Virulence Markers in <i>Staphylococcus aureus</i> Strains Isolated from Hemodialysis Catheters of Mexican Patients

Abstract

Methicillin-resistant Staphylococcus aureus is an increasingly important cause of nosocomial bacterial infections worldwide. S. aureus is responsible for several pathologies, including skin infections, endocarditis, meningitis, deeptissue ulcers, and sepsis. S. aureus biofilm formation on catheters and other medical devices is a major post-operative concern, because biofilms are often the source of persistent and difficult to treat bacterial infections. While catheterrelated S. aureus infections have been reported, the strains responsible for these infections have not been genetically characterized. We genetically characterized S. aureus strains isolated from hemodialysis catheters in Mexican patients. The frequency of 35 genes coding for adhesins, toxins, and other virulence-associated products in the 55 isolated S. aureus strains was determined using PCR, while real-time PCR was used to examine the level of gene expression. Of the 55 S. aureus strains isolated from 109 patients, 45 (81.8%) were determined to be methicillin-resistant. The icaA, rbf, sarA, and agr genes are involved in biofilm formation and bacterial dispersion and were detected in 96.3%, 40.0%, 74.5%, and 100% of S. aureus strains, respectively, and 70.9% of the strains formed a detectable biofilm. Interestingly, 67.2% of the strains contained the icaA, agr, spa, clfA, sdrC, sdrD, sdrE, seg, seh, and sei genes, suggesting that this gene combination is important for successful catheter colonization. The results of this study provide significant insight into the virulence gene make-up of catheter-colonizing S. aureus strains, and will assist in developing a more targeted treatment approach for persistent S. aureus biofilm contamination of medical devices.

Antibiotic Susceptibility, Virulence Pattern, and Typing of Staphylococcus aureus Strains Isolated From Variety of Infections in India

“…PCR determined the presence of Staphylococcal enterotoxin (SE) genes encoding for seA , seC , and seI (Monday and Bohach, 1999; Jarraud et al, 2002). Also, the presence of hemolysin genes, hl A and hlG , was determined by PCR (Mitchell et al, 2010; Paniagua-Contreras et al, 2012). PCR was used to detect the presence of collagen adhesion ( cna ) and extracellular fibrinogen binding protein ( efb ) among S. aureus strains (Zecconi et al, 2006).…”

Rhamnolipids, Microbial Virulence Factors, in Alzheimer’s Disease

“…Bacterial antigens and AD-like pathology have been detected in the CNS of BALB/c mice models resulting from intranasal infection due to a strain of Chlamydia pneumoniae [20]. An excessive amount of virulence markers encoded virulence-related genes which have been recorded to originate from Staphylococcus aureus strains isolated from hemodialysis catheters of Mexican patients; they were held responsible for nosocomial bacterial infections due to biofilm formation [72].…”

“…The CSF samples were taken from different individuals than those who provided the serum samples. The average age of AD patients was 75 years (56-85), of MCI patients 70 years , and of controls 73.3 years (68)(69)(70)(71)(72)(73)(74)(75)(76)(77)(78)(79)(80)(81). Each sample was assayed in duplicate.…”

A Novel Antimicrobial Coating Represses Biofilm and Virulence-Related Genes in Methicillin-Resistant Staphylococcus aureus

“…Methicillin-resistant Staphylococcus aureus (MRSA) is a crucial human pathogen causing infections ranging from skin and soft tissue infections to fatal sepsis ( Marathe et al, 2015 ). It is one of the leading pathogens that cause nosocomial infections ( Paniagua-Contreras et al, 2012 ; Lister and Horswill, 2014 ); it is resistant to methicillin and many other antibiotics ( Marathe et al, 2015 ), and it is also known to produce thick biofilm ( Paniagua-Contreras et al, 2012 ; Qin et al, 2014 ). MRSA was shown to cause catheter-associated and other medical devices-related infections ( Arciola et al, 2001 ; Paniagua-Contreras et al, 2012 ).…”