Представлены результаты исследования микробного пейзажа содержимого нижних дыхательных путей при внебольничной пневмонии, ассоциированной с COVID-19. Показано, что в структуре бактерий выделенных от пациентов с диагнозом внебольничная пневмония превалируют грамположительные кокки, преимущественно бактерии рода Streptococcus. По частоте обнаружения бактерий семейства Enterobacteriaceae и неферментирующих грамотрицательных бактерий в сравниваемых группах (SARS-COV-2 «обнаружен» / «не обнаружен») статистически значимых различий не отмечено.
Introduction. is to The analysis of the genetic relatedness of isolates aiming to find the source of infection is an important task of nosocomial infection control. The most common causative agent of healthcare-associated infections is Acinetobacter baumannii.Objective. To evaluate the results of whole genome sequencing of A. baumannii bacteria isolated from clinical samples of patients undergoing inpatient treatment in the northern territories of the Tyumen region.Materials and methods. Nine isolates of A. baumannii from the clinical material of patients were studied. Bacterial cultures were identified by mass spectrometry. Whole genome sequencing, multilocus sequence typing and search for markers of antibiotic resistance were performed.Results. The studied strains belonged to sequence types ST2 and ST187, and to the international clonal complex CC2. All A. baumannii isolates were found to have beta-lactamase genes, as well as genes for resistance to aminoglycosides, to the MLS group of antibiotics, and to tetracyclines. The presence of a cluster of genes associated with virulence was detected: those responsible for the synthesis of acinetobactin and iron binding, surface antigen 1 and porin.Conclusion. Based on data of a single nucleotide polymorphism (SNP) analysis, A. baumannii isolates from the clinical material of patients of healthcare institution #1 belong mainly to one bacterial strain. Isolates of A. baumannii from the clinical material of patients of healthcare institution #2 are closely related. The ability to distinguish clinical isolates of A. baumannii at the level of several SNPs per genome will improve the identification of the source of infection, and whole genome sequencing data can contribute to the rational prescription of antibiotic therapy and the correction of disinfection and antiseptic measures.
Abstract. Multidrug-resistant K. pneumoniae bacterial strains producing extended range of beta-lactamases or carbapenemases are of serious clinical concern. The aim of the study was to determine the resistance factors of K. pneumoniae strains isolated from the lower respiratory tract of patients diagnosed with community-acquired pneumonia during the COVID-19 pandemic. Materials and methods. The study of resistance to antimicrobial drugs included 138 strains of K. pneumoniae isolated from the sputum of patients treated in infectious diseases monohospitals in the city of Tyumen and the Tyumen region within the period from May 2020 to June 2021. Among the strains examined, 51.4% of them were isolated from SARS-CoV-2 positive patients. The presence of resistance genes was determined by PCR in 71 strains of K. pneumoniae (34 strains from COVID-19-positive and 37 strains from COVID-19-negative patients). Identification of isolated bacterial strains was carried out according to the protein spectra by using a desktop time-of-flight mass spectrometer with matrix laser desorption MALDI-TOF MS (Bruker, Germany). The belonging of the strains to the hypermucoid phenotype was determined using the string test. Sensitivity to antimicrobial drugs was assessed in the disk diffusion method on Muller-Hinton medium. The sensitivity of culture strains to bacteriophage preparations was determined by the drop method (spot-test). In the study, we used “Polyvalent Sextaphage Pyobacteriophage” and “Purified Polyvalent Klebsiella Bacteriophage”, JSC NPO Microgen, Russia. Detection of resistance genes to beta-lactam antibiotics by real-time PCR was carried out using the BakRezista kit (OOO DNA-technology, Russia). The results of the study evidence that K. pneumoniae bacteria isolated from COVID-19-positive and COVID-19-negative patients diagnosed with community-acquired pneumonia displayed a high resistance to antimicrobial drugs and commercial phage-containing drugs. Resistance of K. pneumoniae strains was recorded from 50% (to aminoglycosides and carbapenems) to 90% (to inhibitor-protected penicillins). Sensitivity to bacteriophages was noted on average in no more than 20% of strains. It is important to emphasize that strains isolated from COVID-19-positive patients more often showed a hypermucoid phenotype, suggesting a high bacterial virulence, and also showed greater resistance to all groups of antibacterial drugs examined in the study, which is confirmed by the presence of resistance genes of the ESBL group and carbapenemase. The results of the study suggest that the high level of resistance of K. pneumoniae strains isolated from COVID-19-positive patients is associated with immunosuppression provoked by the SARS-CoV-2 virus, which contributes to their colonization by more virulent strains.
Представлены результаты исследований антибиотикорезистентности штаммов, выделенных от пациентов с диагнозом внебольничная пневмония в период пандемии новой короновирусной инфекции, вызванной SARS-COV-2. Проведенный анализ чувствительности бактерий к антимикробным препаратам показал, что наибольшие уровни резистентности выявлены у штаммов Acinetobacter baumannii, Enterococcus faecium и Klebsiella pneumoniae. Статистически значимых различий по резистентности изолятов к АПМ в зависимости от наличия SARS-CoV-2 не отмечено. При этом фиксируются тенденции более высокого уровня резистентности штаммов Klebsiella pneumoniae, и в целом представителей семейства Enterobacteriaceae, Pseudomonas spp., Haemophilus spp. и Staphylococcus spp., изолированных от пациентов с неподтвержденным наличием SARS-CoV-2.
Цель - изучение видового состава бактерий рода Streptococcus, выделенных из мокроты и промывных вод бронхов у пациентов с диагнозом внебольничная пневмония, в том числе ассоциированной с COVID-19, и определение их спектра резистентности к антимикробным препаратам. Материалы и методы. Проанализирован видовой состав бактерий рода Streptococcus, изолированных из отделяемого нижних дыхательных путей от 308 пациентов с диагнозом внебольничная пневмония. Результаты. В структуре видов Streptococcus spp. преобладает S. mitis в 46,1% случаев у ковидпозитивных пациентов и 33,3% у ковиднегативных. Бактерии рода S. pneumoniae бактериологическим методом изолированы в 3,8±2,0% проб, методом ПЦР в 33±5,3% у ковидпозитивных пациентов. У пациентов с неподтвержденным SARS-CoV-2 S. pneumoniae выделен в 6,1±4,2% случаев бактериологическим методом и ПЦР методом в 31,9±8,1% проб биологического материала. Более 65% штаммов бактерий рода Streptococcus проявляли резистентность к ампициллину, вне зависимости от статуса ковидпринадлежности.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.