Antimicrobial Resistance

New mutations in genes associated with cefiderocol resistance in a clinical isolate of Pseudomonas aeruginosa

Objective. To assess the effects of chromosomal mutations on emergence of cefiderocol resistance among Pseudomonas aeruginosa clinical isolates. Materials and Methods. Study design purported to compare the characteristics of phenotypic antibiotic resistance and chromosomal mutations of P. aeruginosa strains of a common origin possessing different resistance levels to cefiderocol. Two P. aeruginosa isolates from the sputum of a patient with cystic fibrosis who had not previously received cefiderocol were analyzed.

Evaluation of the effectiveness of antimicrobial stewardship program: results from a ten-year study in a multidisciplinary hospital

Objective. To evaluate the results of the implementation of antimicrobial stewardship (AMS) program in a multidisciplinary hospital. Materials and Methods. A retrospective intervention study was performed in the 600-bed multidisciplinary hospital of the Pirogov National Medical and Surgical Center (Moscow, Russia). The study included a number of sequential interventions, aimed at improving the prevention, diagnosis and treatment of infections, with an assessment of the following indicators dynamics: the structure of microorganisms isolated in the hospital, the level of resistance to antimicrobial drugs (AMD) among the pathogens of the ESKAPE group, the structure of prescribed AMD, as well as an assessment of clinical and economic consequences of antimicrobial resistance changes.

Antimicrobial resistance-associated mutations in chromosomal genes of ESKAPE pathogens

The worldwide successful expansion of ESKAPE pathogens is largely due to their ability to rapidly acquire high antimicrobial resistance levels. The bacterial resistome includes (1) plasmid-encoded genes acquired as a result of horizontal gene …

Systemic analysis of the AST results in medical organizations of the Russian Feder ation

Objective. To analyse aggregated AST results for key microorganisms collected through the 2022 reports of chief specialists in clinical microbiology and antimicrobial resistance. Materials and Methods. The study included an analysis of the interpretation criteria used in the laboratories and an evaluation of the AST reports. Data were obtained from the clinical microbiology and antimicrobial resistance annual reporting system. Reports were analyzed using EUCAST guidelines for expected resistance phenotypes and expected susceptible phenotypes.

AMRexpert – online platform for interpretation, verification and validation of antimicrobial susceptibility testing

Objective. To review the key principles and functionality of AMRexpert online platform. Materials and Methods. The information part of the platform is comprised of rules based on the EUCAST recommendations and various standards for interpreting the results of antimicrobial susceptibility testing (EUCAST, CLSI versions 2020-2022). The technical part of the platform was developed using C# programming language, Angular and Bootstrap frameworks. AST results of Serratia marcescens, Pseudomonas aeruginosa, Staphylococcus saprophyticus, Enterococcus faecium specific isolates were analyzed for practical testing of the platform using EUCAST v.

Epidemiology and impact of colonization by multidrug-resistant Gram-negative bacteria on bloodstream infections in early phase of allogeneic hematopoietic stem cell transplantation

Objective. To study epidemiology and impact of colonization by multidrug-resistant Gram-negative bacteria (MDRGNB) on bloodstream infections (BSI) during allogeneic hematopoietic stem cell transplantation (allo-HSCT). Materials and Methods. The retrospective study included 288 patients received the first allo-HSCT between 2018 and 2019. The median age was 32 (18–66) years, male – 53% (n = 152). The majority of patients had acute leukemia – 62% (n = 178) and received transplant from matched unrelated – 42% (n = 120) or haploidentical donor – 26% (n = 75).

Prevalence of the A2058G mutation in 23S rRNA gene, which determines Treponema pallidum macrolide resistance in Russian population

Objective. To investigate prevalence of the A2058G mutation in the Russian population of T. pallidum and its association with molecular subtypes. Materials and Methods. We analyzed DNA isolated from 325 samples of clinical material obtained from patients of dermatovenereological treatment and prophylactic institutions in 6 federal districts of the Russia in the period from 2014 to 2021. Patients were diagnosed with primary syphilis of the genital organs, primary syphilis of other sites, or secondary syphilis of the skin and mucous membranes.

Analysis of the genes encoding the MBL-fold metallohydrolase superfamily proteins of the Pseudomonas putida BS3701 petroleum component-degrading strain

Objective. To determine whether the genes whose products are annotated as «MBL-fold metallohydrolase superfamily» are related to the proteins of the metallo-β-lactamase group. Materials and Methods. Sequences of the 7 genes annotated as «MBL-fold metallohydrolase superfamily» were analyzed using the following resources: ClustalW, IQ-TREE, iTOL. Selection of the oligonucleotides for real-time PCR was performed using the Primer-BLAST resource. The level of gene expression was assessed using real-time PCR. MIC and MBC measuring was performed using cefepime and meropenem.

The prevalence and characterization of ESBL-producing strains of Salmonella enterica circulating in the territory of the Russian Federation (2016–2020)

Objective. To analyze frequency and identify genetic determinants of resistance of non-typhoid Salmonella (NTS) producing extended-spectrum β-lactamase (ESBL) isolated in the Russian Federation over the period 2016 to 2020. Materials and Methods. Salmonella isolates, suspected to ESBL production, were collected by the All-Russia Reference Center of Salmonellosis during the national Salmonellosis surveillance program. Phenotypic resistance was determined by the broth microdilution method using G-I and G-II Mikrolatest®SensiLaTest MIC plates and by the double-disk synergy test.

Distribution of antimicrobial resistance among clinical and food Listeria monocytogenes isolated in Moscow in 2019–2021

Objective. To determine the current state-of-art of acquired resistance to antimicrobial drugs among L. monocytogenes strains associated with listeriosis in humans and food contamination in Moscow. Materials and Methods. We used 39 L. monocytogenes strains isolated in Moscow in 2019–2021 from clinical material (n = 24) and food (n = 15). Resistance to 12 antibiotics of the first and second lines of defense was studied using disk-diffusion method. The parameters recommended for L.