The effect of taurolidine on the time-to-positivity of blood cultures.

Background: Taurolidine containing lock solutions (TL) are a promising method for the prevention of central line associated bloodstream infections. Per accident, the TL may not always be aspirated from the central venous catheter (CVC) before blood cultures are obtained. The TL could, unintentionally, end up in a blood culture vial, possibly altering the results. The aim of this study was to investigate the effect of the TLs on the detection of microbial growth in blood culture vials. Methods: Different lock solutions (taurolidine-citrate-heparin (TCHL), taurolidine, heparin, citrate or NaCl) were added to BD BACTECTM blood culture vials (Plus Aerobic/F, Lytic/10 Anaerobic/F or Peds Plus/F) before spiking with Staphylococcus aureus (ATCC 29213 or a clinical strain) or Escherichia coli (ATCC 25922 or a clinical strain) in the presence and absence of blood. Subsequently, blood culture vials were incubated in the BD BACTEC FX instrument with Time-to-positivity (TTP) as primary outcome. In addition, the effect of the TCHL on a variety of other micro-organisms was tested. Discussion: In the presence of taurolidine, the TTP was considerably delayed or vials even remained negative as compared to vials containing heparin, citrate or NaCl. This effect was dose-dependent. The delayed TTP was much less pronounced in the presence of blood, but still notable. Conclusion: This study stresses the clinical importance of discarding TLs from the CVC before obtaining a blood culture.

The efficacy of taurolidine containing lock solutions for the prevention of central-venous-catheter-related bloodstream infections: a systematic review and meta-analysis.

The incidence of central venous catheter (CVC)-related bloodstream infections is high in patients requiring a long-term CVC. Therefore, infection prevention is of the utmost importance. The aim of this study was to provide an updated overview of randomized controlled trials (RCTs) comparing the efficacy of taurolidine containing lock solutions (TL) to other lock solutions for the prevention of CVC-related bloodstream infections in all patient populations. On 15th February 2021, PubMed, Embase and The Cochrane Library were searched for RCTs comparing the efficacy of TLs for the prevention of CVC-related bloodstream infections with other lock solutions. Exclusion criteria were non-RCTs, studies describing <10 patients and studies using TLs as treatment. Risk of bias was evaluated using the Cochrane Risk of Bias 2 tool. A random effects model was used to pool individual study incidence rate ratios (IRRs). Subgroup analyses were performed based on the following factors: CVC indication, comparator lock and bacterial isolates cultured. A total of 14 articles were included in the qualitative synthesis describing 1219 haemodialysis, total parenteral nutrition and oncology patients. The pooled IRR estimated for all patient groups together (nine studies; 918 patients) was 0.30 (95% confidence interval 0.19-0.46), favouring the TLs. Adverse events (10 studies; 867 patients) were mild and scarce. The quality of the evidence was limited due to a high risk of bias and indirectness of evidence. The use of TLs might be promising for the prevention of CVC-related bloodstream infections. Large-scale RCTs are needed to draw firm conclusions on the efficacy of TLs.

The GI Simulated Clinic in the Era of COVID-19: a Comparison of Virtual to In-Person Delivery.

The COVID-19 pandemic has significantly impacted medical education; thus, there is a need to better understand the effectiveness of virtual learning compared to in-person learning. This is a single-center, cross-sectional study of first-year medical students who attended a gastroenterology simulated clinic activity in person in 2018 and 2019 or virtually in 2020. Participants were surveyed on the activity's relevance and effectiveness. Students' assessment of the virtual clinic's effectiveness and relevance was not significantly different from the in-person version of the activity. In addition, most students rated the virtual clinic as effective for learning about telemedicine.

[Antibiotic prophylaxis not indicated in dental procedures in patients with a joint prosthesis]. / Antibioticaprofylaxe niet geïndiceerd bij tandheelkundige ingrepen bij patiënten met een gewrichtsprothese.

Antibiotic prophylaxis is suggested for high-risk patients undergoing dental procedures to prevent haematogenous infection of the artificial joint. However, randomised placebo-controlled trials are lacking. Case reports are difficult to interpret, because bacteraemias are very common after chewing and tooth brushing anyway. Widespread use of antibiotics has serious downsides. Therefore, more convincing data are needed to support the use of antibiotic prophylaxis for high-risk patients.

Bacterial resistance: a sensitive issue complexity of the challenge and containment strategy in Europe.

The development of antimicrobial agents has been a key achievement of modern medicine. However, their overuse has led to an increasing incidence of infections due to antibiotic-resistant microorganisms. Quantitative figures on the current economic and health impact of antimicrobial resistance are scant, but it is clearly a growing challenge that requires timely action. That action should be at the educational, ethical, economic and political level. An important first step would be to increase public awareness and willingness to take the necessary measures to curb resistance. Hence, studies are needed that would provide solid, quantitative data on the societal impact of antibiotic resistance. This review discusses the complexity of resistance, identifies its main drivers and proposes measures to contain it on a European scale.

Priorities for antibiotic resistance surveillance in Europe.

Antibiotic resistance is an increasing global problem. Surveillance studies are needed to monitor resistance development, to guide local empirical therapy, and to implement timely and adequate countermeasures. To achieve this, surveillance studies must have standardised methodologies, be longitudinal, and cover a sufficiently large and representative population. However, many fall short of these requirements that define good surveillance studies. Moreover, current efforts are dispersed among many, mostly small, initiatives with different objectives. These studies must be tailored to the various reservoirs of antibiotic-resistant bacteria, such as hospitalised patients, nursing homes, the community, animals and food. Two studies that could serve as examples of tailored programmes are the European Antimicrobial Resistance Surveillance System (EARSS), which collects resistance data during the diagnosis of hospitalised patients, and the DANMAP programme, which collects data in the veterinary sector. As already noted by the WHO, genetic studies that include both the typing of isolates and the characterisation of resistance determinants are necessary to understand fully the spread and development of antibiotic resistance.

Primary adenocarcinoma of the bile ducts. Clinical characteristics and natural history.

Primary bile duct carcinoma is a malignancy with a poor prognosis, but recent diagnostic developments allow earlier detection and possibly improved chances for effective palliation or surgical cure. In order to increase the clinical understanding and awareness of this disorder, 43 patients with primary adenocarcinoma of the bile ducts were reviewed. The mean patient age was 63, and symptoms of nausea, abdominal pain, and pruritus were reported in a majority of patients. Documented weight loss, alcoholic stools, cutaneous icterus, and hepatomegaly were each present in a majority of patients. Serum bilirubin and alkaline phosphatase determinations were abnormal in 40 of 43 patients (93%), and cholangiography was the diagnostic study providing the most discriminating information. Locally invasive disease and biliary obstruction was the major cause of morbidity and mortality, and there was only one surgical cure. These data suggest that cholangiography and nonsurgical techniques for biliary drainage should be employed in most patients who are not optimal surgical candidates.

Role of solute drag in intestinal transport.

This study presents experiments related to the role of solvent drag and solute drag in the transmembrane movement of nonelectrolytes in a perfused rat intestine preparation. Conditions were chosen to simulate the effects of luminal hyperosmolarity on the permeability of tracer solutes. Data are presented on net water flux, transepithelial potentials, and lumen-to-blood and blood-to-lumen tracer solute movements during control electrolyte perfusion and after making the perfusate hyperosmotic. The results indicate that both solvent drag and solute drag can play significant roles in the transepithelial movement of solute and solute permeabilities in the rat ileum preparation. It is suggested that the potential roles of solvent drag and solute drag should be accounted for or considered during the characterization of the mechanisms of biological membrane function.

Effects of solvent and solute drag on transmembrane diffusion.

The present study compares and quantitates both solvent drag and solute drag forces in a system with both heteropore and homopore membranes. It is shown that tracer solute permeability can be increased if solution flow or driver solute flux is in the direction of tracer diffusion. Either force can decrease tracer permeability if the force can decrease tracer permeability if the force is opposite to the direction of tracer diffusion. The two forces can be additive or one force may reduce the effect of the other force. In the particular system quantitated, solute drag is shown to be some 300 times more effective than solvent drag on a mole-to-mole basis. The use of a number of solute pairs on other homopore and heteropore membranes confirms the finding that the two drag forces can be analyzed or manipulated in a variety of systems.

The effect of ethanol on ion transport in frog skin.

Frog skin has been used as a model epithelial sodium-transporting system to study the effect of ethanol on ion transport. Treatment of the outside of frog skin with ethanol decreased the net sodium transport due to inhibition of 22Na+ influx. Ethanol did not alter sodium outflux when bathin the outside of the skin. The inhibition was in proportion to the concentration of ethanol, 0.25 M resulting in 50% inhibition. The chloride permeability of the skin was increased several-fold when the skin was exposed to ethanol in either bathing solution. With 0.4 M ethanol in the inner bathing solution, all the unidirectional fluxes of Na+ and C1- were increased. The movement of C1- was evaluated by comparison of C1- flux with urea flux, since urea is thought to move passively across frog skin via an extracellular (shunt) pathway. Chloride flux was increased to a greater extent than urea flux. These experiments indicate that ethanol affects chloride permeability beyond an increase in extracellular ion flow and independent of its effect of Na+ transport.

Solute flux coupling in a homopore membrane.

Our previous studies on solute drag on frog skin and synthetic heteropore membranes have been extended to a synthetic homopore membrane. The 150-A radius pores of this membrane are formed by irradiation and etching of polycarbonate films. The membrane is 6-microm thick and it has 6 x 10(8) pores cm(-2). In this study, sucrose has been used as the driver solute with bulk flow blocked by hydrostatic pressure. As before on heteroporous membranes, the transmembrane asymmetry of tracer solute is dependent on the concentration of the driver solute. Tracer sucrose shows no solute drag while maltotriose shows appreciable solute drag at 1.5 M sucrose. With tracer inulin and dextran, solute drag is detectable at 0.5 M sucrose. These results are in keeping with the previous findings on heteropore membranes. Transmembrane solute drag is the result of kinetic and frictional interaction of the driver and tracer solutes as the driver flows down its concentration gradient. The magnitude of the tracer flux asymmetry is also dependent on the size of the transmembrane pores.

The coupling of solute fluxes in membranes.

Our previous description of solute drag on a synthetic membrane has been extended to include the solutes mannitol, sucrose, raffinose, inulin, and dextran. Labeled and nonlabeled forms of these solutes were used in pairs to quantitate solute flux interaction. Three membranes with pore sizes of 350, 80, and 20 A, respectively, have been utilized. It is shown that solute flux interaction occurs with all the solutes and that the extent of interaction is related directly to solute permeability, concentration, and molecular size. The magnitude of solute interaction is reciprocally related to the radii of the membrane pores, greater interaction occurring with small pored membranes. Solute drag is seen as an increased flux of tracer solute in the direction of the diffusion gradient of a second solute as well as a decreased tracer flux into the diffusion gradient. Values are given for self-diffusion and interaction coefficients as well as for a new coefficient, the "effectiveness coefficient."

Further observations on asymmetrical solute movement across membranes.

The permeability of frog skin under the influence of urea hyperosmolarity has been studied. Flux ratio asymmetry has been demonstrated again for tracer mannitol. The inhibitors DNP, CN(-), and ouabain have been used to eliminate active sodium transport and it was found that urea hyperosmolarity produces asymmetrical mannitol fluxes on frog skins having no short-circuit current. These findings suggest that flux ratio asymmetry is due to solute interaction and is unrelated to sodium transport. Studies with a synthetic membrane show clearly that bulk flow of fluid can produce a "solvent drag" effect and change flux ratios. When bulk flow is blocked and solute gradients allowed their full expression, then solute interaction "solute drag" is easily demonstrable in a synthetic system.

Hyperosmolarity and the net transport of nonelectrolytes in frog skin.

The permeability of frog skin to a series of nonelectrolytes (thiourea, urea, mannitol, and sucrose) under the influence of 2.5 times normal osmolarity in the outer bathing solution has been investigated. Although the flux of the tracer nonelectrolytes across the skin in either direction is greatly increased by hyperosmolarity, the influx is found to be increased to a significantly greater extent than the outflux. Flux ratios as high as 3:1 can be observed. The net inward movement of the nonelectrolyte proceeds in spite of a sizeable bulk flow of water in the opposite direction. Possible driving forces for this phenomenon are discussed.