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Few studies assess the utility of rapid multiplex molecular respiratory panels in adult patients. Previous multiplex PCR assays took hours to days from order time to result. We analyze the clinical impact of switching to a molecular assay with a 3-h test-turnaround-time (TAT). We performed a retrospective review of adult patients who presented to our emergency departments with respiratory symptoms and had a respiratory viral panel (xTAG RVP; RVP) or respiratory pathogen panel (ePlex RP; RPP) within 48 h of presentation. The average TATs for the RVP and RPP were 27.9 and 3.0 h, respectively ( P < 0.0001). In RVP-positive and RPP-positive patients, 68.9 and 44.5% of those with normal chest imaging received antibiotics ( P = 0.013), while 95.4 and 89.6% of those with abnormal imaging received antibiotics, respectively ( P = 0.187). There was no difference in antibiotic duration in RVP-positive and RPP-positive patients with abnormal chest imaging (6.2 and 6.0 days, respectively; P = 0.923) and normal chest imaging (4.5 and 4.3 days, respectively; P = 0.922). Fewer patients were admitted in the RPP-positive compared to the RVP-positive group (76.9 and 88.6%, respectively; P = 0.013), while the proportion of admissions were similar among RPP-negative and RVP-negative patients (85.3 and 87.1%, P = 0.726). Switching to a multiplex respiratory panel with a clinically actionable TAT is associated with reduced hospital admissions and, in admitted adults without focal radiographic findings, reduced antibiotic initiation. Opportunities to further mitigate inappropriate antibiotic use may be realized by combining rapid multiplex PCR with provider education, clinical decision-care algorithms, and active antibiotic stewardship., (Copyright © 2019 Weiss et al.)

Antimicrobial lock solutions are important for prevention of microbial colonization and infection of long-term central venous catheters. We investigated the efficacy and safety of a novel antibiotic-free lock solution formed from gas plasma-activated disinfectant (PAD). Using a luminal biofilm model, viable cells of methicillin-resistant Staphylococcus aureus , Staphylococcus epidermidis , Pseudomonas aeruginosa , and Candida albicans in mature biofilms were reduced by 6 to 8 orders of magnitude with a PAD lock for 60 min. Subsequent 24-h incubation of PAD-treated samples resulted in no detectable regrowth of viable bacteria or fungi. As a comparison, the use of a minocycline-EDTA-ethanol lock solution for 60 min led to regrowth of bacteria and fungi, up to 10 7 to 10 9 CFU/ml, in 24 h. The PAD lock solution had minimal impact on human umbilical vein endothelial cell viability, whereas the minocycline-EDTA-ethanol solution elicited cell death in nearly half of human endothelial cells. Additionally, PAD treatment caused little topological change to catheter materials. In conclusion, PAD represents a novel antibiotic-free, noncytotoxic lock solution that elicits rapid and broad-spectrum eradication of biofilm-laden microbes and shows promise for the prevention and treatment of intravascular catheter infections., (Copyright © 2018 American Society for Microbiology.)

We reviewed data for almost 300,000 clinical Escherichia coli urinary isolates (collected in 2009 through 2013) from 127 inpatient and outpatient facilities, to assess antibiotic resistance among Veterans Affairs health care system patients using Clinical and Laboratory Standards Institute and Centers for Disease Control and Prevention National Healthcare Safety Network definitions or guidance. Rates of resistance to amoxicillin or ampicillin/β-lactamase inhibitors were approximately 40% and rates of resistance to fluoroquinolones and trimethoprim-sulfamethoxazole approached 30%. Rates of resistance to nitrofurantoin, antipseudomonal penicillin/β-lactamase inhibitors, and carbapenems remained less than 10%. The percentage of isolates that were considered multidrug resistant varied (4% to 37%), depending on the definitions used., (Copyright © 2017 American Society for Microbiology.)

We quantified methicillin-resistant Staphylococcus aureus (MRSA) carriage. The greater the log(10) count in samples from the nares, the greater the likelihood that other body sites had been colonized. Log(10) counts among body sites were correlated. The greatest sensitivity value (98%) was determined for the combined results from 2 sites: the nares and the groin.

We investigated the activities of telavancin and vancomycin against biofilm-producing Staphylococcus and Enterococcus strains. At clinically attainable concentrations, telavancin was active against bacteria embedded in biofilm (minimal biofilm eradication concentration [MBEC], 0.125 to 2 microg/ml) and inhibited biofilm formation at concentrations below the MIC. Vancomycin did not demonstrate the same activity (MBEC, > or =512 microg/ml) against Staphylococcus aureus and Enterococcus faecalis. Telavancin may have a unique role in biofilm-associated infections.

Intravascular catheter-associated bloodstream infections significantly increase rates of morbidity and hospital costs. Microbial colonization and development of biofilms, which are known to be recalcitrant to antibiotic therapy, often lead to the loss of otherwise patent vascular access systems. We evaluated a new taurolidine- and citrate-based catheter lock solution (Neutrolin; Biolink Corporation, Norwell, Mass.) for its activity against planktonic microbes, antimicrobial activity in a catheter model, and biofilm eradication activity. In studies of planktonic microbes, after 24 h of contact, 675 mg of taurolidine-citrate solution per liter caused > 99% reductions in the initial counts of Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Entercoccus faecalis. A solution of 13,500 mg/liter was cidal for Candida albicans. Ports and attached catheters inoculated with 50 to 600 CFU of these bloodstream isolates per ml were locked with heparin or the taurolidine-citrate solution. After 72 h, there was no growth in the taurolidine-citrate-treated devices but the heparin-treated devices exhibited growth in the range of 6 x 10(2) to 5 x 10(6) CFU/ml. Biofilms were developed on silicone disks in modified Robbins devices with broth containing 6% serum (initial counts, 10(6) to 10(8) CFU/cm(2)). The axenic biofilms were treated for 24 h with taurolidine-citrate or heparin. Taurolidine-citrate exposure resulted in a median reduction of 4.8 logs, whereas heparin treatment resulted in a median reduction of 1.7 logs (P < 0.01). No significant differences in the effects of the two treatments against P. aeruginosa and C. albicans were observed. These findings suggest that taurolidine-citrate is a promising combination agent for the prevention and treatment of intravascular catheter-related infections.

Staphylococcus epidermidis is a major cause of infections associated with indwelling medical devices. Biofilm production is an important virulence attribute in the pathogenesis of device-related infections. Therefore, elimination of these biofilms is an ideal treatment. Salicylate (5 mM) combined with 1 microg of vancomycin per ml inhibited biofilm formation by S. epidermidis (RP62A) by >or=99.9%. When biofilm-coated polystyrene beads were exposed to 5 mM sodium salicylate and 4 microg of vancomycin per ml (one-half the minimum biofilm eradication concentration), there was a >99.9% reduction in viable count.

Laboratory technologists (22%) developed infections with Shigella sonnei. The isolates had the same antibiogram and pulse-field gel electrophoresis pattern as an unknown isolate handled by a laboratory student. Covering faucet handles with paper towels during hand washing in the laboratory was protective. No further cases occurred after the laboratory was cleaned with a phenolic agent and a handle-free faucet was installed.

An outbreak of community-acquired Legionnaires' disease (LD) occurred in Providence, R.I., in fall 1993. To find the outbreak source, exposures of 17 case patients were compared to those of 33 matched controls. Case patients were more likely than controls to have visited a section of downtown (area A) during the 2 weeks before illness (11 [65%] versus 9 [27%]; matched odds ratio, 6.5; P = 0.01). Water samples were cultured from 27 aerosol-producing devices within area A. Legionella pneumophila serogroup 1 isolates underwent monoclonal antibody (MAb) subtyping and arbitrarily primed PCR (AP-PCR). All four L. pneumophila serogroup 1 isolates available from case patients who visited area A had identical MAb and AP-PCR patterns. Among 14 environmental isolates, 5 had MAb patterns that matched the case patient isolates, but only 1 had a matching AP-PCR pattern. This investigation implicates a cooling tower in area A as the outbreak source and illustrates the usefulness of AP-PCR for identifying sources of LD outbreaks.

A Campylobacter jejuni strain of serotype O:10 was isolated from a patient who had Miller-Fisher syndrome. In its biochemical reactions and cellular morphology, the isolate was characteristic of typical C. jejuni. Antibodies against extracted lipopolysaccharide (LPS) were detected by passive hemagglutination in the acute- and convalescent-phase patient sera. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting with the O:10 antiserum, it was demonstrated that the strain possessed both low- and high-molecular-weight molecules. Chemical analysis of the LPS revealed that the core oligosaccharide has a terminal trisaccharide epitope consisting of two molecules of sialic acid linked to galactose, a structure reflecting the terminal region of human ganglioside GD3. As this trisaccharide is also present in LPS cores of serotype O:19 strains from patients with Guillain-Barré syndrome but not in cores of nonneuropathic C. jejuni, a possible role for the trisaccharide in the etiology of neuropathies is indicated, and a difference for distinguishing neuropathic strains from nonneuropathic strains may be the presence of a sialyltransferase required for the synthesis of this trisaccharide.

Arbitrarily primed PCR (AP-PCR) and pulsed-field gel electrophoresis (PFGE) subtyping were applied to clinical and environmental isolates from seven unrelated outbreaks of Legionnaires' disease. The patterns observed with each method matched patient isolates and the epidemiologically linked source of disease for each of the seven outbreaks. PFGE allowed more discrimination among various isolates, although AP-PCR usually gave comparable results. With both methods, certain patterns appeared to predominate in the comparison of the seven outbreaks. Of five clinical isolates not associated with the outbreaks, three gave profiles distinct from those observed in the outbreaks by both methods. This suggests that there are at least two predominant subtypes of Legionella pneumophila serogroup 1 associated with outbreaks. Investigations of outbreaks of legionellosis should employ either PFGE or AP-PCR in addition to monoclonal antibody analysis.