Characteristics of Stenotrophomonas maltophilia isolates from cystic fibrosis patients in Russia.

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.

Genome features and antibiotic resistance of Pseudomonas aeruginosa strains isolated in patients with cystic fibrosis in the Russian Federation.

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.

[Structure of microorganisms isolated from bronhoalveolar lavage from patients in the department of reanimation and intensive therapy.] / Структура микроорганизмов, Ð²Ñ‹Ð´ÐµÐ»ÐµÐ½Ð½Ñ‹Ñ Ð¸Ð· Ð±Ñ€Ð¾Ð½Ñ Ð¾Ð°Ð»ÑŒÐ²ÐµÐ¾Ð»ÑÑ€Ð½Ð¾Ð³Ð¾ лаважа от пациентов отделения реанимации и интенсивной терапии.

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.

[Mycobacterium abscessus complex representatives in patients with bronchopulmonary pathology: prevalence, peculiarities of cultivation and identification.]

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%.

[The laboratory diagnostic in patients with mucoviscidosis: A review.]

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.

[Applicability of antibacterial agents in chronic tonsillitis treatment]. / Vozmozhnosti primeneniia antibakterial'nykh sredstv pri khronicheskom tonzillite.

The purpose of the present study was to evaluate the effectiveness of nitrofuranes applied for the treatment of chronic tonsillitis. A total of 92 subjects divided into three cohorts were involved in this study. Cohort 1 included 43 patients presenting with decompensated chronic tonsillitis and having pathogens in palatine tonsil lacunae. Cohort 2 was comprised of 13 patients with compensated chronic tonsillitis having pathogenic microflora of the same localization, while Cohort 3 was composed of 36 patients resembling those of cohort 1 in terms of clinical presentation, pathogen composition, and microbial spectrum. While the patients of cohort 1 and cohort 2 were treated by rinsing their tonsil lacunae with a furasol solution as a single-drug therapeutic procedure, those comprising Cohort 3 underwent treatment with furacilinum for the same purpose. The results of the study give evidence of the important advantages of furasol therapy over other modalities for the conservative treatment of chronic tonsillitis.