(1) Background: The discrepant antimicrobial susceptibility between planktonic and biofilm bacterial modes poses a problem for clinical microbiology laboratories and necessitates a relevant 3D experimental model allowing bacteria to grow in biofilm mode, in vitro, for use in anti-biofilm susceptibility testing. (2) Methods: This work develops a 3D biofilm model consisting of alginate beads containing biofilm and encased within two thick layers of alginate matrix. The constructed model was placed on a thin Boyden chamber insert suspended on a 24-well culture plate containing the culture medium.
View Article and Find Full Text PDFIntroduction: Peritoneal dialysis (PD) is a widely used dialysis modality, which offers the advantage of being a home therapy but is associated with a risk of potentially serious infections, including exit site infection, catheter tunnel infection, and peritonitis that may result in morbidity, technique failure, and increased mortality. Catheters impregnated with antimicrobials hold promise as a novel technique to reduce PD associated infections.
Areas Covered: We describe PD modalities, catheters, technique, complications, and the microbiology of associated infections, as well as standard measures to reduce the risk of infection.
Self-targeting antimicrobial platforms have yielded new possibilities for the treatment of infectious biofilms. Self-targeting involves stealth transport through the blood circulation towards an infectious biofilm, where the antimicrobial platform penetrates and accumulates in a biofilm in response to a change in environmental conditions, such as local pH. In a final step, nano-antimicrobials need to be activated or the antimicrobial cargo of nanocarriers released.
View Article and Find Full Text PDFAll implants are rapidly coated by the host with glycoproteins forming a thin capsule, and this is a normal response. Where an inflammatory stimulus such as infection is present, the capsule can thicken and become microvascularised and sometimes calcified. This inflammatory stimulus can take the form of leachable chemicals from the implant, or bacteria live or dead.
View Article and Find Full Text PDFBackground: The first step in bundle design or implementation is to identify the problem being addressed. Several validated approaches are recommended to facilitate this. These include using systematic reviews, adverse event triggers and risk assessment tools.
View Article and Find Full Text PDFThe rising occurrence of antimicrobial resistance demands new strategies for delivering antibiotics to ensure their effective use. In this study, a multi-functional strategy to address medical device associated infections is explored whereby an anti-attachment and an antibacterial mechanism have been combined. Silicone catheters impregnated with multiple antibiotics are coated with polyacrylate coatings previously shown to reduce bacterial attachment and biofilm formation.
View Article and Find Full Text PDFBackground: Hydrocephalus is managed by surgically implanting flow-diversion technologies such as differential pressure valves and antisiphoning devices; however, such hardware is prone to failure. Extensive research has tested them in flow-controlled settings using saline or de-aerated water, yet little has been done to validate their performance in a setting recreating physiologically relevant parameters, including intracranial pressures, cerebrospinal fluid (CSF) protein content, and body position.
Objective: To more accurately chart the episodic drainage characteristics of flow-diversion technology.
False negative culture results in periprosthetic joint infection (PJI) are not uncommon particularly when patients have received long term antibiotics. Polymerase chain reaction (PCR) has a lower specificity partly due to detection of residual DNA from dead bacteria. Propidium monoazide (PMA) prevents DNA from dead bacteria from being amplified during the PCR.
View Article and Find Full Text PDFAmniotic membrane (AM) is used to treat a range of ophthalmic indications but must be presented in a non-contaminated state. AM from elective caesarean sections contains natural microbial contamination, requiring removal during processing protocols. The aim of this study was to assess the ability of antibiotic decontamination of AM, during processing by innovative low-temperature vacuum-drying.
View Article and Find Full Text PDFBackground: External ventricular drainage (EVD) carries a high risk of ventriculitis, increasingly caused by MDR Gram-negative bacteria such as Escherichia coli and Acinetobacter baumannii. Existing antimicrobial EVD catheters are not effective against these, and we have developed a catheter with activity against MDR bacteria and demonstrated the safety of the new formulation for use in the brain.
Objectives: Our aim was to determine the ability of a newly formulated impregnated EVD catheters to withstand challenge with MDR Gram-negative bacteria and to obtain information about its safety for use in the CNS.
Two major complications of indwelling urinary catheterisation include infection and mineral encrustation of the catheter. Our antimicrobial urinary catheter (AUC) impregnated with rifampicin, triclosan, and sparfloxacin has demonstrated long-term protective activity against major uropathogens. This study aimed to firstly assess the ability of the AUC to resist mineral encrustation in the presence and absence of bacteria.
View Article and Find Full Text PDFTo determine micro-organisms attached to removed urethral catheters and relate this to patient-specific information. Indwelling urethral catheters were collected from patients at a UK teaching hospital. The balloon and lumen were sonicated, and micro-organisms were enumerated.
View Article and Find Full Text PDFCurrent regulatory requirements impede clinical translation and market introduction of many new antimicrobial combination implants and devices, causing unnecessary patient suffering, doctor frustration, and costs to healthcare payers. Regulatory requirements of antimicrobial combination implants and devices should be thoroughly revisited and their approval allowed based on enrichment of benefit demonstrations from high-risk patient groups and populations or device components to facilitate their clinical translation. Biomaterial implant and devices equipped with antimicrobial strategies and approved based on enrichment claims should be mandatorily enrolled in global registry studies supervised by regulatory agencies for a minimum five-year period or until statistically validated evidence for noninferiority or superiority of claims is demonstrated.
View Article and Find Full Text PDFEur J Clin Microbiol Infect Dis
January 2019
Tissues are valuable microbiological samples that have proved superiority over swabs. Culture of tissue samples is used in the diagnosis of a variety of infections. However, as well as factors such as the site of obtaining the sample, the number of samples, and previous antibiotic use, the method of tissue processing may have an important effect on sensitivity.
View Article and Find Full Text PDFAims: We have developed a novel antimicrobial urinary catheter (AUC) impregnated with rifampicin, triclosan, and sparfloxacin and demonstrated that it has long-term (∼84 days) protection against bacterial colonization in vitro. This study aimed to assess the safety and patient acceptability of this device in long-term catheter users.
Methods: Adults who use long term (>28 days) indwelling urinary catheters with capacity to consent were invited to receive the AUC at their next catheter change.
Prosthetic joint infection is usually caused by staphylococci. Among the coagulase-negative staphylococci, is important because it behaves as a pathogen similar to . It also develops biofilms, and the biofilm phenotype can appear as small-colony variants.
View Article and Find Full Text PDFInfections associated with percutaneous pins and wires are common complications which can have a significant impact on patient outcomes. A survey was undertaken to identify current practice and gain insight into variations of clinical practice. Invitations were sent by email to complete an electronic questionnaire using SurveyMonkey.
View Article and Find Full Text PDFJ Neurol Neurosurg Psychiatry
February 2018
Objectives: External ventricular drain (EVD) insertion is a common neurosurgical procedure. EVD-related infection (ERI) is a major complication that can lead to morbidity and mortality. In this study, we aimed to establish a national ERI rate in the UK and Ireland and determine key factors influencing the infection risk.
View Article and Find Full Text PDFObjectives: To evaluate potential anti-biofilm agents for their ability to enhance the activity of antibiotics for local treatment of localized biofilm infections.
Methods: Staphylococcus aureus and Pseudomonas aeruginosa in vitro biofilm models were developed. The putative antibiotic enhancers N-acetylcysteine, acetylsalicylic acid, sodium salicylate, recombinant human deoxyribonuclease I, dispersin B, hydrogen peroxide and Johnson's Baby Shampoo (JBS) were tested for their anti-biofilm activity alone and their ability to enhance the activity of antibiotics for 7 or 14 days, against 5 day old biofilms.
Background: The insertion of external ventricular drains (EVDs) is necessary in some neurosurgical patients, but increases the risk of meningitis/ventriculitis. While there are well-recognized risk factors, the proportion of patients who develop meningitis/ventriculitis varies partly due to differences in definitions. A multi-disciplinary working group was established to agree definitions for EVD-associated meningitis/ventriculitis, and a surveillance system was piloted in four centres in the UK and Ireland.
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