MRSA Infection

PURE Bioscience Launches Proprietary New Brand: PURE Hard Surface Disinfectant

PURE Bioscience Launches Proprietary New Brand: PURE Hard Surface Disinfectant | Business Wire.

PURE Hard Surface provides an unparalleled combination of high efficacy and low toxicity with 30-second bacterial kill times and 24-hour residual protection. PURE Hard Surface completely kills resistant pathogens like MRSA and also effectively eliminates dangerous fungi and viruses including HIV, Norovirus, Influenza A, Avian Influenza and H1N1. PURE Hard Surface is registered for use on food contact surfaces and is gentle enough to be used in sensitive children’s areas. PURE Hard Surface has been registered by the US Environmental Protection Agency and the State of California. The other state registrations are in process.

What drugs for MRSA sufferers coming to emergency departments

Diagnostic and Therapeutic Evaluation of Community-acquired Methicillin-resistant Staphylococcus Aureus (MRSA) Skin and Soft Tissue Infections in the Emergency Department.

The ED antibiogram indicated that 57/58 (98%) CA-MRSA SSTI isolates were susceptible to sulfamethoxazole/trimethoprim (SMX/TMP); 50/58 (86%) isolates were susceptible to tetracycline, and 47/58 (81%) isolates were susceptible to clindamycin. Incision and drainage were performed in 23/25 (92%) patient cases, which was consistent with providers’ perceived habits (100%). SMX/TMP monotherapy was preferred among 23/35 (66%) providers, however, SMX/TMP combined with cephalexin was the antibiotic regimen prescribed in 9/22 (41%) patient cases. Conclusions Cephalexin was often added to cover for potential cellulitis due to Streptococcus spp., however, the surrounding erythema may simply be an extension of the CA-MRSA infection. Department-specific antibiograms are useful in guiding empiric antibiotic selection and may help providers judiciously prescribe antibiotics only when necessary.

Medical students carrying MRSA onto wards

Nasal carriage of methicillin-resistant Staphylococcus aureus among preclinical medical students: epidemiologic and molecular characteristics of methicillin-resistant S. aureus clones.

Between May 2008 and October 2009, a total of 2103 interns were randomly tested for nasal colonization of S. aureus and methicillin-resistant Staphylococcus aureus (MRSA). The prevalence of S. aureus among staphylococci specimens was 23.1%, and among the total S. aureus the MRSA prevalence was 9.4%. MRSA isolates were further subtyped using genetic element staphylococcal cassette chromosome mec (SCCmec) typing, pulsed-field gel electrophoresis (PFGE) band pattern, and multilocus sequence typing. SCCmec type IVa was the most prevalent strain, at 45.4 %. Eleven PFGE patterns were identified in MRSA strains, with 1 predominant (pulsotype A, 45.5%). Eight strains which belonged to clonal complex 78 carried type IVa SCCmec and produced type 3 coagulase. Panton–Valentine leukocidin (PVL) genes (lukS and F-PV) were identified in 10 (45.4%) MRSA strains; these predominately carried ϕSa2958type and ϕSa108PVL-like type PVL phages. After inducing prophages, 8 strains infected other S. aureus isolates and could generate novel PVL-positive strains of S. aureus. The present study demonstrates that interns can carry certain MRSA strains asymptomatically and contribute to the spread of MRSA between the community and hospital.

Fusidic Acid to help Cystic Fibrosis Sufferers with MRSA

Fusidic Acid (TAKSTA™, CEM-102) is Active, In Vitro, Against Methicillin-Resistant Staphylococcus... -- CHAPEL HILL, N.C., April 28, 2011 /PRNewswire/ --.

Researchers from the Hershey Medical Center today announced the publication of research demonstrating that the antibiotic, fusidic acid, is active against MRSA strains isolated from cystic fibrosis (CF) patients. In addition, fusidic acid did not antagonize the activity of two antibiotics, tobramycin and amikacin, that are commonly used in CF patients to treat P. aeruginosa and B. cepacia infections. These results indicate the important role that fusidic acid may play in treating CF patients with MRSA lung infections.

Steam Vacuum Cleaner Machines Add PSI, Heat for Fighting MRSA

Steam Vacuum Cleaner Machines Add PSI, Heat for Fighting MRSA.

Daimer's two upgraded units, the 3000 CVP and 3000 CVGP, offer improvements in both steam temperatures and cleaning pressure. The mid-range steam vacuum cleaner machines are expected to ship with pressure levels rated to 115 psi (up from 96 psi on the preceding models) and steam temperatures rated to 364ºF (up from 329ºF on the preceding models). Both steam vacuum cleaner machines incorporate heavy-gauge vacuum units that feature water- and HEPA-filtration that removes allergens, odors, dustmite waste, and other health-affecting substances. The steam vacuum cleaner machines will offer Daimer's custom, EPA-complying, germ elimination technology, dubbed ATIS®. This boiler-based ionizing subsystem has been laboratory-approved for MRSA elimination and other sterilization applications often found in hospitals as well as educational and business environments.

Cfr gene key to MRSA resistance patterns

The Press Association: Superbug's resistance secret found.

A superbug's resistance secret has been uncovered by scientists, paving the way for new drugs to fight infections. For the first time, researchers have discovered how a key protein helps MRSA (methicillin resistant Staphylococcus aureus) bacteria to evade antibiotics. The Cfr protein acts on the ribosome, a molecular "factory" in cells responsible for making proteins that are vital for survival. Many antibiotics bind on the ribosome in bacteria and stop it functioning, causing the bugs to die. Through a chemical process called methylation, Cfr blocks the binding of antibiotics to the ribosome and at the same time it helps to keep the machinery working. In the case of MRSA, the introduction of Cfr makes the superbug resistant to seven classes of antibiotics. Cfr is made by a mobile gene that can move easily between different species of bacteria.

Digging deeper into genetic roots of MRSA resistance

Abstract | Evidence for a purifying selection acting on the beta-lactamase locus in epidemic clones of methicillin-resistant Staphylococcus aureus.

The beta-lactamase (bla) locus, which confers resistance to penicillins only, may control the transcription of mecA, the central element of methicillin resistance, which is embedded in a polymorphic heterelogous chromosomal cassette (the SCCmec element). In order to assess the eventual correlation between bla allotypes and genetic lineages, SCCmec types and/or beta-lactam resistance phenotypes, the allelic variation on the bla locus was evaluated in a representative collection of 54 international epidemic methicillin-resistant Staphylococcus aureus (MRSA) clinical strains and, for comparative purposes, also in 24 diverse methicillin-susceptible S. aureus (MSSA) strains. Results Internal fragments of blaZ (the beta-lactamase structural gene) were sequenced for all strains. A subset of strains, representative of blaZ allotypes, was further characterized by sequencing of internal fragments of the blaZ transcriptional regulators, blaI and blaR1. Thirteen allotypes for blaZ, nine for blaI and 12 for blaR1 were found. In a total of 121 unique single-nucleotide polymorphisms (SNP) detected, no frameshift mutations were identified and only one nonsense mutation within blaZ was found in a MRSA strain. On average, blaZ alleles were more polymorphic among MSSA than in MRSA (14.7 vs 11.4 SNP/allele). Overall, blaR1 was the most polymorphic gene with an average of 24.8 SNP/allele. No correlation could be established between bla allotypes and genetic lineages, SCCmec types and/or beta-lactam resistance phenotypes. In order to estimate the selection pressure acting on the bla locus, the average dN/dS values were computed. In the three genes and in both collections dN/dS ratios were significantly below 1. Conclusions The data strongly suggests the existence of a purifying selection to maintain the bla locus fully functional even on MRSA strains. Although, this is in agreement with the notion that in most clinical MRSA strains mecA gene is under the control of the bla regulatory genes, these findings also suggest that the apparently redundant function of blaZ gene for the MRSA resistant phenotype is still important for these strains. In addition, the data shows that the sensor-inducer blaR1 is the primary target for the accumulation of mutations in the bla locus, presumably to modulate the response to the presence of beta-lactam antibiotic.

How MRSA Strains Spread Worldwide - Digging Deeper

Testing Spatiotemporal Hypothesis of Bacterial Evolution Using Methicillin-Resistant Staphylococcus aureus ST239 Genome-wide Data within a Bayesian Framework.

Here, we investigated a whole-genome single nucleotide polymorphism (SNP) data set of health care-associated Methicillin-resistant S. aureus sequence type 239 (HA-MRSA ST239) strains, which we analyzed using Markov spatial models that incorporate geographical sampling distributions. The reconstructed timescale indicated a temporal origin of this strain shortly after the introduction of Methicillin, followed by global pandemic spread. The estimate of the temporal origin was robust to the molecular clock, coalescent prior, full/intergenic/synonymous SNP inclusion, and correction for excluded invariant site patterns. Finally, phylogeographic analyses statistically supported the role of human movement in the global dissemination of HA-MRSA ST239, although it was unable to conclusively resolve the location of the root. This study demonstrates that bacterial genomes can indeed contain sufficient evolutionary information to elucidate the temporal and spatial dynamics of transmission. Future applications of this approach to other bacterial strains may provide valuable epidemiological insights that may justify the cost of genome-wide typing.

Targeting PVL to neutralise MRSA?

Thieme eJournals - Abstract.

Both MRSA and P. aeruginosa display resistance to a wide array of antibiotics. Further, both bacteria contain a variety of virulence products or systems that make it difficult to treat associated infections. Within the past several years, community-acquired MRSA containing virulence factors [particularly the Panton-Valentine leukocidin (PVL) gene] has emerged globally. Given the limited number of novel antibiotics to treat antibiotic-resistant organisms, there is growing interest in treating bacterial infections by targeting specific virulence products or systems. This article reviews potential therapeutic targets in the virulence systems of these two bacteria that are responsible for a large number of serious infections in critically ill patients.

Active Ingredient From Chinese Medicine Blocks MRSA Biofilm Formation

Active Ingredient From Chinese Medicine Blocks Biofilm Formation On Medical Implant Materials.

A compound that is an active ingredient in plants commonly used in Chinese medicine prevents biofilm formation on polystyrene and polycarbonate surfaces by Staphylococcus aureus. The research suggests that this compound, 1,2,3,4,6-Penta-O-galloyl-beta-D-glucopyranose (PGG) is highly promising for clinical use in preventing biofilm formation by S. aureus. The paper is published in the March 2011 issue of the journal Antimicrobial Agents and Chemotherapy.

A magnetic bead-based assay for the rapid detection of MRSA

A magnetic bead-based assay for the rapid detection of methicillin-resistant Staphylococcus aureus by using a microfluidic system with integrated loop-mediated isothermal amplification - Lab on a Chip (RSC Publishing).

This study reports a new diagnostic assay for the rapid detection of methicillin-resistant Staphylococcus aureus (MRSA) by combing nucleic acid extraction and isothermal amplification of target nucleic acids in a magnetic bead-based microfluidic system. By using specific probe-conjugated magnetic beads, the target deoxyribonucleic acid (DNA) of the MRSA can be specifically recognized and hybridized onto the surface of the magnetic beads which are then mixed with clinical sample lysates.

Thioridazine combo revives impact of old drug on MRSA

Thioridazine affects transcription of genes involved in cell wall biosynthesis in methicillin-resistant Staphylococcus aureus - Bonde - 2011 - FEMS Microbiology Letters - Wiley Online Library.

The antipsychotic drug thioridazine is a candidate drug for an alternative treatment of infections caused by methicillin-resistant Staphylococcus aureus (MRSA) in combination with the β-lactam antibiotic oxacillin. The drug has been shown to have the capability to resensitize MRSA to oxacillin. We have previously shown that the expression of some resistance genes is abolished after treatment with thioridazine and oxacillin.

Roots of Erythrina variegeta active against MRSA.

Three New Constituents from the Roots of Erythrina... [Chem Biodivers. 2011] - PubMed result.

Two new isoflavonoids, eryvarins V and W (1 and 2, resp.), and a new chromen-4-one derivative, eryvarin X (3), along with three known isoflavonoids, 4-6, were isolated from the roots of Erythrina variegata. Their structures were established by spectroscopic analyses. Compound 1 is a rare naturally occurring isoflavanone which possesses a OH group at C(3). Among the new compounds 1-3, 2 exhibited a potent antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) strains.

One man's infection control can be another man's MRSA posion

Thieme eJournals - Abstract.

Selective decontamination of the digestive tract (SDD) is an infection prevention strategy in intensive care unit (ICU) patients by topical administration of antibiotics to the mouth and stomach to eradicate potentially pathogenic bacteria and yeast that may cause infections. It also includes a short course of intravenous antibiotics to treat incubating infections at the time of ICU admission. Several randomized, controlled studies, all performed in ICUs with low rates of antibiotic resistance, have shown that SDD prevents ventilator-associated pneumonia and improves survival. Surprisingly, SDD was also associated with lower rates of colonization with resistant gram-negative bacteria and no effect on methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Selective oral decontamination (SOD) consisting of oral antibiotics only, without systemic antibiotics or antibiotics given in the stomach, may also increase survival. In areas with low prevalence of MRSA and VRE, SDD should be considered the standard of care in ICUs. In countries where colonization with MRSA and VRE is frequent, resistance may increase, and SDD should be considered experimental therapy. Future research should focus on the effects of SDD compared with SOD on resistance and on SDD-like strategies in areas where MRSA and VRE are endemic.

Antibiotics Lower S. Aureus Risk in Acne Patients

Antibiotics Found to Lower <i>S. Aureus</i> Risk in Acne Patients : Internal Medicine News.

Fewer than 10% of Staphylococcus aureus isolates showed resistance to long-term use of tetracycline antibiotics in a cross-sectional study of 83 patients with acne. Furthermore, the patients on antibiotics for acne showed a lower prevalence of S. aureus than acne patients not on antibiotics. Approximately 40% of the S. aureus isolates were resistant to clindamycin and 44.2% to erythromycin, but all other antibiotics tested (trimethoprim-sulfamethoxazole, ciprofloxacin, doxycycline, and minocycline) showed resistance of less than 10%, reported Dr. Matthew Fanelli and his colleagues from the University of Pennsylvania (Arch. Dermatol. 2011 [doi:10.1001/archdermatol.2011.67]).

How photodynamic inactivation of MRSA works

Finding molecular mechanism of response to photodynamic inactivation of bacteria.

Introduction: In our previous work we observed that Staphylococcus aureus clinical isolates (both MRSA and MSSA) differently respond to photodynamic inactivation (PDI) with the use of porphyrin compounds. In our attempts to determine the molecular marker of strain-dependent response to PDI, we found that biofilm producing strains were killed less efficiently in comparison to non biofilm-producing strains, whereas efflux pumps, e.g., NorA had no influence on the efficacy of photokilling. As cytotoxic effect of PDI against bacterial cells is a consequence of reactive oxygen species action, we further examined if the antioxidant enzymes status influences the response of bacterial cells to PDI.

Chronic CA MRSA sufferers pose problems for hospital infection control

Non-hospital-associated methicillin-resistant Staphylococcus aureus and MRSA chronic carrier patients in infection control.

This study reports research on methicillin-resistant Staphylococcus aureus (MRSA) colonized-infected patients who were admitted to a 320-bed hospital. Specifically, we report on the difficulties related to MRSA infection control as a consequence of the increasing incidence of non-hospital-associated MRSA acquisition and patients as chronic carriers who are frequently readmitted to the hospital.

Daptomycin better than vancomycin against MRSA?

[Role of daptomycin in the empirical and directed ... [Rev Esp Quimioter. 2011] - PubMed result.

Daptomycin is a lipopeptide antibiotic active against Gram-positive bacteria including MRSA and glycopeptide-resistant Enterococcus spp.It is worth mentioning that daptomycin is rapidly bactericidal against methicillin-sensitive S. aureus, more potent than vancomycin and at least as active as isoxazole penicillins. This article discusses the role of this antibiotic in the empirical treatment of infections and directed by Gram-positive bacteria affecting critically ill patients.

7-Pyrrolidino-8-methoxyisothiazoloquinolones highly active against MRSA

Exploration of the Activity of 7-Pyrrolidino-8-methoxyisothiazoloquinolones against Methicillin-Resistant Staphylococcus aureus (MRSA) - Journal of Medicinal Chemistry (ACS Publications).

The 7-[(R)-3-((S)-1-aminoethyl)pyrrolidin-1-yl] analogue (6a(R,S)) and the (R)-7-[3-(2-aminopropan-2-yl)pyrrolidin-1-yl] analogue (7a(R)) were found to be the ITQs with the most promising antibacterial profiles. The MICs of these select ITQs versus a panel of clinical MRSA strains were determined, and the ITQs were found to have 8- to 16-fold greater potency than linezolid. These analogues were also evaluated for inhibition of the target enzymes, topoisomerase IV and DNA gyrase, from both wild-type and multidrug resistant strains. The ITQs were up to >30 times more inhibitory against these targets than the fluoroquinolone moxifloxacin.

TPX assay - 14 hour MRSA test

SpringerLink - European Journal of Clinical Microbiology & Infectious Diseases, Online First™.

The aim of this study was to evaluate a new type of assay for the phenotypic detection of methicillin-resistant Staphylococcus aureus (MRSA). The assay is based on a point-of-care compatible two-photon excitation fluorescence detection technology (TPX). A collection of 243 epidemic MRSA isolates was tested in addition to 138 sporadic MRSA and 101 negative control strains. The assay proved to be both sensitive (97.9%) and specific (94.1%) in the identification of MRSA, with adequate positive (98.4%) and negative (92.2%) predictive values. The time required for obtaining a positive test result was less than 14 h for 99.0% of the MRSA true-positive samples. After a test run, the selectively enriched reaction mixtures may be recovered and further studied by molecular or standard phenotypic methods. The main benefits of the TPX methodology include a simple assay procedure, low reagent consumption, and a high-throughput capacity.