Adherence characteristics of coagulase-negative staphylococci isolated from patients with infective endocarditis

Abstract

Summary. Coagulase-negative staphylococci isolated from patients with endocarditis were divided according to whether the infection was of native or of prosthetic valves and was acquired either in the community or in hospital. Comparisons were made with strains from intravenous line-associated bacteraemias. All strains were examined by direct and indirect adherence tests. Line-associated bacteraemia strains were more likely to produce slime and were more hydrophilic but were less likely to attach HEp2 tissue culture cells than were endocarditis strains, and almost equally likely to adhere to plastic and extracellular matrix proteins. Amongst the endocarditis strains, there was little difference in slime production but hospital-acquired or prosthetic-valve strains were more hydrophobic and more likely to adhere to silicone than were the native-valve or community-acquired strains. Exposure of extracellular matrix proteins on native valves due to a pre-existing non-infective heart condition may account for the selection of strains able to adhere to fibronectin or laminin.

Newly-synthesized chalcones-inhibition of adherence and biofilm formation of methicillin-resistant Staphylococcus aureus

“…Discrepancy between these two methods was low and in accordance with the results of other authors (Freeman et al , 1989; Cree et al , 1995). CRA and Christhensen methods are qualitative and not 100% reliable since Christhensen method shows low success for detection of weak slime production (Christensen et al , 1982) and results obtained from CRA method can often be misinterpreted due to variation in black pigmentation of colonies or decrease of the black color with the time (Freeman et al , 1989; Mariana et al , 2009).…”

“…Plates were incubated on 35 °C in aerobic conditions for 24 h after which results were interpreted according to following criteria: black colonies with dry crystalline consistency indicated for the positive result (slime production), pink colonies were usually present at non-slime producers and darkening of the colonies with the absence of the dry-crystalline morphology was categorized as indeterminate result (Freeman et al , 1989: Cree et al , 1995). …”

Assessment of ica operon carriage and biofilm production in Staphylococcus epidermidis isolates causing bacteraemia in bone marrow transplant recipients

“…Second, although biofilm production per se cannot be used to decide on the need to treat S. epidermidis bacteraemias, differences were found between patients infected by isolates either producing or failing to produce biofilm. Several studies have attempted to evaluate the role of biofilm production in virulence, but the results have been somewhat contradictory [17][18][19][20]. However, recent clinical studies have suggested that PIA is important for biofilm accumulation, and that the presence of the icaADBC operon coding for PIA is related to the clinical significance of S. epidermidis isolates [4][5][6][7][8][21][22][23].…”

New Developments in Diagnosis and Treatment of Infection in Orthopedic Implants

“…Glycocalix promotes intercellular adhesion, captures nutrients, and protects microorganisms from the deleterious effects of antimicrobial agents. Many investigators consider slime a virulence factor, because strains of CNS from prosthetic valve endocarditis are more likely to produce it than are those not cultured at University of Nebraka-Lincoln Libraries on April 4, 2015 http://cid.oxfordjournals.org/ Downloaded from from such infections [26]. Christensen et al [27] clearly showed that slime-producing CNS are more likely to be isolated from a device than from random blood cultures.…”