Drug resistance and pathogenicity of S. aureus isolated from patients
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The previous use of fresh porcine xenografts at the Prague Burn Centre had raised concerns over the transmission of zoonotic pathogens. This study examines the risk of zoonotic Staphylococcus aureus colonisation of burn patients from fresh porcine skin xenografts. Samples were collected from the nares, skin and perineum of commercial pigs (n=101) and were screened for methicillin sensitive S. aureus (MSSA) and resistant S. aureus (MRSA). The efficacy of the antibiotic wash used in decontamination of the pigskin was tested against planktonic- and biofilm-grown isolates. The spa type of each isolate was also confirmed. All pig swabs were negative for MRSA but 86% positive for MSSA. All planktonic-grown isolates of MSSA were sensitive to chloramphenicol and nitrofurantoin and 44% of isolates were resistant to streptomycin. Isolates grown as biofilm exhibited higher rates of antimicrobial resistance. Sequence analysis revealed three distinct spa types of the MRSA ST398 clonal type. This finding demonstrates the existence of a MSSA reservoir containing spa types resembling those of well-known MRSA strains. These MSSA exhibit resistance to antibiotics used for decontamination of the pigskin prior to xenograft. Amended use of procurement could allow the use of fresh pigskin xenografts to be reinstated.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální léková rezistence MeSH
- biologické krytí mikrobiologie MeSH
- chloramfenikol farmakologie MeSH
- kůže mikrobiologie MeSH
- lidé MeSH
- methicilin rezistentní Staphylococcus aureus účinky léků genetika izolace a purifikace MeSH
- mikrobiální testy citlivosti MeSH
- nitrofurantoin farmakologie MeSH
- nos mikrobiologie MeSH
- perineum mikrobiologie MeSH
- popálení terapie MeSH
- prasata mikrobiologie MeSH
- Staphylococcus aureus účinky léků genetika izolace a purifikace MeSH
- streptomycin farmakologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Methicillin-resistant Staphylococcus aureus (MRSA) is the causal agent of multiple nosocomial infections worldwide, including catheter-associated bacteremia in hemodialysis patients. The purposes of this work were to genetically characterize a group of MRSA isolates from catheter-related infections of ambulatory Mexican hemodialysis patients and to determine whether the strains are the same as those carried by the patients in their anterior nares. Sixteen pairs of MRSA isolates from the catheter (cat) and anterior nares (N) of hemodialysis patients were compared using pulsed-field gel electrophoresis (PFGE), PCR detection of adhesion genes and other virulence markers, and an antibiogram. Three pairs of N/cat MRSA isolates (18.7 %) with identical resistograms also showed the same combination of PCR-detected markers and PFGE pattern; one additional pair showed only an identical electrophoretic PFGE pattern. Of the MRSA isolates, 75 % (n = 24) were resistant to ≥ 7 antibiotics, 4 isolates were resistant to 11 antibiotics, and 7 isolates were resistant to the 12 antibiotics tested. The most frequent virulence marker combination found was spa, clfA, clfB, cna, bbp, ebps, map/eap, sdrC, sdrD, sdrE, ica, agr (65.6 %, n = 21). The SCCmec alleles of the 32 MRSA isolates were IV (n = 20), I (n = 7), II (n = 4), and V (n = 1), and no SCCmec type III MRSA was found. The genotypic characterization of the MRSA isolates studied in this work will contribute to a better understanding of the virulence gene makeup of catheter-colonizing S. aureus strains and will help to lower the infection risk in these patients.
- MeSH
- dialýza ledvin MeSH
- DNA bakterií chemie genetika MeSH
- dospělí MeSH
- faktory virulence genetika MeSH
- katétry mikrobiologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- methicilin rezistentní Staphylococcus aureus genetika izolace a purifikace MeSH
- mikrobiální testy citlivosti MeSH
- polymerázová řetězová reakce MeSH
- pulzní gelová elektroforéza MeSH
- rozdělení chí kvadrát MeSH
- senioři MeSH
- stafylokokové infekce mikrobiologie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Mexiko MeSH
Staphylococcus aureus is one of the most frequent pathogens infecting the respiratory tract of patients with cystic fibrosis (CF). This study was the first to examine S. aureus isolates from CF patients in the Czech Republic. Among 100 S. aureus isolates from 92 of 107 observed patients, we found a high prevalence of resistance to macrolide-lincosamide-streptogramin B (MLS(B)) antibiotics (56%). More than half of the resistant strains (29 of 56) carried a mutation in the MLS(B) target site. The emergence of MLS(B) resistance and mutations conferring resistance to MLS(B) antibiotics was associated with azithromycin treatment (p=0.000000184 and p=0.000681, respectively). Methicillin resistance was only detected in 3% of isolates and the rate of resistance to other antibiotics did not exceed 12%. The prevalence of small-colony variant (SCV) strains was relatively low (9%) and eight of nine isolates with the SCV phenotype were thymidine dependent. The study population of S. aureus was heterogeneous in structure and both the most prevalent community-associated and hospital-acquired clonal lineages were represented. Of the virulence genes, enterotoxin genes seg (n=52), sei (n=49), and sec (n=16) were the most frequently detected among the isolates. The PVL genes (lukS-PV and lukF-PV) have not been revealed in any of the isolates.
- MeSH
- antibakteriální látky farmakologie terapeutické užití MeSH
- azithromycin terapeutické užití MeSH
- bakteriální léková rezistence genetika MeSH
- cystická fibróza mikrobiologie MeSH
- dlouhodobá péče MeSH
- infekce spojené se zdravotní péčí mikrobiologie MeSH
- lidé MeSH
- methicilin rezistentní Staphylococcus aureus účinky léků MeSH
- mikrobiální testy citlivosti MeSH
- mutace genetika MeSH
- ribozomy genetika MeSH
- stafylokokové infekce farmakoterapie mikrobiologie MeSH
- Staphylococcus aureus účinky léků genetika MeSH
- thymidin genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
Autoři popisují stav a vlastnosti kožní mikroflóry u 51 pacientů s akné v závislosti na léčbě vakcínou nebo antibiotiky. Dále ověřují genetickou shodu u fenotypově stejných izolátů získaných od jednoho pacienta při opakovaných odběrech. U druhu Staphylococcus aureus pak stanovují vybrané faktory virulence.Práce potvrdila spoluúčast stafylokoků a propionibakterií v etiopatogenezi akné, dokumentovala i jejich statisticky nevýznamné ovlivnění oběma způsoby léčby. Testy citlivosti prokázaly jen nízkou rezistenci Propionibacterium acnes na klindamycin (6,7 %), která však byla vyšší u druhu Staphylococcus epidermidis (na erytromycin 73,4 %, klindamycin 62,6 %). V průběhu sledování nebyly prokázány její signifikantní změny. Fenotypově shodné kmeny koaguláza-negativních stafylokoků byly nalezeny u 12 pacientů. Analýzou elektroforetických profilů jejich DNA byla zjištěna genetická shoda u 6 (50 %) klinických případů. Detekce faktorů virulence u Staphylococcus aureus prokázala přítomnost genu pro tvorbu Pantonova-Valentinova leukocidinu u třech kmenů. Geny pro enterotoxin A a TSST-1 nebyly nalezeny.
Authors characterized skin microflora in 51 patients with acne after treatment either with vaccine or antibiotics. They also verified genetic homology of phenotypically identical isolates repetitively taken from the same patient and determined selected virulence factors in Staphylococcus aureus species. Study confirmed participation of staphylococci and propionibacteriae in etiopathogenesis of acne and documented statistically not significant influence of both treatment modalities on the above mentioned pathogens. Sensitivity tests confirmed only low resistance of Propionibacterium acnes to klindamycin (6.7%) and higher resistance of Staphylococcus epidermidis species (73.4% to erythromycin and 62.2% to klindamycin). Significant resistance changes were not demonstrated during study. Identical phenotype of coagulase negative staphylococci strains was found in 12 patients. Electrophoretic DNA profile analysis revealed genetic homology in 6 (50%) cases. Virulence factors detection demondetekostrated presence of gene for Panton-Valentine leukocidine synthesis in 3 Staphylococcus aureus strains. No enterotoxin A and TSST-1 genes were found.
- MeSH
- acne vulgaris farmakoterapie mikrobiologie MeSH
- antibakteriální látky terapeutické užití MeSH
- bakteriální léková rezistence imunologie účinky léků MeSH
- faktory virulence MeSH
- finanční podpora výzkumu jako téma MeSH
- lidé MeSH
- Propionibacterium acnes účinky léků MeSH
- Staphylococcus aureus účinky léků MeSH
- Staphylococcus epidermidis účinky léků MeSH
- statistika jako téma MeSH
- vakcíny terapeutické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- srovnávací studie MeSH
Bacterial variants of Staphylococcus aureus called small colony variants (SCVs) originate by mutations in metabolic genes, resulting in emergence of auxotrophic bacterial subpopulations. These variants are not particularly virulent but are able to persist viable inside host cells. SCVs show their characteristic auxotrophic growth deficiency and depressed α-cytotoxin activity. Environmental pressure such as antibiotics, select for isogenic SCV cells that are frequently found coexisting with their parent wild-type strains in a mixed bacterial culture. SCV strains often grow on blood agar as non-pigmented or pinpoint pigmented colonies and their key biochemical tests are often non-reactive. Their altered metabolism or auxotrophism can result in long generation time and thus SCV phenotype, more often than not SCV can be overgrown by their wild-type counterparts and other competitive respiratory flora. This could affect laboratory detection. Thus, molecular methods, such as 16S rRNA partial sequencing or amplification of species-specific DNA targets (e.g. coagulase, nuclease) directly from clinical material or isolated bacterial colonies, become the method of choice. Patients at risk of infection by S. aureus SCVs include cystic fibrosis patients (CF), patients with skin and foreign-body related infections and osteomyelitis, as they suffer from chronic staphylococcal infections and are subject to long-term antibiotic therapy. Molecular evidence of SCV development has not been found except for some random mutations of the thymidylate synthase gene (thyA) described in SCV S. aureus strains of CF patients. These variants are able to bypass the antibiotic effect of folic acid antagonists such as sulfonamides and trimethoprim. Resistance to gentamicin and aminoglycosides in the hemin or menadione auxotrophic SCVs was hypothesized as being due to decreased influx of the drugs into cells as a result of decreased ATP production and decreased electrochemical gradient on cell membranes.
- MeSH
- faktory virulence metabolismus MeSH
- financování organizované MeSH
- genetická variace MeSH
- lidé MeSH
- metabolické sítě a dráhy genetika MeSH
- mutace MeSH
- stafylokokové infekce mikrobiologie MeSH
- Staphylococcus aureus genetika metabolismus patogenita růst a vývoj MeSH
- virulence MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
Medical students are exposed to the hospital environment and patients during their studies, increasing the risk of exposure to virulent and antibiotic-resistant isolates of Staphylococcus aureus. The aim of the study is to determine the prevalence of Staphylococcus aureus among medical students who have varying levels of exposure to the hospital environment to provide valuable insights into the risk of colonization and transmission. Nasal swabs and fingerprints were obtained and cultured on a selective medium for staphylococci. The obtained isolates were confirmed as methicillin-sensitive S. aureus (MSSA) or methicillin-resistant (MRSA) using PCR. Antibiotic resistance, the presence of virulence genes including enterotoxin encoding genes, and spa typing were performed. Among pre-clinical students, MSSA was detected on the nose in 45.2% and on the fingerprints in 10.6% of the participants. Among clinical students, MSSA was detected on the nose in 42.0% and on the fingerprints in 25.4%. Only one MRSA isolate was obtained. Genes seg and sei were the most frequently detected in both student groups, with their presence in over 40% of isolates among clinical students. The eta and etb genes were mainly detected from the nose in both student groups. In pre-clinical students, S. aureus carrying eta gene occurred in 6.4% and etb in 8.5%. In clinical students, the occurrence was 5.1% for eta and 8.5% for etb. The tst gene was identified only in the nose and fingerprints of the clinical student group. The most frequently observed resistance was to clindamycin and erythromycin. In total 58 different spa types were identified. High rates of asymptomatic MSSA carriage were observed in both groups of medical students. Detected MSSA strains showed a high degree of genetic variability, with a number of them carrying the virulence and antibiotic resistance genes. Although students do not exhibit increased risk to their patient's, increased hygiene is required in asymptomatic carriage personnel. The overall prevalence of MRSA was low, with a minimal risk of spread.
- MeSH
- antibakteriální látky farmakologie MeSH
- dospělí MeSH
- faktory virulence * genetika MeSH
- lidé MeSH
- methicilin rezistentní Staphylococcus aureus genetika izolace a purifikace účinky léků klasifikace MeSH
- mikrobiální testy citlivosti MeSH
- mladý dospělý MeSH
- přenašečství * mikrobiologie epidemiologie MeSH
- prevalence MeSH
- stafylokokové infekce * mikrobiologie epidemiologie MeSH
- Staphylococcus aureus * genetika izolace a purifikace účinky léků klasifikace MeSH
- studenti lékařství * MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
A rather fast and complicated progression of an infection caused by some strains of Staphylococcus aureus could be associated with the expression and co-action of virulence factor complexes in these strains. This study screened the antibiotic susceptibility and prevalence of virulence markers in isolates of meticillin-resistant S. aureus (MRSA) obtained from patients hospitalized at the University Hospital in Olomouc, Czech Republic. A total of 100 isolates was screened for 13 genes encoding extracellular virulence determinants (tst, pvl, eta, etb, sea, seb, sec, sed, see, seg, seh, sei and sej) and for their distribution in sample types. Eighty-nine isolates were positive for at least one of the genes. Genes for etb, pvl, see and seh were not detected in any of the MRSA isolates. No statistically significant differences in the occurrence of the determinants studied among sample types were found.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální proteiny genetika MeSH
- DNA bakterií analýza izolace a purifikace MeSH
- faktory virulence genetika MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- nemocnice univerzitní MeSH
- polymerázová řetězová reakce MeSH
- prevalence MeSH
- pulzní gelová elektroforéza MeSH
- rezistence na methicilin MeSH
- stafylokokové infekce epidemiologie mikrobiologie MeSH
- Staphylococcus aureus genetika izolace a purifikace patogenita účinky léků MeSH
- virulence genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
... News -- World-wide spread of drug resistant Streptococcus pneumoniae 3 -- Surveillance of antimicrobial ... ... Antimicrobial resistance among bacterial isolates from children. ... ... Trends in antimicrobial resistance among today\'s bacterial pathogens. ... ... Methicillin resistance and beta-lactamase production in Staphylococcus aureus. ... ... Epidemiology of penicillin-resistant Neisseria gonorrhoeae isolated in Taiwan, 1960-1990. ...
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- MeSH
- antibiotická rezistence MeSH
- mikrobiální testy citlivosti MeSH
- náchylnost k nemoci MeSH
- Streptococcus pneumoniae MeSH
- Publikační typ
- sborníky MeSH
- Konspekt
- Mikrobiologie
- NLK Obory
- bakteriologie
- farmacie a farmakologie
- NLK Publikační typ
- brožury