Clinical practice guidelines for the diagnosis and management of intravascular catheter-related infection: 2009 Update by the Infectious Diseases Society of America

Are bloodstream leukocytes Trojan Horses for the metastasis of Staphylococcus aureus?

Staphylococcus aureus bacteraemia remains very difficult to treat, and a large proportion of cases result in potentially lethal metastatic infection. Unpredictable and persistent bacteraemia in the face of highly active, usually bactericidal antibiotics is the strongest predictor of death or disseminated disease. Although S. aureus has conventionally been considered an extracellular pathogen, much evidence demonstrates that it can survive intracellularly. In this Opinion article, we propose that phagocytes, and specifically neutrophils, represent a privileged site for S. aureus in the bloodstream, offering protection from most antibiotics and providing a mechanism by which the bacterium can travel to and infect distant sites. Furthermore, we suggest how this can be experimentally confirmed and how it may prompt a change in the current paradigm of S. aureus bacteraemia and identify better treatment options for improved clinical outcomes.

Nosocomial infections and multidrug-resistant bacterial organisms in the pediatric intensive care unit

Nosocomial infections in Pediatric Intensive Care Units (PICUs) caused by multidrug-resistant bacterial organisms are increasing. This review attempts to report on significant findings in the current literature related to nosocomial infections in PICU settings with an international perspective. The types of nosocomial infections are addressed, including catheter-related bloodstream infections, ventilator-associated pneumonia, urinary tract infections, gastrointestinal infections and post-surgical wound infections. A review of emerging resistant bacterial pathogens includes methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus sp., Clostridium difficile, extended-spectrum β-lactamase producing Gram-negative organisms, Klebsiella pneumoniae carbapenemase-producing strains and multi-drug resistant Acinetobacter baumannii. Basic and enhanced infection control methods for the management and control of multidrug-resistant organisms are also summarized with an emphasis on prevention.

Invasive candidiasis in non-hematological patients

Candida is one of the most frequent pathogens isolated in bloodstream infections, and is associated with significant morbidity and mortality. In addition to haematological patients, there are several other populations with a substantial risk of developing invasive candidiasis (IC). These include patients undergoing prolonged hospitalisation with the use of broad-spectrum antibiotics, those fitted with intravascular catheters, admitted to both adult and neonate intensive care units (ICU) or gastrointestinal surgery wards and subjects with solid tumours undergoing cytotoxic chemotherapy. As a general rule, every immunocompromised patient might be at risk of Candida infection, including, for example, diabetic patients.

The epidemiology of species responsible for IC has been changing, both at local and worldwide level, shifting from C. albicans to non-albicans species, that can be intrinsically resistant to fluconazole (C. krusei and, to some extent, C. glabrata), difficult to eradicate because of biofilm production (C. parapsilosis) or than might acquire resistance to azole during therapy.

Delaying the specific therapy has been shown to increase morbidity and mortality, but traditional microbiological diagnosis is poorly sensitive and slow. Thus, culture-based treatment may result in therapy started too late. In order to reduce the mortality in IC, several management strategies have been developed: prophylaxis, empirical and pre-emptive therapy. Compared to prophylaxis, the latter approaches allow to reduce the use of antifungals by targeting only patients at very high risk of IC. Non-invasive serological markers and scores based on clinical prediction rules such as the presence of risk factors or Candida colonisation, have been developed with the aim of allowing prompt initiation of treatment. Although the use of these diagnostic tools in pre-emptive strategies is promising, the performance and cost-effectiveness should be tested in large trials.

Agents recommended for initial treatment of candidemia in severely ill patients include echinocandins and lipid formulations of amphotericin B, while stable patients without risk factors for azole-resistance might be treated with fluconazole.

Clinical experience with daptomycin in Europe: the first 2.5 years

Objectives

To describe the patient populations and infections being treated with daptomycin, as well as the efficacy and safety outcomes.

Patients and methods

Data from the European Cubicin Outcomes Registry and Experience (EU-CORE^SM), retrospectively collected at 118 institutions between January 2006 and August 2008, were analysed.

Results

Daptomycin treatment was documented in 1127 patients with diverse infections, including complicated skin and soft tissue infections (33%), bacteraemia (22%), endocarditis (12%) and osteomyelitis (6%). It was used empirically, before microbiological results became available, in 53% of patients. Staphylococcus aureus was the most common pathogen (34%), with 52% of isolates resistant to methicillin; coagulase-negative staphylococci and enterococci were also frequent, with 22% of Enterococcus faecium isolates resistant to vancomycin. Daptomycin was used as first-line therapy in 302 (27%) patients. When used second line, the most common reasons for discontinuation of previous antibiotic were treatment failure and toxicity or intolerance. The use of concomitant antibiotics was reported in 65% of patients. Most frequent doses were 6 mg/kg (47%) and 4 mg/kg (32%). The median duration of daptomycin therapy was 10 days (range 1–246 days) in the inpatient setting and 13 days (range 2–189 days) in the outpatient setting. The overall clinical success rate was 79%, with a clinical failure rate of <10% for all infection types. Low failure rates were observed in first- and second-line therapy (6% and 8%, respectively). Daptomycin demonstrated a favourable safety and tolerability profile regardless of treatment duration.

Conclusions

Daptomycin has a relevant role in the treatment of Gram-positive infections.

Treatment of Long-Term Catheter-Related Bloodstream Infections with a Taurolidine Block: A Single Cancer Center Experience

Purpose

Catheter-related bloodstream infections (CRBSIs) are a common problem in cancer patients with long-term catheters. The effectiveness of taurolidine, a new antimicrobial solution, in the management of CRBSIs is still unknown. A retrospective analysis of patients with proven CRBSIs treated with a taurolidine block in combination with systemic antibiotic treatment was performed to define its role in the management of CRBSIs.

Methods

Twenty-four episodes of CRBSIs in 23 cancer patients with permanent use of the long-term catheter were treated with a taurolidine block for 3 consecutive days in combination with systemic antibiotic treatment.

Results

Treatment was successful in 16 of 24 events (67%). Explantation was performed in 8 cases (33%): in 3 patients due to a second positive blood culture, and in 1 patient due to recurrent fever after the conservative treatment. In 4 patients, the conservative approach was prematurely stopped due to persisting fever.

Conclusion

Taurolidine-based treatment may be a promising, noninvasive therapeutical approach in the management of long-term catheter-related bloodstream infections in cancer patients.

How I manage haematology patients with septic shock

Patients with a variety of haematological conditions are at risk of infection and its most serious complication: septic shock. Mortality for septic shock remains high and especially so in patients with haematological malignancy and following bone marrow transplantation. However, advances in the treatment of severe sepsis have improved mortality rates even though evidence for the management of severe sepsis in haematology patients is limited. Wherever possible this review will concentrate on evidence directly applicable to haematology patients but inevitably will have to extrapolate evidence from other patient groups. The Surviving Sepsis Guidelines 2008 provide information on best practice in the management of patients with severe sepsis and septic shock and are broadly applicable though not specific to haematology patients. This review summarizes a practical approach to the management of severe sepsis in haematology patients and highlights areas of research which may bring new treatments in the future. The review is limited to the management and initial resuscitation of septic shock in adult haematology patients and will not address the detailed intensive care management of these patients or the management of severe sepsis in children.

An outbreak of Mycobacterium mucogenicum bacteremia in pediatric hematology-oncology patients

BACKGROUND AND AIMS

Mycobacterium mucogenicum (MM) is a rapidly growing nontuberculous mycobacterium that is commonly identified in tap water that can rarely cause bacteremia. We describe an outbreak of MM bacteremia among pediatric hematology-oncology patients.

METHODS

Charts of children with MM bacteremia were retrospectively reviewed. Demographic data, underlying conditions, central venous catheter (CVC) type, duration of bacteremia, and treatment were retrieved. Epidemiologic investigation was conducted during the outbreak including environmental sampling.

RESULTS

During an 8-month period (September 2005-May 2006), 8 patients aged 1.5 to 17 years had MM bacteremia. Seven patients had underlying malignancy and 1 with thalassemia major had bone marrow transplantation. The mean number of positive blood cultures was 4.2 (1-11) per patient. Two patients received antibiotic treatment in addition to removal of CVC. All patients were cured. Almost 60 environmental samples were obtained from surfaces, ice, and municipal water supply. All were negative and no source was documented. Infection control measures included emphasis on guidelines for prevention of CVC-associated infections. No cases occurred before and after this outbreak.

CONCLUSIONS

MM is a rare agent of CVC-associated bacteremia. Removal of the CVC may be sufficient for management of bacteremia. In the absence of definite source identification, reinforcement of standard infection control measures can be successful in containing outbreaks.

A seven-year survey of management of coagulase-negative staphylococcal sepsis in the neonatal intensive care unit: vancomycin may not be necessary as empiric therapy

BACKGROUND

The typical empiric therapy for coagulase-negative staphylococcal (CONS) sepsis includes vancomycin. In our neonatal intensive care unit, we have consistently avoided the use of vancomycin to treat CONS sepsis, except for specific cases, and have used instead cefazolin as empiric agent.

OBJECTIVES

The clinical outcome of infants with CONS sepsis was evaluated in relation to the susceptibility of CONS blood isolates to cefazolin over a period of 7 years.

METHODS

Clinical characteristics, symptoms of sepsis and antibiotic use were studied retrospectively. Susceptibility of CONS blood isolates to cefazolin was determined by E-test.

RESULTS

Of 163 infants with proven CONS sepsis, 121/140 (86%) infants with a cefazolin-susceptible (minimum inhibition concentration (MIC) ≤8 mg/l) and 21/23 (91%) with a cefazolin-resistant (MIC ≥32 mg/l) blood isolate were treated with cefazolin. 21 (13%) infants were switched to vancomycin, in only 3 of them CONS had become resistant to cefazolin. The majority (81%) of the infants with a good response to cefazolin had the indwelling central venous catheter removed, in contrast to only 22% of the infants with cefazolin treatment failure. Median cefazolin MIC values were 0.75-2 mg/l during the study period.

CONCLUSIONS

The great majority of infants with CONS sepsis was successfully treated with cefazolin. The use of vancomycin could be restricted to specific cases. Despite the consistent use of cefazolin in neonatal CONS sepsis over an extended period of time, cefazolin MIC values remained low and in the susceptible range. Removal of the central venous catheter in infants with clinical symptoms of sepsis is an important therapeutic measure.

Anti-infective locks for treatment of central line-associated bloodstream infection: a systematic review and meta-analysis

Central line-associated bloodstream infections (CLABSI) are associated with considerable morbidity, mortality and economic costs. In most cases, catheter removal is considered an essential component of managing CLABSI. However, in patients with poor access, catheter salvage may have to be attempted rather than removal and replacement of catheters. Anti-infective lock therapy (ALT) - instilling an antibiotic or antiseptic into the catheter lumen - is a novel way of treating CLABSI while attempting to salvage the catheter. However, data on the efficacy of ALT for catheter salvage is limited. In this systematic review, we critically review the evidence regarding the use of ALT for catheter salvage. We identified 8 studies including a total of 396 patients that compared ALT with systemic antibiotic therapy alone or an alternate method of catheter salvage (guidewire replacement). We found that the combination of systemic antibiotics and culture-guided lock therapy was superior to systemic antibiotics alone (OR: 0.20, 95% CI: 0.10-0.39), with 10% of locked patients requiring replacement compared to 33% of subjects without locks. There was a 20% relapse rate in the ALT group and a 30% relapse rate in the control group (OR: 0.43, 95% CI: 0.18-1.03). There was insufficient data on catheter exchange over a wire compared with ALT to permit conclusions. Our data support the use of ALT in conjunction with systemic antibiotics for catheter salvage. Large randomized controlled trials of ALT examining dose, dwell times and relapse rates stratified by infecting pathogen are needed.

Clinical outcome of catheter salvage in neutropenic cancer patients with catheter-related infection

BACKGROUND

Catheter-related infections (CRI) cause significant morbidity and mortality in cancer patients, particularly during episodes of chemotherapy-induced neutropenia. This study was performed to evaluate clinical features and outcomes of CRI in neutropenic cancer patients.

METHODS

We retrospectively analyzed clinical characteristics and outcome of febrile neutropenic cancer patients with CRI who visited the emergency department from January 1996 to June 2007.

RESULTS

A total of 51 neutropenic cancer patients with CRI were identified and 53 organisms were isolated from culture specimens. The mean ± standard deviation patient age was 50 ± 15 y and the most common underlying disease was lymphoma (n = 27, 53%). Gram-positive organisms accounted for 77% of all isolated pathogens (41/53). Initial catheter salvage was attempted in 38 episodes of CRI, of which 20 were successful. In the current study the overall success rate of catheter salvage attempts was 52.6%. The failure rate of catheter salvage was significantly higher in CRI caused by Gram-negative pathogens than by Gram-positive pathogens.

CONCLUSION

Although catheter salvage should be cautiously attempted for cancer patients with CRI, it might not be a treatment option for neutropenic cancer patients with CRI caused by Gram-negative bacteria.

Novel approach using antimicrobial catheters to improve the management of central line-associated bloodstream infections in cancer patients

BACKGROUND

Central venous catheter (CVC) removal has often been recommended for the treatment of central line-associated bloodstream infections (CLABSIs). However, CVC removal is not always practical in patients with cancer, and changing CVCs with noncoated CVCs over guidewire may result in cross-infection of the new CVC. Therefore, the current matched retrospective cohort study was conducted to evaluate the effectiveness of exchanging infected CVCs for minocycline- and rifampin (MR)-coated CVCs in cancer patients with CLABSIs.

METHODS

The authors identified all cancer patients with CLABSIs who had undergone either CVC exchange with MR-coated CVCs or CVC removal at the study institution. All patients were treated with appropriate systemic antibiotics. The exchange group was matched in a 1:2 ratio with the removal group by organism, underlying disease, and neutropenia. The demographics, clinical characteristics, and outcome were compared. Overall response was defined as the resolution of clinical signs and symptoms and eradication of bacteremia within 72 hours after CVC exchange or removal, without disease recurrence or infection-related death.

RESULTS

A total of 120 cancer patients were included (40 in the exchange group and 80 in the removal group). Overall response rates were 95% in the exchange group and 76% in the removal group (P = .011). No disease recurrences or infection-related deaths occurred in the exchange group; 8 disease recurrences or deaths (11%) occurred in the removal group (P = .05). Patients in the exchange group also experienced lower rates of mechanical failure (3% vs 15%; P = .049).

CONCLUSIONS

Exchanging CVCs for MR-coated CVCs in cancer patients with CLABSIs may improve the overall response rate and decrease the risk of mechanical failure, disease recurrence, and infection-related mortality.

The management of Staphylococcus aureus bacteremia in the United Kingdom and Vietnam: a multi-centre evaluation

Background

Staphylococcus aureus bacteremia is a common and serious infection worldwide and although treatment guidelines exist, there is little consensus on optimal management. In this study we assessed the variation in management and adherence to treatment guidelines of S. aureus bacteremia.

Methodology/Principal Findings

We prospectively recorded baseline clinical characteristics, management, and in-hospital outcome of all adults with S. aureus bacteremia treated consecutively over one year in eight centres in the United Kingdom, three in Vietnam and one in Nepal. 630 adults were treated for S. aureus bacteremia: 549 in the UK (21% methicillin-resistant), 80 in Vietnam (19% methicillin-resistant) and 1 in Nepal. In the UK, 41% had a removable infection focus (50% intravenous catheter-related), compared to 12% in Vietnam. Significantly (p<0.001) higher proportions of UK than Vietnamese patients had an echocardiogram (50% versus 28%), received more than 14 days antibiotic therapy (84% versus 44%), and received >50% of treatment with oral antibiotics alone (25% versus 4%). UK centres varied significantly (p<0.01) in the proportions given oral treatment alone for >50% of treatment (range 12–40%), in those treated for longer than 28 days (range 13–54%), and in those given combination therapy (range 14–94%). 24% died during admission: older age, time in hospital before bacteremia, and an unidentified infection focus were independent predictors of in-hospital death (p<0.001).

Conclusions/Significance

The management of S. aureus bacteremia varies widely between the UK and Vietnam and between centres in the UK with little adherence to published guidelines. Controlled trials defining optimal therapy are urgently required.

[Impact of primary and intravascular catheter-related bacteremia due to coagulase-negative staphylococci in critically ill patients]

OBJECTIVE

To study the impact of coagulase-negative staphylococcal (CNS) primary and intravascular catheter-related bloodstream infection (PBSI/CRBSI) on mortality and morbidity in critically-ill patients.

DESIGN

We performed a double analysis using data from the ENVIN-HELICS registry data (years 1997 to 2008): 1) We studied the clinical characteristics and outcomes of patients with CNS-induced PBSI/CRBSI and compared them with those of patients with PBSI/CRBSI caused by other pathogens; and 2) We analyzed the impact of CNS-induced PBSI/CRBSI using a case-control design (1:4) in patients without other nosocomial infections.

SETTING

167 Spanish Intensive Care Units.

PATIENTS

Patients admitted to ICU for more than 24 hours.

RESULTS

2,252 patients developed PBSI/CRBSI, of which 1,133 were caused by CNS. The associated mortality for PBSI/CRBSI caused by non-CNS pathogens was higher than that of the CNS group (29.8% vs. 25.9%; P=.039) due exclusively to the mortality of patients with candidemia (mortality: 45.9%). In patients without other infections, PBSI/CRBSI caused by CNS (414 patients) is an independent risk factor for a higher than average length of ICU stay (OR: 5.81, 95% CI: 4.31-7.82; P<.001).

CONCLUSION

Crude mortality of patients with CNS-induced BPSI/CRBSI is similar to that of patients with BPSI/CRBSI caused by other bacteria, but lower than that of patients with candidemia. Compared to patients without nosocomial infections, CNS-induced PBSI/CRBSI is associated with a significant increase in length of ICU stay.

Catheter-related bloodstream infections: catheter management according to pathogen

Central-line access is an essential part of modern healthcare practice; however, catheter-related bloodstream infection is a major problem that causes substantial morbidity and mortality, and excess length of stay and cost. The risk of infection depends on the type of device, the site of insertion, the underlying conditions and the appropriate prevention measures taken during catheter insertion. Management of catheter-related bloodstream infection involves deciding on catheter removal, antimicrobial catheter lock solution and the type and duration of systemic antimicrobial therapy. Systemic antimicrobial use is essential but, although generally effective in controlling sepsis, it often fails to sterilise the line, increasing the incidence of complications or recurrence. The decision regarding whether the catheter should be removed or retained is therefore crucial. One of the major factors to be considered is the type of organism involved in the catheter-related infection. This review outlines the epidemiology, pathogenesis, diagnosis, microbiology and management of catheter-related infections, mainly focusing on the management of the intravascular device according to the pathogen.

Equipe interdisciplinar reduz infecção sanguínea relacionada ao cateter venoso central em Unidade de Terapia Intensiva Pediátrica

OBJETIVO: Avaliar o impacto de intervenções interdisciplinares nos indicadores de infecção de corrente sanguínea relacionada ao cateter venoso central e microrganismos isolados, em uma Unidade de Terapia Intensiva Pediátrica. MÉTODOS: Estudo de intervenção do tipo antes e depois. Foi criado um programa educativo e constituída uma equipe interdisciplinar de intervenção composta por médicos e enfermeiros da unidade e do Serviço de Controle de Infecção Hospitalar. As intervenções foram compostas por medidas diretas e indiretas educativas e processuais. O período pré-intervenção (Fase 1), de junho de 2003 a maio de 2004, foi comparado ao período pós-intervenção nas Fases 2 (junho de 2004 a maio de 2005) e 3 (junho de 2005 a maio de 2006). As taxas de infecção foram comparadas por ANOVA, sendo significante p<0,05. RESULTADOS: Foram avaliados 1.234 pacientes entre 1º de junho de 2003 e 31 de maio de 2006. A densidade de incidência de infecção de corrente sanguínea relacionada ao cateter venoso central foi de 22,72 por 1.000 dias de cateter na Fase 1; diminuiu para 6,81 e 5,87 nas Fases 2 e 3, respectivamente (p<0,01) e não houve diferença entre as Fases 2 e 3. Os Gram-positivos representaram 57% dos microrganismos isolados no período pré-intervenção e 45 e 58%, respectivamente, nos períodos pós-intervenção. CONCLUSÕES: A abordagem educacional interdisciplinar e o estabelecimento de normas para inserção e intervenção no processo de manutenção de cateteres reduziram as taxas de infecção da corrente sanguínea relacionada ao cateter venoso central em uma Unidade de Terapia Intensiva Pediátrica.

Bench-to-bedside review: therapeutic management of invasive candidiasis in the intensive care unit

Candida is one of the most frequent pathogens in bloodstream infections, and is associated with significant morbidity and mortality. The epidemiology of species responsible for invasive candidiasis, both at local and worldwide levels, has been changing - shifting from Candida albicans to non-albicans species, which can be resistant to fluconazole (Candida krusei and Candida glabrata) or difficult to eradicate because of biofilm production (Candida parapsilosis). Numerous intensive care unit patients have multiple risk factors for developing this infection, which include prolonged hospitalisation, use of broad-spectrum antibiotics, presence of intravascular catheters, parenteral nutrition, high Acute Physiology and Chronic Health Evaluation score, and so forth. Moreover, delaying the specific therapy was shown to further increase morbidity and mortality. To minimise the impact of this infection, several management strategies have been developed - prophylaxis, empirical therapy, pre-emptive therapy and culture-based treatment. Compared with prophylaxis, empirical and pre-emptive approaches allow one to reduce the exposure to antifungals by targeting only the patients at high risk of candidemia, without delaying therapy until the moment blood Candida is identified in blood cultures. The agents recommended for initial treatment of candidemia in critically ill patients include echinocandins and lipid formulation of amphotericin B.

Antibiotic prophylaxis for dental procedures to prevent indwelling venous catheter-related infections

BACKGROUND

chronic indwelling central venous catheters are used commonly for a variety of indications. A predominant limitation of their use is catheter-related infections. Some clinicians believe that bacteremia from an invasive dental procedure could cause catheter-related infections and that antibiotic prophylaxis may prevent this complication. The topic is controversial, in large part because of the lack of clinical trial data supporting this notion.

METHODS

we performed a systematic review to determine the level of evidence to support this practice. We retrieved studies, guidelines, recommendations, case reports, and editorials on prescribing prophylactic antibiotic therapy for indwelling central venous catheters before oral/dental procedures, using a search of PubMed, National Guideline Clearinghouse, and textbooks.

RESULTS

there were no clinical trials and no documented cases of a catheter-related infection associated with an invasive dental procedure. Despite the lack of evidence, there are numerous recommendations and guidelines available in the literature that support the administration of "dental" prophylaxis.

CONCLUSION

there is no evidence to support the administration of prophylactic antibiotics to prevent catheter-related infections associated with an invasive oral procedure in patients with chronic indwelling central venous catheters.

In vitro evaluation of antibiotic lock technique for the treatment of Candida albicans, C. glabrata, and C. tropicalis biofilms

Candidaemia associated with intravascular catheter-associated infections is of great concern due to the resulting high morbidity and mortality. The antibiotic lock technique (ALT) was previously introduced to treat catheter-associated bacterial infections without removal of catheter. So far, the efficacy of ALT against Candida infections has not been rigorously evaluated. We investigated in vitro activity of ALT against Candida biofilms formed by C. albicans, C. glabrata, and C. tropicalis using five antifungal agents (caspofungin, amphotericin B, itraconazole, fluconazole, and voriconazole). The effectiveness of antifungal treatment was assayed by monitoring viable cell counts after exposure to 1 mg/mL solutions of each antibiotic. Fluconazole, itraconazole, and voriconazole eliminated detectable viability in the biofilms of all Candida species within 7, 10, and 14 days, respectively, while caspofungin and amphotericin B did not completely kill fungi in C. albicans and C. glabrata biofilms within 14 days. For C. tropicalis biofilm, caspofungin lock achieved eradication more rapidly than amphotericin B and three azoles. Our study suggests that azoles may be useful ALT agents in the treatment of catheter-related candidemia.

Preventing catheter-related bloodstream infections: an executive summary of the APIC elimination guide

This article is an executive summary of the APIC Elimination Guide for catheter-related bloodstream infections. Infection preventionists are encouraged to obtain the original, full-length APIC Elimination Guide for more thorough coverage of catheter-related bloodstream infections prevention.

Outcomes of therapy: vancomycin-resistant enterococcal bacteremia in hematology and bone marrow transplant patients

PURPOSE

The purpose of this study was to evaluate the risk factors associated with the treatment failure and 30-day mortality in hematology and bone marrow transplant patients treated with daptomycin or linezolid for vancomycin-resistant enterococci (VRE) bacteremia. The safety and tolerability of therapy was also assessed.

METHODS

This single-center, retrospective study included adult patients admitted to the hematology or bone marrow transplant service with documented vancomycin-resistant Enterococcus faecium or Enterococcus faecalis bacteremia and received at least 48 h of either linezolid or daptomycin as primary treatment. Clinical and microbiologic outcomes were assessed at day 7, 14, and 30 of hospital stay.

RESULTS

A total of 72 patients were included in the analysis. Forty-three patients received daptomycin as primary treatment and 29 received linezolid as primary treatment. Overall success rate at day 7 was 81.9%, day 14 success rate was 79.2%, and day 30 success rate was 76.4% for all patients. Forty-one patients (57.0%) had high-grade bacteremia defined as greater than one positive blood culture for VRE. The mortality rate was significantly higher if high-grade bacteremia was present (34.1% vs. 7.0%; p = 0.009).

CONCLUSIONS

This study suggests that linezolid and daptomycin are both reasonable options for treating VRE bacteremia in hematology and bone marrow transplant patients; however, patients with high-grade VRE bacteremia may be at increased risk for treatment failure.

Current strategies for the prevention and management of central line-associated bloodstream infections

Central venous catheters are an invaluable tool for diagnostic and therapeutic purposes in today’s medicine, but their use can be complicated by bloodstream infections (BSIs). While evidence-based preventive measures are disseminated by infection control associations, the optimal management of established central line-associated BSIs has been summarized in infectious diseases guidelines. We prepared an overview of the state-of-the-art of prevention and management of central line-associated BSIs and included topics such as the role of antibiotic-coated catheters, the role of catheter removal in the management, and a review of currently used antibiotic compounds and the duration of treatment.

Determinants of nosocomial infection in 6 neonatal intensive care units: an Italian multicenter prospective cohort study

BACKGROUND

Nosocomial infections are still a major cause of morbidity and mortality among neonates admitted to neonatal intensive care units (NICUs).

OBJECTIVE

To describe the epidemiology of nosocomial infections in NICUs and to assess the risk of nosocomial infection related to the therapeutic procedures performed and to the clinical characteristics of the neonates at birth and at admission to the NICU, taking into account the time between the exposure and the onset of infection.

DESIGN

A multicenter, prospective cohort study.

PATIENTS AND SETTING

A total of 1,692 neonates admitted to 6 NICUs in Italy were observed and monitored for the development of nosocomial infection during their hospital stay.

METHODS

Data were collected on the clinical characteristics of the neonates admitted to the NICUs, their therapeutic interventions and treatments, their infections, and their mortality rate. The cumulative probability of having at least 1 infection and the cumulative probability of having at least 1 infection or dying were estimated. The hazard ratio (HR) for the first infection and the HR for the first infection or death were also estimated.

RESULTS

A total of 255 episodes of nosocomial infection were diagnosed in 217 neonates, yielding an incidence density of 6.9 episodes per 1,000 patient-days. The risk factors related to nosocomial infection in very-low-birth-weight neonates were receipt of continuous positive airway pressure (HR, 3.8 [95% confidence interval {CI}, 1.7-8.1]), a Clinical Risk Index for Babies score of 4 or greater (HR, 2.2 [95% CI, 1.4-3.4]), and a gestational age of less than 28 weeks (HR, 2.1 [95% CI, 1.2-3.8]). Among heavier neonates, the risk factors for nosocomial infection were receipt of parenteral nutrition (HR, 8.1 [95% CI, 3.2-20.5]) and presence of malformations (HR, 2.3 [95% CI, 1.5-3.5]).

CONCLUSIONS

Patterns of risk factors for nosocomial infection differ between very-low-birth-weight neonates and heavier neonates. Therapeutic procedures appear to be strong determinants of nosocomial infection in both groups of neonates, after controlling for clinical characteristics.

Contemporary management of cardiovascular implantable electronic device infections

Cardiovascular implantable electronic device (CIED) implantation rate has substantially risen in the foregoing decades. Unfortunately, this upsurge in CIED implantation rate has been accompanied by a disproportionate rise in the rate of CIED infections. Device infection is a major complication of CIED implantation, necessitating removal of an infected device followed by systemic antimicrobial therapy and reimplantation of a new system. In this article, we review the current epidemiology, risk factors, diagnostic strategy and contemporary management of CIED infection. In addition, we address the vexing question of how to best manage patients with Staphylococcus aureus bacteremia, in the setting of an implanted device, but no overt clinical signs of CIED infection. Lastly, we discuss the preventive strategies to minimize risk of CIED infection.

Current management of bloodstream infections

Bloodstream infection (BSI) is a frequent complication of invasive infections. The presence of bacteremia has therapeutic and prognostic implications. Here we review recent changes in the epidemiology, diagnosis and treatment of BSI (excluding candidemia). The evidence of the impact of healthcare-association in many community-onset episodes and the increase in drug-resistant pathogens causing BSI in the community and hospitals is reviewed. The emergence of molecular methods as an alternative tool for the diagnosis of BSI and novel aspects of clinical management, particularly of some multidrug-resistant organisms. Several quality indicators related to the diagnosis and management of bacteremia in hospitals are proposed.

Epidemiology of bacteraemia in Hamad general hospital, Qatar: a one year hospital-based study

We conducted a one-year observational study from July 2007 to June 2008 to describe the epidemiology of bacteraemia at Hamad general hospital. During this period, a total of 452 episodes of bacteraemia occurred, which corresponds to a rate of 19/1000 hospital admissions. Most patients 58.8% (266/452) had community acquired bacteraemia, and primary bacteraemia accounted for 62.2% (281/452) of the cases. The most common source of bacteraemia was intravenous catheterization in 19.2% (87/452) but no source was identified in 42.9% (194/452) of the episodes. Gram-negative organisms were isolated in 63.1% (285/452) episodes with Escherichia coli being the most frequent 21.5% (97/452). Multidrug resistance was observed in 33.3% (7/21) of all Pseudomonas aeruginosa isolates, 50% (6/12) of Acinetobacter isolates and 28.6% (6/21) of Enterobacter isolates, whereas all ESBL producing Klebsiella spp. and E. coli were multiresistant. The percentages of oxacillin resistant coagulase negative Staphylococci isolates and methicillin-resistant Staphylococcus aureus isolates were 81.8% (27/33) and 13.2% (7/53) respectively. In hospital mortality was 22.5% (102/452), and inadequate treatment and septic shock were found to be independent predictors of mortality. Therefore, bloodstream infection surveillance is crucial to produce meaningful guidelines for prevention (e.g., catheter-related) and empirical treatment of bacteraemia in Qatar.

Candida tropicalis fungaemia: incidence, risk factors and mortality in a general hospital

The risk factors and clinical features of patients with Candida tropicalis fungaemia have not been fully defined. We performed a case-control study comparing 59 cases of C. tropicalis fungaemia with 177 episodes of fungaemia caused by other species of Candida in our hospital over a 24-year period (January 1985 to December 2008). Patients with C. tropicalis fungaemia were more likely to be older (median age, 67 vs. 56 years; p 0.01), to have cancer (45.5% vs. 31.6%, p 0.04), and to have the abdomen as the portal of entry (32.2% vs. 11.9%, p 0.001), and had a higher in-hospital mortality rate (61% vs. 44%, p 0.03). Multivariate analysis showed that the independent risk factors for C. tropicalis fungaemia were cancer (OR 4.5; 95% CI 1.05-3.83; p 0.03) and the abdomen as the portal of entry (OR 13.6; 95% CI 1.9-8.2; p <0.001). When survivors were compared with non-survivors, the risk factors associated with a poor outcome were neutropenia (19.4% vs. 0; p 0.03), corticosteroid treatment (36% vs. 13%; p 0.07), and septic shock (50% vs. 17.4%; p 0.01). The independent risk factors for mortality in the multivariate analysis were corticosteroid treatment (OR 8.2; 95% CI 0.9-27.7; p 0.04) and septic shock (OR 14.6; 95% CI 2.4-90.2; p 0.004), whereas urinary tract infection (OR 0.07; 95% CI 0.01-0.8; p 0.03) and catheter removal (OR 0.06; 95% CI 0.01-0.4; p 0.002) were protective factors. C. tropicalis is the fourth most common cause of fungaemia in our hospital. It is associated with underlying malignancy, the abdomen as the portal of entry, and poor outcome.

Catheter-related bacteremia caused by methicillin-resistant coagulase negative staphylococci with elevated minimal inhibitory concentration for vancomycin

Treatment of bacteremia caused by methicillin-resistant coagulase-negative staphylococci with vancomycin minimum inhibitory concentration ≥2 mg/L frequently requires central venous catheter removal in children with cancer. There are few data supporting efficacy and safety of antibiotic catheter lock or use of daptomycin or linezolid for this indication in children.

The first case of catheter-related bloodstream infection caused by Nocardia farcinica

Nocardia farcinica is an emerging pathogen in immunocompromised hosts. Even though several species of Nocardia have been reported as causative pathogens of catheter-related blood stream infections (CRBSI), CRBSI caused by N. farcinica has not been reported. A 70-yr-old man with a tunneled central venous catheter (CVC) for home parenteral nutrition was admitted with fever for two days. Norcardia species was isolated from the blood through CVC and peripheral bloods and identified to N. farcinica by 16S rRNA and rpoB gene sequence analyses. This report emphasizes the rapid and correct identification of causative agents in infectious diseases in the selection of antimicrobial agents and the consideration of catheter removal.

How much money can be saved by applying intravenous antibiotics once instead of several times a day?

BACKGROUND

The preparation, administration and monitoring of intravenous (IV) applications are time consuming and require human resources. We estimated the potential time and cost savings by replacing antibiotics given 3-4 times daily with antibiotics with similar spectrum and efficacy given once daily.

METHODS

The savings of indirect costs were estimated based on the antibiotic consumption data of a two-year period (i.e. 2007 and 2008), a nurse's mean workload per application and the average nurse's salary in Switzerland.

RESULTS

The consumption of IV antibiotics in 2007 and 2008 at the University Hospital of Basel was 29.0 and 32.2 defined daily doses (DDD) per 100 patient days, respectively. Nurses spent an estimated 13,786 h on the application of the estimated 82,715 does of IV antibiotics. A total of 56,404 applications or nursing staff time costs of 338,436 Swiss Francs (CHF; 236,669 <euro>), equal to 16% of the overall costs spent on purchasing antibiotics in the year 2008, may have been saved by switching multiple-dose antibiotics to a hypothetical once-daily antibiotic. Including disposable materials, 21% or 456,884 CHF (319,499 <euro>) could be saved annually (purchase costs not taken into account).

CONCLUSION

We found a potential cost saving of 21% of the purchase costs in a 750-bed institution. Hence, indirect costs should be included in the calculation of the total cost for the application of broad-spectrum IV antibiotics. Switching from a 3-4 times daily application to a once-daily antibiotic should be considered if a once-daily antibiotic is deemed equally effective and has a similar spectrum.

Microbiological pattern of arterial catheters in the intensive care unit

BACKGROUND

Intravascular catheter related infection (CRI) is one of the most serious nosocomial infections. Diagnostic criteria include a positive culture from the catheter tip along with blood, yet in many patients with signs of infection, current culture techniques fail to identify pathogens on catheter segments. We hypothesised that a molecular examination of the bacterial community on short term arterial catheters (ACs) would improve our understanding of the variety of organisms that are present in this niche environment and would help develop new methods for the diagnosis of CRI.

RESULTS

The whole bacterial community presenting on all ACs was evaluated by molecular methods, i.e., a strategy of whole community DNA extraction, PCR amplification followed by cloning and 16S rDNA sequence analysis. Ten ACs were removed from patients suspected of CRI and 430 clones from 5 "colonised" and 5 "uncolonised" (semi-quantitative method) AC libraries were selected for sequencing and subsequent analysis. A total of 79 operational taxonomic units (OTUs) were identified at the level of 97% similarity belonging to six bacterial divisions. An average of 20 OTUs were present in each AC, irrespective of colonisation status. Conventional culture failed to reveal the majority of these bacteria.

CONCLUSIONS

There was no significant difference in the bacterial diversity between the 'uncolonised' and 'colonised' ACs. This suggests that vascular devices cultured conventionally and reported as non infective may at times potentially be a significant source of sepsis in critically ill patients. Alternative methods may be required for the accurate diagnosis of CRI in critically ill patients.

Physical compatibility of 4% sodium citrate with selected antimicrobial agents

PURPOSE

The physical compatibility of 4% sodium citrate with vancomycin, gentamicin, tobramycin, daptomycin, and linezolid was evaluated.

METHODS

Admixtures were prepared by mixing 4% sodium citrate with clinically relevant concentrations of antimicrobial agents (vancomycin 5 mg/mL, vancomycin 10 mg/mL, vancomycin 20 mg/mL, daptomycin 5 mg/mL, gentamicin 2.4 mg/mL, tobramycin 2.4 mg/mL, and linezolid 1 mg/mL). Three samples of each admixture were incubated (1) at 22-23 degrees C and exposed to light, (2) in a water bath at 37 degrees C and exposed to light, (3) at 22-23 degrees C and protected from light, and (4) in a water bath at 37 degrees C and protected from light. Visual compatibility, spectrophotometric absorbance, and pH were evaluated immediately after mixing (baseline) and at 8, 24, and 48 hours. Physical compatibility was defined as the absence of visible precipitation, a pH value at 48 hours that did not vary by more than 10% from baseline, and an absorbance value of <0.015.

RESULTS

There was no visual evidence of precipitation and no clinically important changes in pH observed during the 48-hour study period in any admixture. However, turbidity, based on absorbance, was noted with vancomycin 20 mg/mL at each time point.

CONCLUSION

No evidence of incompatibility was observed when vancomycin 5 mg/ mL, vancomycin 10 mg/mL, daptomycin 5 mg/mL, gentamicin 2.4 mg/mL, tobramycin 2.4 mg/mL, or linezolid 1 mg/mL was mixed with 4% sodium citrate as might occur in an antimicrobial lock. Vancomycin 20 mg/mL mixed with 4% sodium citrate displayed spectrophotometric evidence of incompatibility.

A dynamic in vitro model for evaluating antimicrobial activity against bacterial biofilms using a new device and clinical-used catheters

The activity of daptomycin compared to vancomycin against Staphylococcus epidermidis-biofilms on intravascular catheters has been evaluated using the new Sevilla device that enables to use medical grade-catheters, in an in vitro model that simulates the in vivo conditions. S. epidermidis-biofilms were obtained on polyurethane catheter segments using the Sevilla device linked to a continuous culture system for 24 h. To assess the antimicrobial activity, at this time the continuous culture system was changed to therapeutic antimicrobial concentration solutions for 48 h. At each 24 h interval time, catheter segments were taken out, washed and sonicated. Viable adherent bacteria were determined by agar plating. Data of surviving bacteria numbers attached to the catheter surface obtained with the Sevilla device showed a very good reproducibility. Daptomycin showed a good activity against S. epidermidis-biofilm on polyurethane catheter surface. After 48 h exposure to daptomycin, surviving adherent bacteria were reduced by 4 log compared to the control with no antimicrobial. Using the same model, vancomycin reduced bacterial survival by only 1.3 log. The Sevilla device enables antimicrobial agent activity against bacterial biofilms grown on the external surface of catheters used in clinical practice to be evaluated. The model used replicates as closely as possible the biofilm formed in a highly standardized way. Using this model, daptomycin demonstrates potent in vitro activity against S. epidermidis-biofilm on a polyurethane catheter; this activity was greater than that showed by vancomycin.

Common complications in the surgical intensive care unit

Surgical and trauma intensive care units provide the facilities, resources, and personnel needed to care for patients who have been severely injured, present with acute surgical emergencies, require prolonged and complex elective surgical procedures, or have severe underlying medical conditions. Correcting the immediately evident physiologic derangement is only the first step in the care of these patients, because in many cases their prognosis and ultimate outcome will depend on whether additional insults accrued during their intensive care unit and hospital stay will prevent them from a full recovery. The nature, number, and complexity of the interventions used to provide advanced support requires a unique attention to the concept of patient safety, particularly when the population involved is that most vulnerable to injury and with the least amount of physiologic reserve to recover from it. The medical community, the public, and even regulatory agencies have focused on specific preventable complications that are common in surgical and injured patients, such as medical errors, healthcare-associated infections, and venous thromboembolism. Enough scientific knowledge has been obtained through well-conducted clinical trials to generate detailed evidence-based guidelines for the prevention and management of some of these pathologies, but still there are outstanding questions in terms of the applicability of the recommendations to the critically ill. In addition to clinical and technical expertise, performance improvement and quality monitoring activities provide direction for system solutions required to properly address many complications that are not provider specific.

Supportive care in children

PURPOSE OF REVIEW

To provide an update on the rational approach of febrile neutropenia in children with cancer and discuss future research aspects in the field.

RECENT FINDINGS

Clinical and laboratory variables and new biomarkers associated with an increased risk for a severe outcome including invasive bacterial infection (IBI), sepsis, and mortality have been identified for children with cancer and febrile neutropenia. These variables and biomarkers are currently being used for an early risk assessment in order to identify children at low or high risk for IBI or at high risk for sepsis and death. Early identification of children with a differential risk has allowed the implementation of selective treatment regimens. More recently, host genetic differences have been associated with a differential risk for IBI. The individual gene profile based on selected polymorphisms could further fine-tune the early risk assessment allowing tailor-made management strategies.

SUMMARY

In the last decades, efforts have focused on the stratification of the heterogeneous group of children with cancer and febrile neutropenia according to their risk for developing an IBI. This effort has allowed a less aggressive treatment strategy for children at low risk, including early hospital discharge and use of intravenous and oral antimicrobials at home. More recently, advances have been made in the early identification of children in the other spectrum of infection, those at high risk for sepsis and mortality, with the aim of rapid implementation of aggressive therapy.