The Insertion Site Should Be Considered for the Empirical Therapy of Short-Term Central Venous and Arterial Catheter-Related Infections.

OBJECTIVES: Little is known on causative pathogens of intravascular catheters infection according to the catheter insertion site. The present study aimed to describe the epidemiology of causative microorganisms of catheter-related infection and colonization according to the insertion site. DESIGN: Multicenter observational study using data from four large randomized controlled trials investigating different prevention strategies in which extensive prospective high-quality data collection at catheter insertion and catheter removal was performed. SETTING: Twenty-five ICUs in France. PATIENTS: Patients were recruited from 2006 to 2014 as soon as they required a catheterization with a short-term central venous catheter or peripheral arterial catheter with an expected duration of use of more than 48 hours. We described the distribution of microorganisms in central venous catheter and arterial catheter-related bloodstream infections and colonization according to the insertion type (femoral vs nonfemoral) included in the four studies. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 7,235 patients and 15,259 catheters were included. Among central venous catheter, the distribution of microorganisms associated with catheter-related bloodstream infection and colonization was significantly different between femoral and nonfemoral sites. Among central venous catheter catheter-related bloodstream infection, nonfermenting Gram-negative bacilli were more frequently detected at the femoral site (31% vs 4% for nonfemoral site; p < 0.01). After adjustment for confounding factors, the femoral site was still associated with an increased risk for catheter-related bloodstream infection due to nonfermenting Gram-negative bacilli (odds ratio, 6.33; 95% CI, 1.59-25.28; p < 0.01). Among colonized arterial catheters, the distribution of microorganisms was significantly different between femoral and radial site (p < 0.01). Colonized arterial catheters due to nonfermenting Gram-negative bacilli were more frequently observed at the femoral site (20% vs nonfemoral site 12%; p = 0.01). CONCLUSIONS: The proportion of intravascular catheter infections due to nonfermenting Gram-negative bacilli was high for the femoral insertion site. Empirical antipseudomonal therapy should be considered if a femoral catheter-related bloodstream infection is suspected.

Risk of Vascular Access Infection Associated With Buttonhole Cannulation of Fistulas: Data From the National Healthcare Safety Network.

RATIONALE & OBJECTIVE: Compared with conventional (rope-ladder cannulation [RLC]) methods, use of buttonhole cannulation (BHC) to access arteriovenous fistulas (AVFs) may be associated with increased risk for bloodstream infection and other vascular access-related infection. We used national surveillance data to evaluate the infection burden and risk among in-center hemodialysis patients with AVFs using BHC. STUDY DESIGN: Descriptive analysis of infections and related events and retrospective observational cohort study using National Healthcare Safety Network (NHSN) surveillance data. SETTING & PARTICIPANTS: US patients receiving hemodialysis treated in outpatient dialysis centers. PREDICTORS: AVF cannulation methods, dialysis facility characteristics, and infection control practices. OUTCOMES: Access-related bloodstream infection; local access-site infection; intravenous (IV) antimicrobial start. ANALYTIC APPROACH: Description of frequency and rate of infections; adjusted relative risk (aRR) for infection with BHC versus RLC estimated using Poisson regression. RESULTS: During 2013 to 2014, there were 2,466 access-related bloodstream infections, 3,169 local access-site infections, and 13,726 IV antimicrobial starts among patients accessed using BHC. Staphylococcus aureus was the most common pathogen, present in half (52%) of the BHC access-related bloodstream infections. Hospitalization was frequent among BHC access-related bloodstream infections (37%). In 2014, 9% (n=271,980) of all AVF patient-months reported to NHSN were associated with BHC. After adjusting for facility characteristics and practices, BHC was associated with significantly higher risk for access-related bloodstream infection (aRR, 2.6; 95% CI, 2.4-2.8) and local access-site infection (aRR, 1.5; 95% CI, 1.4-1.6) than RLC, but was not associated with increased risk for IV antimicrobial start. LIMITATIONS: Data for facility practices were self-reported and not patient specific. CONCLUSIONS: BHC was associated with higher risk for vascular access-related infection than RLC among in-center hemodialysis patients. Decisions regarding the use of BHC in dialysis centers should take into account the higher risk for infection. Studies are needed to evaluate infection control measures that may reduce infections related to BHC.

The Profile of Microorganisms Responsible for Port-Related Bacteremia in Pediatric Hemato-Oncological Patients.

Patients with pediatric cancer face an increased risk of infections. In most cases, these infections are associated with the use of a long-term central venous catheter. This study describes the epidemiology of a port-associated bacteremia as well as a profile of microorganisms responsible for port-associated bloodstream infections (PABSIs) in pediatric patients with cancer treated in a single center. The retrospective analysis included patients with cancer who had implanted a port, hospitalized between 2010 and 2015 at the Department of Pediatric Oncology, Hematology and Bone Marrow Transplantation, Poznan University of Medical Sciences. The medical records of patients were reviewed for demographic characteristics, diagnosis, port-related complications, and their management. Data were collected from patients' electronic medical records containing complete information on medical examinations and supplementary tests, diagnosis, timing, and type of port-associated complications. In a study period, 277 ports were inserted to 241 patients. A total of 183 094 catheter days were analyzed. Sixteen patients had more than 1 insertion of a port. The commonest observed complication was PABSI (40.07%) and the incidence density was 0.6 per 1000 port-days. Staphylococcus was the most commonly isolated organisms from patients with PABSI. From all port-associated complications, bloodstream infections and mechanical complications were the most often observed complications. The commonest pathogens responsible for PABSI were coagulase-negative staphylococci. Pathogens resistant to standard antibiotic treatment play an important role in PABSI, with methicillin-resistant Staphylococcus epidermidis being the predominant pathogen. Port-associated bloodstream infections are a common reason for preterm removal of a port.

Epidemiological features of nosocomial candidaemia in neonates, infants and children: A multicentre study in Iran.

Nosocomial bloodstream candidaemia is a life-threatening fungal infection with high morbidity and mortality, especially among paediatric patients undergoing intensive immunosuppressive therapy. Limited data on the epidemiology of candidaemia and susceptibility profiles are available for Iran. To characterise candidaemia epidemiology, comorbidity risk factors, species distribution, and antifungal susceptibility profiles among paediatric patients in Iran. This observational cross-sectional study enrolled 26 189 patients <18 years old at three reference paediatric hospitals in Mazandaran and Tehran over 2 years. Blood samples from patients with suspected fungal bloodstream infection were analysed using the BACTEC culture system. Fungal isolates were identified using matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF) and DNA sequencing. Antifungal susceptibility testing was performed using the Clinical and Laboratory Standards Institute broth microdilution guideline. We observed 109 episodes of nosocomial candidaemia in paediatric patients with or without immunosuppressive therapy. The most common healthcare-associated factor was central vascular catheter use (97%). The all-cause mortality rate was 40%, of which 48% was attributable to candidaemia. While Candida albicans was the most frequent causative agent (49%), emerging and uncommon Candida species were also isolated. Candidaemia mortality by non-albicans Candida species was significantly higher than that by C. albicans (P < .05). All fluconazole-resistant species were non-albicans Candida species. Uncommon Candida species with reduced susceptibility to antifungals are emerging as major agents of nosocomial candidaemia in high-risk paediatric patients in Iran. Appropriate source control, antifungal regimens and improved antifungal stewardship are warranted for managing and decreasing the burden of nosocomial candidaemia.

Dialysis access as a source of infective endocarditis in dialysis patients.

The incidence of Infective Endocarditis (IE) is higher in dialysis patients compared to the general population. A major risk factor for IE in this group stems from bacterial invasion during repeated vascular access. Previous studies have shown increased risk of bacteremia in patients with indwelling dialysis catheters compared to permanent vascular access. However, association between the development of IE and the type of dialysis access is unclear. We aimed to examine the associated types of intravascular access and route of infection in dialysis patients who were admitted with infective endocarditis at our center. All patients admitted to Albert Einstein Medical Center in Philadelphia with a diagnosis of infective endocarditis who were on chronic hemodialysis were identified from the hospital database for the period of 1/1/07 to 12/31/18. Modified Duke criteria was used to confirm the diagnosis of infective endocarditis. A total of 96 cases were identified. Of those, 57 patients had an indwelling dialysis catheter while the other 39 had permanent dialysis access. In 82% of patients with dialysis catheters, their dialysis access site was identified as the primary source of infection compared to 30% in those with permanent dialysis access (p<0.001). The number of dialysis catheters placed in the preceding 6 months was strongly associated with endocarditis resulting from the dialysis access site (OR = 3.202, p=0.025). Dialysis catheters are more likely to serve as the source of infection in dialysis patients developing IE compared to permanent dialysis access. Increased awareness of risk of IE associated with dialysis catheters is warranted.

Antibiotic locks for the treatment of catheter-related blood stream infection: Still more hope than data.

Antibiotic lock therapy (ALT), in conjunction with systemic antibiotics, is recommended by scientific societies as a treatment of uncomplicated catheter-related bloodstream infections (CRBSI) in hemodynamically stable hemodialysis patients for whom catheter salvage is the goal. The rationale for this strategy is the eradication of intraluminal biofilms by the highly concentrated antibiotic used in the lock. However, the available evidence supporting this recommendation is scanty, and only includes small, short-term, observational studies (most of them single-arm), with different definitions of CRBSI cure and variable follow-up periods. Furthermore, the ability of an antibiotic to eradicate a biofilm is not predicted by its inherent spectrum of antibacterial activity, since sessile microorganisms in their biofilm display other mechanisms of resistance to antibiotics than their planktonic counter-parts. Additionally, penetration of some antibiotics frequently used into biofilms produced by common microorganisms appears to be low. In this editorial we provide a critical view on the available evidence regarding the efficacy of ALT on the treatment of CRBSI in hemodialysis patients, as well as the microbiological issues and technical challenges of this strategy.

Survival of Staphylococcus epidermidis in Propofol and Intralipid in the Dead Space of Intravenous Injection Ports.

We tested whether propofol or Intralipid inoculated with Staphylococcus epidermidis would promote bacterial growth within an intravenous (IV) injection hub, a site prone to bacterial contamination. In tubes incubated under optimal conditions, S epidermidis exhibited growth in Intralipid, but not in propofol. In contrast, within the IV hub incubated with either propofol or intralipid at room temperature, S epidermidis bacterial numbers declined with time, and virtually no contamination remained after 12 hours. These data suggest that certain IV lines are inhospitable for S epidermidis.

Optimal vascular access strategies for patients receiving chemotherapy for early-stage breast cancer: a systematic review.

IMPORTANCE: Systemic chemotherapy can be administered either through a peripheral vein (IV), or centrally through peripherally inserted central catheter (PICC), totally implanted vascular access devices (PORTs) or tunnelled cuffed catheters. Despite the widespread use of systemic chemotherapy in patients with breast cancer, the optimal choice of vascular access is unknown. OBJECTIVE: This systematic review evaluated complication rates and patient satisfaction with different access strategies for administering neo/adjuvant chemotherapy for breast cancer. EVIDENCE REVIEWED: Ovid Medline, EMBASE and the Cochrane Central Register of Controlled Trials were searched from 1946 to September 2017. Two reviewers independently assessed each citation. The Newcastle-Ottawa scale was used to assess the quality of cohort and case-control studies. FINDINGS: Of 1584 citations identified, 15 unique studies met the pre-specified eligibility criteria. There were no randomised studies comparing types of vascular access. Reports included six single-institution retrospective cohort studies, one retrospective multi-institution cohort, one retrospective cohort database study, five prospective single-institution studies, one prospective multi-institution study and one nested case-control study. Median complication rates were infection: 6.0% PICC (2 studies) versus 2.1% PORT (8 studies); thrombosis: 8.9% PICC (2 studies) versus 2.6% PORT (9 studies); extravasation: 0 PICC (1 study) versus 0.4% PORT (4 studies) and mechanical issues: PICC 3.8% (1 study) versus 1.8% PORT (9 studies). Satisfaction/quality of life appeared high with each device. CONCLUSION: In the absence of high-quality data comparing vascular access strategies, randomised, adequately powered, prospective studies would be required to help inform clinical practice and reduce variation.

A Retrospective Analysis of Dialysis Events over a 3-Year Period in an Outpatient Dialysis Unit in the State of Kuwait.

OBJECTIVE: To determine the difference in the rates of dialysis events stratified by vascular access type and to describe the microbiological profile and sensitivity patterns of positive blood cultures over a 3-year period. SUBJECTS AND METHODS: The dialysis event data of 10,751 chronic hemodialysis patients collected from March 2013 to February 2016 at an outpatient dialysis unit in Kuwait were reviewed. The dialysis events studied were: intravenous (IV) antimicrobial use, a positive blood culture, and signs of inflammation at the vascular access site. Dialysis event rates were stratified by the type of vascular access used for the dialysis, i.e., fistula, graft, and tunneled/nontunneled central line. Rates were expressed per 100 patient-months. RESULTS: The overall dialysis event rate was (10.7/100 patient-months). The rate of IV antimicrobial use was higher (12.53/100 patient-months) in patients with tunneled central lines than in all other vascular access types (10.29/100 patient-months). Positive blood culture and inflammation at the vascular access site were highest in patients with nontunneled central lines (1.65 and 1.54/100 patient-months, respectively) when compared to those with other types of vascular access. Gram-negative rod isolates were predominant in patients with central lines (n = 35; 46.67%); however, common skin commensals and gram-negative rods were also identified in patients with fistula or graft (n = 4; 44.45%). CONCLUSION: Dialysis event rates were higher among patients with tunneled or nontunneled central lines than in patients with fistula or graft. Gram-negative rods were the most commonly isolated microbial group.

5-Hydroxyethyl-3-tetradecanoyltetramic acid represents a novel treatment for intravascular catheter infections due to Staphylococcus aureus.

Objectives: Biofilm infections of intravascular catheters caused by Staphylococcus aureus may be treated with catheter lock solutions (CLSs). Here we investigated the antibacterial activity, cytotoxicity and CLS potential of 5-hydroxyethyl-3-tetradecanoyltetramic acid (5HE-C14-TMA) compared with the related compounds 3-tetradecanoyltetronic (C14-TOA) and 3-tetradecanoylthiotetronic (C14-TTA), which are variants of quorum sensing signalling molecules produced by Pseudomonas aeruginosa . Methods: Antibacterial activity and mechanism of action of 5HE-C14-TMA, C14-TOA and C14-TTA were determined via MIC, bacterial killing, membrane potential and permeability assays. Susceptibility of S. aureus biofilms formed in the presence of plasma in vitro was investigated, MTT cytotoxicity testing was undertaken and cytokine release in human blood upon exposure to 5HE-C14-TMA and/or S. aureus biofilms was quantified. The effectiveness of 5HE-C14-TMA as CLS therapy in vivo was assessed using a rat intravascular catheter biofilm infection model. Results: MICs of 5HE-C14-TMA, C14-TOA and C14-TTA ranged from 2 to 4 mg/L. 5HE-C14-TMA and C14-TTA were bactericidal; all three compounds perturbed the staphylococcal membrane by increasing membrane permeability, depolarized the transmembrane potential and caused ATP leakage. Cytotoxicity and haemolytic activity were compound and target cell type-dependent. 5HE-C14-TMA reduced S. aureus biofilm viability in a dose-dependent manner in vitro and in vivo and did not trigger release of cytokines in human blood, but inhibited the high levels of IL-8 and TNF-α induced by S. aureus biofilms. Conclusions: 5HE-C14-TMA, C14-TOA and C14-TTA are membrane-active agents. 5HE-C14-TMA was the most potent, eradicating S. aureus biofilms at 512-1024 mg/L both in vitro and in vivo as a CLS.

Buttonhole Cannulation of the AV Fistula: A Critical Analysis of the Technique.

As a consequence of the central role of the arteriovenous fistula for dialysis (AVF) in the clinical management of the dialysis patient the necessity to limit the puncture-related complications to extend as much as possible the life of the vascular access. Accordingly, the AVF needling technique has gained growing attention. Alongside the traditional rope ladder (RL) puncture method, the buttonhole technique (BH) is increasingly popular; this technique employs the same cannulation sites of AVF in every dialysis associated with the use of dull needles to minimize vessels damage. The BH technique, utilized only for native AVF, is considered an appropriate alternative to the RL and is now recommended by several scientific societies for its reported benefits such as: AVF greater ease of cannulation, less pain, faster hemostasis and less tendency to the creation of aneurysms and hematomas. The use of BH is especially recommended in cases in which the RL is problematic with short or winding venous sections and in home dialysis in which the patient performs the needling. However recent evidence in literature, countering these theoretical advantages, indicates that the BH technique appears to be closely related to an increased risk of local and systemic infections. Furthermore, the purported benefits of BH have not held up under closer examination.

Water Soluble Vitamins Enhance the Growth of Microorganisms in Peripheral Parenteral Nutrition Solutions.

Peripheral parenteral nutrition (PPN) solutions contain amino acids, glucose, and electrolytes, with or without some water soluble vitamins. Peripheral venous catheters are one of the causes of catheter related blood stream infection (CRBSI), which requires infection control. In Japan, PPN solutions have rarely been prepared under aseptic conditions. However, in recent years, the necessity of adding vitamins to infusions has been reported. Therefore, we investigated the effects of water soluble vitamins on growth of microorganisms in PPN solutions. AMINOFLUID® (AF), BFLUID® (BF), PARESAFE® (PS) and PAREPLUS® (PP) PPN solutions were used. Water soluble vitamins contained in PP were also used. Causative microorganisms of CRBSI were used. Staphylococcus epidermidis decreased after 24 hours or 48 hours in all solutions. On the other hand, Escherichia coli, Serratia marcescens, Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans increased, especially in PP. When each water soluble vitamin was added to BF and PS, growth of S. aureus was greater in solutions that contained nicotinamide than in solutions that contained other vitamins. As for C. albicans, they grew in all test solutions. C. albicans grew especially well in solutions that contained biotin. When commercial amino acids and glucose solutions with electrolytes are administered, in particular those containing multivitamins or water soluble vitamins, efforts to control infection must be taken to prevent proliferation of microorganisms.

Host contributions to construction of three device-associated Candida albicans biofilms.

Among the most fascinating virulence attributes of Candida is the ability to transition to a biofilm lifestyle. As a biofilm, Candida cells adhere to a surface, such as a vascular catheter, and become encased in an extracellular matrix. During this mode of growth, Candida resists the normal immune response, often causing devastating disease. Based on scanning electron microscopy images, we hypothesized that host cells and proteins become incorporated into clinical biofilms. As a means to gain an understanding of these host-biofilm interactions, we explored biofilm-associated host components by using microscopy and liquid chromatography-mass spectrometry. Here we characterize the host proteins associated with several in vivo rat Candida albicans biofilms, including those from vascular catheter, denture, and urinary catheter models as well as uninfected devices. A conserved group of 14 host proteins were found to be more abundant during infection at each of the niches. The host proteins were leukocyte and erythrocyte associated and included proteins involved in inflammation, such as C-reactive protein, myeloperoxidase, and alarmin S100-A9. A group of 59 proteins were associated with both infected and uninfected devices, and these included matricellular and inflammatory proteins. In addition, site-specific proteins were identified, such as amylase in association with the denture device. Cellular analysis revealed neutrophils as the predominant leukocytes associating with biofilms. These experiments demonstrate that host cells and proteins are key components of in vivo Candida biofilms, likely with one subset associating with the device and another being recruited by the proliferating biofilm.

[Risk of bacteremia associated with intravascular devices stratified by birth weight in born of a public hospital of high complexity: follow-up to seven years]. / Riesgo de bacteriemia asociada a dispositivos intravasculares estratificados por peso de nacimiento en recién nacidos de un hospital público de alta complejidad: seguimiento de siete años.

INTRODUCTION: Bacteremia associated to vascular catheters is the most frequent nosocomial infection in Neonatal Intensive Care Units and increases cost and mortality. OBJECTIVE: To know the risk of bacteremia related to vascular devices in hospitalized newborns, stratified by birth weight. METHOD: A surveillance system was established considering birth weight and type of catheters in order to detect bacteremia and look for the risks associated to type of catheters and birth weight in the period 2005 to 2011, according to Chilean Ministry of Health's surveillance. RESULTS: We registered bacteremia associated to vascular devices in newborns considering birth weight between less than 1,000 g to more than 2,500 g from years 2005 and 2011. In the period, 4,704 patients were surveyed with 25,130 catheter days and 70 bacteremia were detected. The rates of bacteremia were 0.9 per 1,000 catheter days in peripheral catheters, 3.0 per 1000 catheter days in peripheral inserted central catheters and 9.6 per 1,000 catheter days in umbilical catheters (UC). On the other side the risk of bacteremia was 6.4% in newborns with birth weight less 1,000 g and 1.5% in newborns with birth weight over 2,500 g. Coagulase negative Staphylococcus was the most frequent isolate agents. CONCLUSIONS: The risk of developing bacteremia is associated with lower birth weight and the use of UC independent of weight.

What is the evidence for intraluminal colonization of hemodialysis catheters?

Hemodialysis catheter-related bloodstream infections are potentially devastating, leading to increased morbidity, mortality, and cost of care. Prospective studies published over the past 15 years shed light on the pathogenesis of these infections. The data suggest that the intraluminal microbial colonization of hemodialysis catheters often precedes bloodstream infection. This finding supports strategies aimed at preventing or eradicating intraluminal colonization.

Molecular investigation of bacterial communities on intravascular catheters: no longer just Staphylococcus.

Intravascular catheter-related bloodstream infections (IVC-BSIs) are associated with significant morbidity and mortality. Culture-independent molecular approaches can reveal and capture the composition of complex microbial communities, and are now being used to reveal "new" pathogens as well as the polymicrobial nature of some infections. Patients with concurrently sited arterial and central venous catheters who had clinically suspected IVC-BSIs, were examined by the high-throughput sequencing of microbial 16S rRNA. An average of 100 operational taxonomic units (OTUs, phylotypes) was observed on each IVC, indicating that IVCs were colonised by complex and diverse bacterial communities. Ralstonia (53 % of 16S rRNA sequences), Escherichia group (16 %), Propionibacterium (5 %), Staphylococcus (5 %), and Streptococcus (2 %) were the most abundant genera. There was no statistically significant difference in the bacterial communities examined from arterial and central venous catheters; from those with and without systemic antibiotic treatment; or from conventionally colonised and uncolonised IVCs. The genome of the predominant bacteria, R. pickettii AU12-08, was found to encode resistance to antimicrobial drugs of different classes. In addition, many encoded gene products are involved in quorum sensing and biofilm formation that would further contribute to increased antimicrobial drug resistance. Our results highlight the complex diversity of microbial ecosystems on vascular devices. High-throughput sequencing of 16S rRNA offers an insight into the pathogenesis of IVC-related infections, and opens up the scope for improving diagnosis and patient management.

Totally implantable vascular access devices 30 years after the first procedure. What has changed and what is still unsolved?

The first placement of a totally implantable central venous access device (TIVAD) was performed in 1982 at the MD Anderson Cancer Center in Houston by John Niederhuber, using the cephalic vein­exposed by surgical cut-down­as route of access to central veins. After that, TIVADs proved to be safe and effective for repeated administration of drugs, blood, nutrients,and blood drawing for testing in many clinical settings, especially in the oncologic applications. They allow for administration of hyperosmolar solutions, extreme pH drugs, and vescicant chemotherapeutic agents,thus improving venous access reliability and overall patients' quality of life. Despite the availability of a variety of devices, each showing different features and performances, many issues are still unsolved. The aim of this review article is to point out what has changed since the first implant of a TIVAD, and what it is still matter of debate, thus needing more investigation. Topics analyzed here include materials, choice of the veins and techniques of implantation, role of ultrasound (US) guidance in central venous access, position of catheter tip assessment, TIVAD-related infection and thrombosis, and quality of life issues.

Preventing catheter-related bacteremia with taurolidine-citrate catheter locks: a systematic review and meta-analysis.

BACKGROUND: Preliminary evidence from some studies suggests that taurolidine-citrate locks decrease catheter-related bacteremia (CRB), which is a major cause of morbidity and mortality in patients using intravascular catheters. No previous study has sought to summarize existing evidence on the use of taurolidine-citrate locks. A systematic review and meta-analysis were undertaken to determine whether taurolidine-citrate was more effective than heparin in the prevention of CRB. METHODS: The major English (PubMed, EBSCO, Web of Science and OVID) and Chinese (CBM, CNKI, VIP and Wanfang Data) healthcare databases were searched for randomized controlled trials comparing the efficacy and safety of taurolidine-citrate lock solution (TCLS) and heparin lock solution in the prevention of CRB. RESULTS: Three studies involving 236 patients with a total of 34,984 catheter days were included. The use of TCLS significantly decreased the risk of CRB (relative risk = 0.47, 95% CI: 0.25-0.89) and Gram-negative bacterial infection. There was no significant difference in Gram-positive infections and exit-site infections. CONCLUSIONS: Catheter locking with TCLS reduced the risk of CRB and Gram-negative bacterial infection. Adverse events include thrombotic events.

Can MALDI-TOF mass spectrometry be used with intravascular catheters?

INTRODUCTION: The use of the matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry has shown to be effective and fast in some clinical specimens for the identification of colonizing microorganisms. The objective of the study was to analyze the validity values for the prediction of colonization and catheter-related bloodstream infection (C-RBSI) of the MALDI-TOF mass spectrometry performed at all intravascular catheters that arrived in the microbiology laboratory. METHODS: Catheter tips (after performing the roll-plate technique) were tested by MALDI-TOF mass spectrometry during a period of 3-months. The gold standard for colonization and C-RBSI were, respectively: the presence of ≥15cfu/plate in the catheter tip culture; and the isolation of the same microorganism(s) in blood cultures as well as in the colonized catheter (during the 7days before or after catheter withdrawal). RESULTS: A total of 182 intravascular catheters were collected. The overall colonization rate detected by roll-plate technique and MAL-TOF mass spectrometry was 31.9% and 32.4%, respectively. Overall, there were 33 (18.1%) episodes of C-RBSI. The validity values of the MALDI-TOF mass spectrometry for the identification of colonization and C-RBSI were, respectively: sensitivity (69.0%/66.7%), specificity (84.7%/75.2%), positive predictive value (65.6%/36.1%), and negative predictive value (86.8%/92.6%). Conclusion MALDI-TOF mass spectrometry could be an alternative diagnostic tool for ruling out C-RBSI. However, despite it showing to be faster than conventional culture, future studies are required in order to improve the pre-analytical process.

Central vascular catheter infections in a Hospital of Central Italy.

The insertion and the permanence of central venous catheters (CVC) represent potential sources of infection contracted in hospital. The evaluation of the risk of CVC-associated infections was evaluated in a retrospective study during the period 2007-2010 in a Hospital of Central Italy. A total of 514 CVC were collected and examined by microbiological techniques and, among the examined patients, 450 CVC blood cultures were collected. Cultures were performed collecting a portion of 5-6 cm of intravenous catheters in liquid medium and spread on selective media for Gram-positive and Gram-negative bacteria and yeasts; blood specimens were obtained through peripheral venous punctures and analyzed by a commercial automated system. 308/514 (59.90%) samples were positive to the microbiological culture. Staphylococcus aureus, S. epidermidis and other coagulase negative Staphylococci (CNS) were the prevalent Gram-positive bacteria. Among Gram-negative bacteria, Enterobacteriaceae and Pseudomonaceae were the main bacteria isolated. A higher prevalence of Gram-positive bacteria was observed in Neonatal Pathology (90.90%). The Intensive Care Unit (ICU) showed 73.10% of positive cultures with 54.12% of Gram-positive isolates. Among positive blood cultures (38%), Gram-positive bacteria were the main bacteria isolated. The high prevalence of catheter-related infections requires accurate surveillance and the assumption of preventive measures in particular during catheter insertion.