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S. Aureus Strains Isolated (s + aureu_strain_isolated)
Selected AbstractsStaphylococcus aureus as source of catheter-related bloodstream infection evaluated by PFGE and rep-PCR typing in a Brazilian hospital,APMIS, Issue 11 2008GERALDO SADOYAMA Staphylococci are a common cause of catheter-related bloodstream infection (CR-BSI), and epidemiological typing is an important tool for effective infection control. This study evaluated by PFGE and rep-PCR whether Staphylococcus aureus strains isolated from skin and catheter tips were related to specimens isolated from blood. A prospective observational study, carried out in a clinical surgical ward at a Brazilian hospital between September 2000 and November 2002, investigated non-tunneled central venous catheters from 179 patients. S. aureus isolates were mainly obtained from blood (41.4%), while coagulase-negative staphylococci strains were more often isolated from the skin at the catheter insertion site (49.7%) and from the catheter tip (57.5%). Among the 21 strains isolated from 9 patients at 2 or 3 sites simultaneously, 9 were methicillin-resistant S. aureus (MRSA) and 12 were methicillin-susceptible S. aureus (MSSA). Seven patients harbored the same S. aureus strain isolated from the skin, blood and/or catheter tip cultures. MRSA isolates belonged to one PFGE pattern (type A- subtypes A1, A2 and A3), and to two rep-PCR patterns (a and b). MSSA isolates were distinguished in five PFGE (B to F) and in three rep-PCR (c, d and e) patterns. Both PFGE and rep-PCR methods indicated that the skin at the catheter insertion site was the origin of CR-BSI caused by S. aureus. [source] Detection by PCR of adhesins genes and slime production in clinical Staphylococcus aureusJOURNAL OF BASIC MICROBIOLOGY, Issue 4 2008Tarek Zmantar Abstract The presence of the ica loci and adhesins genes in clinical Staphylococcus aureus strains were considered important factors of virulence. In this study, 46 strains of Staphylococcus aureus were isolated from auricular infection, and were investigated for slime production using Congo Red Agar method (CRA). In order to detect the adhesins genes (ica A, ica D, fnb A, cna, Clf A) Polymerase Chain Reaction was used. Qualitative biofilm production of S. aureus using CRA plates revealed that 56.5% of strains were slime producers. In addition 78.26% of strains were ica A and ica D positive. While the fnbA gene was present in 76.1% of isolated strains. Furthermore, 56.5% of strains have the cna gene and 30.4% were clfA positives. Overall this study confirms the presence of fnb A and ica A/ica D genes in the majority of studies S. aureus strains isolated from Staphylococcal sepsis. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Are there predominant strains and toxins of Staphylococcus aureus in atopic dermatitis patients?THE JOURNAL OF DERMATOLOGY, Issue 2 2009Genotypic characterization, adult patients with atopic dermatitis, toxin determination of S. aureus isolated in adolescent ABSTRACT The colonization of Staphylococcus aureus is one of the most important aggravating factors of atopic dermatitis (AD). Until now, the importance of S. aureus in AD and a positive correlation between colonization with S. aureus and clinical severity/skin barrier function has been demonstrated. The aim of this study was to determine whether there are certain clones of S. aureus which colonize the skin of AD patients. For this purpose, the genotype of S. aureus isolated from AD patients was examined by newly-developed typing methods. With 36 strains of S. aureus isolated from 35 patients with AD, spa typing, multi-locus sequence typing (MLST), and staphylococcal toxin gene assay by multiplex polymerase chain reaction, were performed. Clinical severity and skin barrier function were evaluated with eczema area and severity index (EASI) and with transepidermal water loss (TEWL). Among 36 strains of S. aureus, 14 sequence types (ST) and 20 spa types were identified, suggesting a very heterogeneous genetic composition of S. aureus and the absence of a prevailing genotype in S. aureus colonized with AD patients. Furthermore, there was no specific genotype of S. aureus which was associated with the clinical severity of AD or skin barrier dysfunction. A toxin gene assay, however, showed the predominance of S. aureus strains carrying sea and/or tsst-1. To the best of our knowledge, this is the first report to show the genetic composition of S. aureus strains isolated from AD patients determined by sequence-based typing methods. [source] Staphylococcus aureus: colonizing features and influence of an antibacterial treatment in adults with atopic dermatitisBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2002K. Breuer SummaryBackground,,The skin of up to 100% of patients with atopic dermatitis (AD) is colonized with Staphylococcus aureus. Of all S. aureus strains isolated from lesional skin, up to 65% have been shown to produce exotoxins with superantigenic properties. Patients colonized with S. aureus have been treated with antibiotics in several open and double-blind placebo-controlled studies, with conflicting results. These studies did not consider the anterior nares as a reservoir of S. aureus, or the possibility of transmission between patients and their contacts. Moreover, adult patients have not so far been investigated. Objectives,,To investigate the colonizing features of S. aureus in adults with AD and in their contacts, and the effect of an antimicrobial treatment of the patients and their partners. Methods,Swabs were taken from the skin and anterior nares of 66 adults with AD. S. aureus strains were screened for the production of exotoxins in 32 patients. Ten patients (two with toxigenic strains, eight with non-toxigenic strains) were treated orally with cefalexin, chlorhexidine ointment was applied to the skin, and the anterior nares were treated with mupirocin ointment. A bath containing potassium permanganate was taken daily. In addition, their partners were treated topically. Results,,Sixty-two of 66 patients (94%) were carriers of S. aureus, and mostly harboured the bacteria on both skin and anterior nares. Ten of 32 (31%) patients were colonized with toxigenic strains. The Severity Scoring in AD (SCORAD) score decreased in nine of 10 patients who received antimicrobial treatment (P < 0·001), and this effect was more pronounced in patients with a baseline SCORAD >,50. Conclusions,,S. aureus may play an important role as an aggravating factor in adults with AD, as antimicrobial treatment leads to a significant improvement of AD in patients who are colonized with the bacterium. [source] Staphylococcus aureus enterotoxins induce histamine and leukotriene release in patients with atopic eczemaBRITISH JOURNAL OF DERMATOLOGY, Issue 2 2001J. Wehner Background Chronic skin colonization with Staphylococcus aureus is a characteristic feature of atopic eczema (AE), and about 60% of S. aureus strains isolated from the skin of patients with AE secrete enterotoxins. Furthermore, IgE antibodies to S. aureus enterotoxins have been identified in 78% of patients with AE. Objectives To examine the S. aureus enterotoxin-induced histamine and leukotriene release of basophils from patients with AE. Methods Peripheral blood basophils from patients with AE were stimulated with the staphylococcal enterotoxins A, B, D, E and toxic shock syndrome toxin-1. Additionally, priming experiments were performed with interleukin (IL)-3, IL-8 and granulocyte/macrophage colony-stimulating factor followed by stimulation with S. aureus enterotoxins. Results In patients with AE, basophils secreted significantly higher amounts of histamine and leukotriene C4 (LTC4) than in healthy controls. The priming experiments showed additional histamine and LTC4 release in the group of AE patients. Conclusions Histamine and leukotriene generation from atopic basophils stimulated with staphylococcal enterotoxins may indicate a role for these toxins as possible allergens in at least a subgroup of patients with AE. [source] | ||||||||||