as well as associations of M. gordonae with staphylococci. The same group included rare NTM species: M. fredericbergense, M. szulgai, M. malmoense, M. bohemicum, M. septicum, as well as representatives of the genera Nocardia, Gordonia, Tsukamurella., Competing Interests: The authors declare no conflict of interest.

More and more publications appear in the modern literature on the increase in the prevalence of non-tuberculous mycobacteria (NTMs), in particular, representatives of M. chelonae / Mycobacterium abscessus complex (MABSc). The paper presents data on the current classification of M. chelonae / Mycobacterium abscessus complex and its main representatives. The main data on the possible sources and ways of infection of MABSc patients in hospital are presented. The main features of cultivation on various nutrient media and their possible identification using modern methods are also indicated. The main risk factors for the development of mycobacteriosis in patients and the possible clinical picture are described. The prevalence of MABSc representatives in the structure of non-tuberculous mycobacteria isolated from clinical material from 483 patients from the Samara region was assessed for examination for tuberculosis, and the prevalence from 933 patients with cystic fibrosis (CF) from 55 regions of the Russian Federation from 2016 to 2019 was estimated. In total, as a result of the study, 316 NTM strains (65.4%) were isolated and identified in the first group of patients. M.abscessus was isolated and identified 10 strains and 5 strains - M.chelonae, which amounted to 3.2% and 1.6%, respectively, of all NTMs. In general, MABSc representatives were isolated in 3.1% of the examined patients. As a result of a screening study of patients with CF, 14194 microorganism strains from 933 patients were isolated and identified. Altogether M. abscessus was isolated and confirmed from 14 patients of different ages. Thus, the prevalence of MABSc among the examined patients with CF in the Russian Federation was 1.5%., Competing Interests: The authors declare no conflict of interest.

The structure of the microflora of the urogenital tract of a woman is variable and diverse, changing its qualitative and quantitative composition can affect various physiological processes in the body of a woman, including the course of pregnancy. In this study, the results of cultures of 1415 samples of urine and cervical canal discharge of pregnant women were analyzed. Species identification was carried out by MALDI-ToF mass spectrometry using Microflex LT (Bruker) mass spectrometer. Gram-positive bacteria (69.5%) dominated the structure of the cervical canal microflora, among which Staphylococcus spp prevailed., Enterococcus spp. and Lactobacillus spp. Among gram-negative bacteria most often encountered microorganisms of the order Enterobacteriales, the predominant species among which was E. coli. Also, yeast-like fungi were isolated from the material of the cervical canal, their number was 11% of the total number of crops. Qualitative microbiological composition of urine was represented by gram-positive flora (68.7%), gram-negative flora (30.1%) and Candida fungi (1.2%). There is a significant predominance of coagulase-negative staphylococci (97.3%) over coagulase-positive (2.7%) in the structure of gram-positive microorganisms. The composition of gram-negative flora is mainly represented by bacteria of the order Enterobacteriales (71.4%). The study identified microorganisms that can cause postpartum complications and the development of inflammatory diseases of the newborn, which suggests the need for regular microbiological examination for pregnant women., Competing Interests: The authors declare no conflict of interest.

The aim of the study was to determine the comparative significance of basal metabolism indicators and inflammatory process markers for the closest prognosis of patients in ICUs with systemic inflammation syndrome caused with infectious genesis. The paper presents the results of a retrospective analysis of the plan of treatment of 198 patients with confirmed clinical and laboratory signs of bacterial infection. The number of leukocytes, platelets, the percentage of lymphocytes, the concentration of procalcitonin, creatinine, bilirubin, C-reactive protein, acid-base balance values were determined in patients. Patients were assessed on a SOFA scale. The type of biomaterial for microbiological research was determined depending on the intended source of infectious inflammation. Identification of the isolated microorganisms was carried out using the MALDI ToF mass spectrometry method, followed by determination of antibiotic resistance. Empirical antibiotic therapy was prescribed upon admission of the patient to the ICU. Patients were switched to etiotropic antibacterial therapy after 48 hours, taking into account the results of a microbiological study. Determination of basal metabolic rate was carried out using the method of indirect calorimetry (CCM Express, Medical Graphics) with the calculation of basal metabolism, respiratory coefficient, absolute and relative amount of macronutrients. The calculation of the protein was made on the basis of the nitrogen level of the daily urine urea. Logistic analysis (ROC analysis) revealed that the antibacterial therapy strategy used, age, gender of patients, tinctorial properties of microorganisms isolated from patients, do not affect the nearest prognosis of the disease. On the contrary, SOFA score, the concentration of procalcitonin in the blood, and such parameters of the metabolic status as the need for kilocalories per kilogram of actual body weight and the percentage of protein calories significantly affect the nearest prognosis of the disease. The percentage of calories derived from protein metabolism, in the main exchange has a high reliable predictive value. The results of the study confirm the importance of adequate nutritional therapy in the treatment of patients with infectious inflammatory syndrome, including the calculation and correction of protein loss and total daily calorie., Competing Interests: The authors declare no conflict of interest.

The aim of our research was to evaluate the structure and the determination of the phenotypes of antibiotic resistance of microflora isolated from patients' blood in a multidisciplinary hospital during the period from 2013 to 2017. The material was taken into BacT / ALERT bottles containing nutrient media, followed by incubation of blood. In case of a positive result, the material from the vials was dispersed into dense nutrient media. Species identification was carried out using commercial biochemical API test systems and MALDITOF mass spectrometry. The antibiotic resistance of the isolated microorganisms was evaluated by a classical disc-diffusion method. From 2013 to 2017, 3504 blood tests were performed, of which 16.8% were positive. Of the isolated strains, 69.6% were Gram-positive, 27% were Gram-negative, and 3.4% were fungi. The structure of Gram-positive bacteria included Staphylococcus spp - 71.46%, Enterococcus spp. - 21.22% and Streptococcus spp - 7.32%. Staphylococcus aureus (47,8%) prevailed among staphylococci (in 62.14% were methicillin-resistant) and coagulase-negative staphylococci. Among the genus Enterococcus spp, Enterococcus faecalis prevailed (27% resistant to macrolides, 14% to fluoroquinolones) and Enterococcus faecium (69% resistant to penicillins, fluoroquinolones, macrolides). Streptococcus pneumoniae, Streptococcus pyogenes and streptococci from the group of alpha-greening were isolated from streptococci. Clinically significant types of streptococci in 33.3% were resistant to macrolides and fluoroquinolones. In the structure of gram-negative bacteria, Enterobacteriaceae prevailed - 71.07% (Klebsiella pneumoniae, E. coli); the proportion of non-fermenting Gram-negative bacteria (NFGOB) was 28.93%. Most Gram-negative bacteria were producers of extended-spectrum beta-lactamases (BLBRs). In NFGOB structure allocated Acinetobacter baumanii - 56,5% (81% polyresistant), Pseudomonas aeruginosa - 30,4% (50% - Carbapenemase Producing Organisms), Stenotrophomonas maltophilia - 10,9%. Thus, microbiological research in septic blood conditions is an integral part of the diagnostic search, selection of etiotropic therapy and monitoring of its effectiveness., Competing Interests: The authors declare no conflict of interest.

The mycobacterioses as a group of diseases conditioned by non-tuberculosis mycobacteria, acquire even greater significance for patients from various risk groups. The patients with cystic fibrosis along with patients with other genetic diseases, consist risk group of infection with non-tuberculosis mycobacteria. The diagnostic of mycobacterioses in patients with cystic fibrosis has a number of peculiarities both at the stage of processing clinical material and the stage of identification of separated microorganisms. The review presents modern data about possibilities of laboratory diagnostic of with regard to characteristics of epidemiology, risk factors, contamination screening, material decontamination, methods of cultivation and identification of non-tuberculosis mycobacteria in patients with cystic fibrosis. The data is presented concerning increasing of morbidity of mycobacterioses up to 6-13% among patients with cystic fibrosis in developed countries. The low level of prevalence of mycobacterioses among patients with cystic fibrosis in the Russian Federation is demonstrated. The risk factors of development of mycobacterioses from point of view of contamination with various microorganisms, particularly with fungi of species Aspergillus are described. The technique of two-stage decontamination of phlegm and possible limitations of its cultivation in automated systems and possibilities of using 1% solution of chlorhexidine and sodium dodecyl sulfate for decontamination are described. Besides standard techniques, a technique of separation of mycobacteria is presented based on inoculation of material on medium for selective separation of Burkholderia cepacia complex. The possibilities of identification of mycobacteria using MALDIToF mass-spectrometry. The review was based on sources from such international and national data bases as Scopus, Web of Science, RINC., Competing Interests: The authors declare no conflict of interest.