Methicillin-resistant Staphylococcus aureus (MRSA) is a common multidrug-resistant (MDR) pathogen. We herein discussed MRSA and its infections in Krasnoyarsk, Siberian Russia between 2007 and 2011. The incidence of MRSA in 3,662 subjects was 22.0% and 2.9% for healthcare- and community-associated MRSA (HA- and CA-MRSA), respectively. The 15-day mortality rates for MRSA hospital- and community-acquired pneumonia (HAP and CAP) were 6.5% and 50%, respectively. MRSA CAP cases included pediatric deaths; of the MRSA pneumonia episodes available, ≥27.3% were associated with bacteremia. Most cases of HA-MRSA examined exhibited ST239/spa3(t037)/SCCmecIII.1.1.2 (designated as ST239Kras), while all CA-MRSA cases examined were ST8/spa1(t008)/SCCmecIV.3.1.1(IVc) (designated as ST8Kras). ST239Kras and ST8Kras strongly expressed cytolytic peptide (phenol-soluble modulin α, PSMα; and δ-hemolysin, Hld) genes, similar to CA-MRSA. ST239Kras pneumonia may have been attributed to a unique set of multiple virulence factors (MVFs): toxic shock syndrome toxin-1 (TSST-1), elevated PSMα/Hld expression, α-hemolysin, the staphylococcal enterotoxin SEK/SEQ, the immune evasion factor SCIN/SAK, and collagen adhesin. Regarding ST8Kras, SEA was included in MVFs, some of which were common to ST239Kras. The ST239Kras (strain OC3) genome contained: a completely unique phage, φSa7-like (W), with no att repetition; S. aureus pathogenicity island SaPI2R, the first TSST-1 gene-positive (tst +) SaPI in the ST239 lineage; and a super copy of IS256 (≥22 copies/genome). ST239Kras carried the Brazilian SCCmecIII.1.1.2 and United Kingdom-type tst. ST239Kras and ST8Kras were MDR, with the same levofloxacin resistance mutations; small, but transmissible chloramphenicol resistance plasmids spread widely enough to not be ignored. These results suggest that novel MDR and MVF+ HA- and CA-MRSA (ST239Kras and ST8Kras) emerged in Siberian Russia (Krasnoyarsk) associated with fatal pneumonia, and also with ST239Kras, a new (Siberian Russian) clade of the ST239 lineage, which was created through stepwise evolution during its potential transmission route of Brazil-Europe-Russia/Krasnoyarsk, thereby selective advantages from unique MVFs and the MDR.
Purulent inflammatory diseases of various types and etiology comprise major causes of death among the HIV-infected individuals. The purpose of this work was to determine a variety of communityacquired pathogens causing pneumonia, their antibiotic resistance profiles, and dependence on the CD4 lymphocyte levels, as well as identification of methicillin-resistant Staphylococcus aureus species and their molecular genetic characteristics in HIV-infected patients from the Krasnoyarsk City. Over the period of 2012 to 2016, we have examined 152 HIV-infected patients at the Clinical Pulmonology Department with a verified diagnosis of community-acquired pneumonia. Sputum specimens, bronchoalveolar lavage, pleural fluid, washings, pleural pus, as well as nasal and pharyngeal smears were studied for microflora, and blood tests for sterility were performed in these patients, by means of bacteriological techniques. Antibiotic sensitivity was determined by the disc diffusion method; drug sensitivity of staphylococci was performed by screening, PCR technique, serial dilution in semi-solid medium, according to the CLSI and EUCAST recommendations. PCR, M-PCR, and gene sequencing were applied for genotyping and determination of their genetic features. The results were processed with WHONET digital program (WHO). The significance level was p < 0.05. During the entire study period, the yeast-like fungi of Candida genus (30.4 and 35.6%) were consistently isolated from HIV-infected patients. These microorganisms were isolated in a pure cultures at etiologically significant amounts from one-third of the HIV-infected cohort. At the same time, they formed active associations, mostly with Enterobacteriaceae family members. At the same time, Candida fungi were most frequently detected in the lower respiratory tract of those HIV-infected persons who showed severe immunodeficiency (CD4 cell levels < 200 cells/µl). We have also isolated non-fermenting Gram-negative bacteria (12.9%), staphylococci (8.9%), and Enterobacteriaceae (4.4%). The microorganisms were characterized by polyresistance to antimicrobial agents. The MRSA clone circulating in the HIV-infected cohort was characterized as ST239/spa3(t037) /agr1/SCCmecIII.1.1.2 (IIIA)/coaIV/tst+ with high virulence and multiresistance levels. Hence, we have found a number of poly-resistant microorganisms playing a role for development of community-acquired pneumonia in HIV-infected patients, i.e., Candida spp, Gram-negative microorganisms, MRSA, often presenting a component of microbial associations. Candida fungi were detected most often in the HIV-infected individuals with severe immunodeficiency, at the CD4 level of < 200 cells/µl. High detection frequency of such microflora requires some modifications of antimicrobial therapy in HIV-infected subjects affected by the community-acquired pneumonia.
Изучена роль метициллинрезистентных S. aureus и их молекулярно-генетические особенности в развитии инфекций кожи и мягких тканей (абсцессов, флегмон) у ВИЧ-инфицированных. Материал для исследованиягнойное отделяемое, биоптат. Посев материала осуществляли на комплекс питательных сред по методу Gould, чувствительность определяли стандартными методами дисковой диффузии, скрининга и E-тест. Для генетических исследований MRSA получали суточную культуру и выделяли ДНК. Для генотипирования штаммов (SCCmec, spa; ST, agr) и определения генов вирулентности (42 гена) Summary HIV-infected people are at increased risk of contracting MRSA. The role of MRSA and their molecular genetic features in the development of infections of the skin and soft tissues (abscesses, cellulitis) in HIV-infected individuals were studied. The material for the study-purulent discharge, biopsy. Sowing material was carried out on a complex of culture media. Antibiotic resistance in microorganisms was determined by methods in accordance with international recommendations. For genetic studies, MRSA received a daily culture and DNA was isolated. For the genotyping of strains (SCCmec, spa; ST, agr) and the determination of virulence genes (42 genes),
Резюме. Гнойно-некротические осложнения у больных с синдромом диабетической стопы являются одной из главных причин ампутаций и инвалидизации и даже гибели пациентов. Целью данной работы явилось изучение роли MRSA и их молекулярно-генетических особенностей, а также антибиотикорезистентности в развитии гнойно-некротических форм синдрома диабетической стопы пациентов г. Красноярска за период 2010-2016 гг. Исследована в динамике микрофлора гнойно-некротических осложнений у 240 пациентов с синдромом диабетической стопы, ее антибиотикочувствительность, а также молекулярно-генетические особенности метициллинрезистентных Staphylococcus aureus. Для изучения микрофлоры гнойных осложнений использован бактериологический метод. Антибиотикочувствительность определяли диско-диффузионным методом; чувствительность стафилококков к антибиотикам проводили методом скрининга, ПЦР, методом серийных разведений в плотной среде в соответствии с международными рекомендациями СLSI, EUCAST. Для генотипирования и определения молекулярно-генетических особенностей-ПЦР, М-ПЦР, секвенирование. Обработку результатов проводили с использованием компьютерной программы WHONET (ВОЗ). Уровень значимости p < 0,05. Микрофлора гнойно-некротических форм синдрома диабетической стопы представлена грамотрицательными микроорганизмами-на долю представителей семейства Enterobacteriaceae приходилось 34,4%, неферментирующих грамотрицательных бактерий-19,1%; грамположительными
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.
customersupport@researchsolutions.com
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.