Use of BioFire FilmArray gastrointestinal PCR panel associated with reductions in antibiotic use, time to optimal antibiotics, and length of stay.

BACKGROUND: Rapid and accurate diagnostic tools are needed for appropriate management of infectious diarrhea. METHODS: We evaluated the impact of the introduction of rapid multiplex PCR testing using the FilmArray gastrointestinal (GI) panel (BioFire Diagnostics, LLC, Salt Lake City, UT) at our institution, and compared the results to those of standard stool cultures. RESULTS: The most common pathogens detected by the FilmArray GI panel were Clostridium difficile (55.0%), Campylobacter species (20.9%), Salmonella species (12.4%), and Shigella/EIEC species (12.4%). Rates of reproducibility in stool culture for these pathogens ranged from 56.3 to 77.8%. Co-detection of two or more organisms was common (24.2%), most commonly involving EPEC, EAEC, ETEC, and STEC. The time from arrival in the Emergency Department to discharge or admission to the hospital was unchanged after the introduction of FilmArray GI panel, but length of hospital stay was shorter (3 vs. 7.5 days, p = 0.0002) for the FilmArray group. The time to empiric antibiotics did not differ significantly, but optimal antibiotics were started earlier after introduction of the FilmArray GI panel (hospital day 1 vs. 2, p < 0.0001). More patients were discharged without antibiotics after introduction of the FilmArray GI panel (14.0% vs. 4.5%; p < 0.001). CONCLUSION: Our results demonstrate that the FilmArray GI panel is an important tool for improving both patient care and antibiotic stewardship, despite the tendency for positive results with multiple pathogens.

HIV infection induces structural and functional changes in high density lipoproteins.

BACKGROUND AND AIMS: Coronary artery disease is a growing clinical problem in HIV-infected subjects. The increased risk of coronary events in this population has been linked to low levels of HDL, but the effects of HIV infection and anti-retroviral treatment (ART) on HDL structure and function remain unknown. Here, we aimed to determine the composition and function of HDL particles isolated from ART-naive and ART-positive HIV-infected patients. METHODS AND RESULTS: Proteomic profiling revealed decreased levels of paraoxonase (PON) 1 and PON 3 in HDL from HIV patients relative to HDL from uninfected controls (p < 0.0001), and PON activity of HDL from control group (0.13 ± 0.01 U/µl) was significantly higher than PON activity of HDL from HIV-infected untreated subjects (0.12 ± 0.01 U/µl, p = 0.0035), subjects treated with non-nucleoside reverse transcriptase inhibitor (NNRTI)-based therapy (0.11 ± 0.01 U/µl, p < 0.0001), subjects treated with protease inhibitor (PI)-based therapy with detectable viral load (0.11 ± 0.01 U/µl, p < 0.0001), and PI-treated patients with undetectable viral load (0.12 ± 0.01 U/µl, p = 0.0164). Lipidomic profiling uncovered a negative correlation between CD4 T cell counts and particle sphingomyelin, lyso-phosphatidylcholine and ether-linked phosphatidylserine content in the ART-naive (R(2) = 0.2611, p < 0.05; R(2) = 0.2722, p < 0.05; and R(2) = 0.3977, p < 0.05, respectively) but not treated HIV-infected subjects. Functional analysis demonstrated a negative correlation between cholesterol efflux capacity of HDL and viral load in the ART-naive HIV-infected group (R(2) = 0.26, p = 0.026). CONCLUSIONS: Taken together, these results indicate that HIV infection associates with a number of both protein and lipid compositional changes in HDL particles. Moreover, HIV infection affects cholesterol efflux function of HDL, thus contributing to an increased risk of atherosclerosis in this patient population.

Induction of MRSA Biofilm by Low-Dose ß-Lactam Antibiotics: Specificity, Prevalence and Dose-Response Effects.

Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of hospital- and community-associated infections. The formation of adherent clusters of cells known as biofilms is an important virulence factor in MRSA pathogenesis. Previous studies showed that subminimal inhibitory (sub-MIC) concentrations of methicillin induce biofilm formation in the community-associated MRSA strain LAC. In this study we measured the ability sub-MIC concentrations of eight other ß-lactam antibiotics and six non-ß-lactam antibiotics to induce LAC biofilm. All eight ß-lactam antibiotics, but none of the non-ß-lactam antibiotics, induced LAC biofilm. The dose-response effects of the eight ß-lactam antibiotics on LAC biofilm varied from biphasic and bimodal to near-linear. We also found that sub-MIC methicillin induced biofilm in 33 out of 39 additional MRSA clinical isolates, which also exhibited biphasic, bimodal and linear dose-response curves. The amount of biofilm formation induced by sub-MIC methicillin was inversely proportional to the susceptibility of each strain to methicillin. Our results demonstrate that induction of biofilm by sub-MIC antibiotics is a common phenotype among MRSA clinical strains and is specific for ß-lactam antibiotics. These findings may have relevance to the use of ß-lactam antibiotics in clinical and agricultural settings.

Diabetic foot infections: the role of microbiology and antibiotic treatment.

Diabetes mellitus is a major risk factor for the development of foot infections. Among the risk factors that contribute to the development of diabetic foot infections are local neuropathy, vascular changes and depressed local host defenses. The microbiology of these infections is often complex and can be polymicrobial. Treatment of these infections depends on the severity and extent of infection. Treatment should involve a multi-disciplinary team approach involving surgeons and infectious disease specialists. The current recommendations for treatment are primarily based on expert opinion and consensus rather than clinical trials. No single agent or combination of agents has been shown to be superior to others. The aim of this review is to provide valid options of therapy, especially with regard to newer agents that are currently available for treatment of both soft tissue infections and osteomyelitis.

Thrombosis and infection: a case of transient anti-cardiolipin antibody associated with pylephlebitis.

Infections with Bacteroides species have been noted to occur in association with cases of thrombophlebitis. This association has led to the speculation that the microorganisms themselves may contribute to the pathogenesis of thrombus formation through elaborated enzymes, including heparinases, or by interactions between the clotting cascade and the unique structure of the Bacteroides lipopolysaccharide. Anti-phospholipid antibodies have been linked with hypercoagulable states and thrombus formation. Although a number of infections have been associated with the transient production of anti-cardiolipin antibodies, the effect the antibodies may have in contributing to thrombus formation is not well understood. The occurrence of Bacteroides species infection with transient anti-cardiolipin antibody has not been previously reported.

Effect of delavirdine on plasma lipids and lipoproteins in patients receiving antiretroviral therapy.

Plasma lipid and lipoprotein levels were measured at baseline and after 8 weeks of highly active antiretroviral therapy among patients receiving delavirdine with or without a protease inhibitor (PI). In patients receiving nucleoside reverse transcriptase inhibitors (NRTI) plus delavirdine, there was a statistically significant increase in cholesterol and HDL levels, whereas those receiving NRTI plus a PI had no significant change in their HDL levels. When delavirdine was combined with a PI, there was a more dramatic increase in both cholesterol and HDL concentrations.