Control of microbial contamination in dental unit water systems using tetra-sodium EDTA.

Aim: To examine the efficacy of tetra-sodium EDTA in controlling microbial contamination of dental unit water systems (DUWS).

Methods And Results: Ten dental units were treated once a week with either 4% or 8% tetra-sodium EDTA for four or two consecutive weeks, respectively. Before treatment, 43% and 60% of the water samples from the air/water triple syringe and high-speed hand-pieces, respectively, exceeded the American Dental Association (ADA) guidelines of 200 CFU ml(-1) water during a 6-week baseline period.

The effect of EDTA instillations on the rate of development of encrustation and biofilms in Foley catheters.

The aim of this research was to examine whether a daily instillation of tetra sodium ethylenediaminetetraacetic acid (EDTA) solution could reduce the rate at which encrustation by crystalline Proteus mirabilis biofilms blocks urinary catheters. Sets of three bladder models were fitted with size 14 all-silicone catheters. Tetra sodium EDTA solution was instilled into the catheter following biofilm development.

Inhibition of biofilms associated with dentures and toothbrushes by tetrasodium EDTA.

Aims: We examined the efficacy of tetrasodium EDTA in eradicating biofilms derived from salivary inocula or pure cultures of Candida albicans on discs of polymethyl methacrylate (PMMA) denture base or on toothbrushes that had been used normally for 4-8 weeks. Its efficiency in virus neutralization was also determined.

Methods And Results: Overnight (16 h) treatment with 4% (w/v) tetrasodium EDTA solution reduced salivary and C.

Intravascular catheters and biofilm control.

Intravascular catheters are the most common cause of nosocomially acquired bloodstream infections. Bacteria found adhering to the intraluminal surfaces of catheters are the principal source and cause of these infections. Adherent bacteria overtime are known to form multicellular communities which become encased within a three dimensional matrix of extracellular polymeric material known as biofilms, which are thought to be responsible for persistent infections.

Tetrasodium EDTA as a novel central venous catheter lock solution against biofilm.

Background: Central venous catheter (CVC)-related bloodstream infections (BSIs) are known to increase rates of morbidity and mortality in both inpatients and outpatients, including hematology-oncology patients and those undergoing hemodialysis or home infusion therapy. Biofilm-associated organisms on the lumens of these catheters have reduced susceptibility to antimicrobial chemotherapy. This study tested the efficacy of tetrasodium EDTA as a catheter lock solution on biofilms of several clinically relevant microorganisms.

In situ diagnosis of intravascular catheter-related bloodstream infection: a comparison of quantitative culture, differential time to positivity, and endoluminal brushing.

Objective: To compare the accuracy of three techniques that do not require central venous catheter removal to diagnose catheter-related bloodstream infection.

Design: Prospective cohort study of central venous catheters from suspected cases of catheter-related bloodstream infection.

Setting: University teaching hospital.

In situ endoluminal brushing: a safe technique for the diagnosis of catheter-related bloodstream infection.

We assessed the safety of the endoluminal brush technique for the in situ diagnosis of central-venous-catheter (CVC)-related bloodstream infection (CRBSI). The endoluminal brush was used to investigate patients with suspected CRBSI by sampling the CVC lumen to within 3-5 cm of the catheter tip (the brush was kinked to mark the length required). Quantitative peripheral blood cultures were taken 1 min pre-brushing and 1 min and 1h post-brushing.

Use of in vivo-generated biofilms from hemodialysis catheters to test the efficacy of a novel antimicrobial catheter lock for biofilm eradication in vitro.

This biofilm study was conducted to assess the in vitro activity of tetrasodium EDTA on catheters that had been routinely removed from hemodialysis patients at Leeds Teaching Hospitals Trust due to maturation of fistula. Catheters were screened by culture of through-catheter flush, and isolates were identified by standard methodologies; 20 isolates were found to be biofilm positive. Initial biofilm cell count levels averaged above 10(5) CFU/1-cm catheter section.

The routine microbiological screening of central venous catheters in home parenteral nutrition patients.

Background & Aims: Catheter-related bloodstream infection (CRBSI) is a major complication for patients receiving home parenteral nutrition (HTPN). Endoluminal sampling techniques allow the diagnosis of CRBSI without catheter removal and may allow the screening of asymptomatic patients.

Methods: Over a 5-year period, patients receiving HTPN were offered screening on a 3 monthly basis.

Prevention of catheter related bloodstream infection by silver iontophoretic central venous catheters: a randomised controlled trial.

Aim: To evaluate the efficacy of silver iontophoretic central venous catheters in preventing catheter related colonisation and bloodstream infection among high risk patients in a tertiary hospital.

Methods: Patients requiring central venous access for a period greater than seven days were stratified into two groups according to systemic inflammatory response syndrome criteria before being randomly assigned to receive either silver iontophoretic or control catheters. The incidence of catheter colonisation and catheter related bloodstream infection (CRBSI) was recorded.

Calcitonin precursors: early markers of gut barrier dysfunction in patients with acute pancreatitis.

Background: Severe acute pancreatitis is associated with an early increase in intestinal permeability and endotoxemia. Endotoxin is a potent stimulator for the production and release of procalcitonin and its components (calcitonin precursors; [CTpr]). The aim of this study is to evaluate the role of plasma CTpr as an early marker for gut barrier dysfunction in patients with acute pancreatitis.

Each lumen is a potential source of central venous catheter-related bloodstream infection.

Objective: To determine the relative rates of microbial colonization of individual lumens in triple-lumen central venous catheters (CVCs) and calculate the chance of detecting catheter-related blood stream infection (CRBSI) if only one lumen is sampled.

Design: Prospective evaluation of CVCs from suspected and nonsuspected CRBSI cases.

Setting: University teaching hospital.

The use of a rapid in situ test in the detection of central venous catheter-related bloodstream infection: a prospective study.

Background: Acridine orange leukocyte cytospin (AOLC) is a highly sensitive and specific test for the detection of catheter-related bloodstream infection (CRBSI). We evaluated the role of the AOLC test in early detection or exclusion of CRBSI and compared the cost of managing patients with suspected CRBSI.

Methods: On the day of clinical suspicion of CRBSI, blood samples were obtained from the catheters for the AOLC test, and peripheral blood samples were obtained for quantitative blood cultures.

Calcitonin precursors in the prediction of severity of acute pancreatitis on the day of admission.

Background: Calcitonin precursors are sensitive markers of inflammation and infection. The aim of this study was to evaluate the role of plasma calcitonin precursor levels on the day of admission in the prediction of severity of acute pancreatitis, and to compare this with the Acute Physiology And Chronic Health Evaluation (APACHE) II scoring system.

Methods: Plasma concentrations of calcitonin precursors were determined on admission in 69 patients with acute pancreatitis.

DNA fingerprinting analysis of coagulase negative staphylococci implicated in catheter related bloodstream infections.

Aims: The epidemiological assessment of cases of coagulase negative staphylococcal catheter related bloodstream infection.

Methods: Two hundred and thirty patients with suspected catheter related bloodstream infection were evaluated over a two year period. Central venous catheters were cultured both endoluminally and extraluminally.

Enterococcal intravascular catheter-related bloodstream infection: management and outcome of 61 consecutive cases.

Enterococci are an increasingly important cause of intravascular catheter-related bloodstream infection (CRBSI), but the evidence base for treating such cases is limited. Successful antimicrobial treatment of CRBSI while leaving the central venous catheter (CVC) in situ has been reported for some bacteria, such as coagulase-negative staphylococci, but the effectiveness of this approach for treating enterococcal CRBSI is unknown. We aimed to determine the effectiveness of treatment options for enterococcal CRBSI and whether CVC removal is mandatory.

Endotoxin, cytokines and lipid peroxides in children with intussusception.

Background: Intussusception is a relatively common paediatric surgical emergency. The aim of this study was to investigate selected inflammatory mediators in children with acute intussusception and to identify potentially useful plasma markers of clinical outcome.

Methods: Clinical, radiographic, operative and pathological details were recorded prospectively of all children presenting to a single institution with a confirmed diagnosis of acute intussusception during 1 year.

In situ measurement of linezolid and vancomycin concentrations in intravascular catheter-associated biofilm.

We describe a new method for the measurement of antimicrobial concentrations in the biofilm associated with the endoluminal surface of intravascular catheters. We quantified endoluminal planktonic bacteria in haemodialysis catheters using the acridine orange method on catheter blood. After catheter removal, separate lumens were perfused in vitro with either vancomycin or linezolid to simulate in vivo antibiotic infusion.

Rapid diagnosis of central-venous-catheter-related bloodstream infection without catheter removal.

Background: Current methods for the diagnosis of bloodstream infection related to central venous catheters (CVC) are slow and in many cases require catheter removal. Since most CVC that are removed on suspicion of causing infection prove not to be infected, removal of catheters unnecessarily exposes patients to the risks associated with reinsertion.

Methods: The gram stain and acridine-orange leucocyte cytospin test (AOLC) is rapid (30 min), inexpensive, and requires only 100 microL catheter blood (treated with edetic acid) and the use of light and ultraviolet microscopy.

Evaluation of a novel endoluminal brush method for in situ diagnosis of catheter related sepsis.

Aims: To determine the accuracy of a novel endoluminal brush method for the diagnosis of catheter related sepsis (CRS), which is performed in situ and hence does not require line sacrifice.

Methods: 230 central venous catheters in 216 patients were examined prospectively for evidence of CRS or colonisation using an endoluminal brush method in conjunction with peripheral blood cultures. The results were compared with those obtained using methods that require line sacrifice: extraluminal sampling (Maki roll) or endoluminal sampling (modified Cleri flush) of microorganisms.

Rapid diagnosis of catheter-related sepsis using the acridine orange leukocyte cytospin test and an endoluminal brush.

Background: In neonates, the acridine orange leukocyte cytospin (AOLC) test has been found to be a highly sensitive test for the detection of infected i.v. catheters in situ, which provides a result in less than 1 hour.