Relationship between Clinical Outcomes and Vascular Access Type among Hemodialysis Patients withStaphylococcus aureusBacteremia

Guidelines on vascular access for hemodialysis from the Brazilian Society of Angiology and Vascular Surgery

Chronic kidney disease is a worldwide public health problem, and end-stage renal disease requires dialysis. Most patients requiring renal replacement therapy have to undergo hemodialysis. Therefore, vascular access is extremely important for the dialysis population, directly affecting the quality of life and the morbidity and mortality of this patient population. Since making, managing and salvaging of vascular accesses falls within the purview of the vascular surgeon, developing guideline to help specialists better manage vascular accesses for hemodialysis if of great importance. Thus, the objective of this guideline is to present a set of recommendations to guide decisions involved in the referral, evaluation, choice, surveillance and management of complications of vascular accesses for hemodialysis.

Staphylococcus aureus Bacteremia Among Patients Receiving Maintenance Hemodialysis: Trends in Clinical Characteristics and Outcomes

RATIONALE & OBJECTIVE

Staphylococcus aureus (Saureus) bacteremia (SAB) is associated with morbidity and mortality in patients receiving maintenance hemodialysis (HD). We evaluated changes in clinical and bacterial characteristics, and their associations with clinical outcomes with SAB in this population over a 21-year period.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

453 hospitalized, non-neutropenic adults receiving maintenance HD who developed monomicrobial SAB between 1995 and 2015.

EXPOSURE

Clinical characteristics and bacterial genotype.

OUTCOME

All-cause and SAB-attributable mortality, persistent bacteremia, and metastatic complications.

ANALYTICAL APPROACH

Proportions of participants experiencing each outcome were calculated overall and by calendar year. Secular trends were estimated using binomial risk regression, a generalized linear model with the log link function for a binomial outcome. Associations with outcomes were estimated using logistic regression.

RESULTS

Over the 21-year study period, patients receiving maintenance HD experienced significant increases in age- and diabetes-adjusted SAB-attributable mortality (0.45% [95% CI, 0.36%-0.46%] per year), persistent bacteremia (0.86% [95% CI, 0.14%-1.55%] per year), metastatic complications (0.84% [95% CI, 0.11%-1.56%] per year), and infection with the virulent Saureus clone USA300 (1.47% [95% CI, 0.33%-2.52%] per year). Over time, the suspected source of SAB was less likely to be a central venous catheter (-1.32% [95% CI, -2.05 to-0.56%] per year) or arteriovenous graft (-1.08% [95% CI, -1.54 to-0.56] per year), and more likely to be a nonvascular access source (1.89% [95% CI, 1.29%-2.43%] per year). Patients with a nonvascular access suspected source of infection were more likely to die as a result of their S aureus infection (OR, 3.20 [95% CI, 1.36-7.55]). The increase in USA300 infections may have contributed to the observed increase in persistent bacteremia (OR, 2.96 [95% CI, 1.12-7.83]) but did not explain the observed increases in SAB-attributable mortality (OR, 0.83 [95% CI, 0.19-3.61]) or metastatic complications (OR, 1.34 [95% CI, 0.53-3.41]).

LIMITATIONS

Single-center, inpatient cohort.

CONCLUSIONS

The clinical and molecular epidemiology of SAB in patients receiving maintenance HD has changed over time, with an increase in SAB-attributable mortality and morbidity despite a decline in catheter-related infections.

Central Venous Catheters for Hemodialysis-the Myth and the Evidence

Hemodialysis-central venous catheter (HD-CVC) insertion is a most often performed procedure, with approximately 80% of patients with end-stage kidney disease in the United States initiating kidney replacement therapy through a HD-CVC. Certain adverse events arising from HD-CVC placement, including catheter-related bloodstream infections (CR-BSIs), thrombosis, and central vein stenosis, can complicate the clinical course of patients and lead to considerable financial impact on the health care system. Medical professionals with different training backgrounds are responsible for performing this procedure, and therefore, comprehensive operator guidelines are crucial to improve the success rate of HD-CVC insertion and prevent complications. In this review article, we not only discuss the basic principles behind the use of HD-CVCs but also address frequently asked questions and myths regarding catheter asepsis, length selection, tip positioning, and flow rate assessment.

Arteriovenous Grafts' Types of Indications and Their Infection Rate

BACKGROUND

Arteriovenous graft infection is a well-known and frequent complication. The objective of this study was to compare infection rates of primary and secondary indicated arteriovenous grafts (AVGs).

SUBJECTS AND METHODS

Retrospectively, we evaluated the indications for AVGs created at our institution which became infected. One hundred forty AVGs were evaluated. Of these AVGs, 33 (23.6%) were primary and 107 (76.4%) secondary indicated.

RESULTS

Infection of a primary AVG was detected in 5 patients (15.2 %). Infection of a secondary AVG was detected in 30 patients (28.0%). Primary and secondary patency were significantly lower in patients with infected AVG (P = 0.006; P = 0.0001). The effect of diabetes mellitus and age on development of infection was not confirmed.

CONCLUSIONS

Indications for AVG creation clearly influence the future risk of infection. If the indication to use the AVG is to correct a complicated arteriovenous fistula, the risk of infection is 2 times higher.

Higher Risk for All-cause Mortality of Staphylococcus aureus Bacteremia in Patients with Non-Dialysis Dependent Chronic Kidney Disease

Background

Staphylococcus aureus bacteremia (SAB) is a common and serious infection with a high mortality. Patients with chronic kidney disease (CKD) are vulnerable to SAB, but there have been few studies performed on the clinical characteristics and outcomes of SAB in CKD patients stratified by dialysis. We aimed to estimate the all-cause mortality and identify its predictors in patients with CKD.

Materials and Methods

We conducted a retrospective study on the patients with SAB hospitalized in a tertiary care center in Korea between March 2014 and December 2018. Kaplan-Meier analysis was performed to compare all-cause mortality following SAB among patients with non-dialysis dependent CKD (ND-CKD), those receiving dialysis, and those without CKD (non-CKD). The predictors of mortality among CKD patients were analyzed by Cox proportional hazards regression.

Results

As a total, 278 SAB of 43 ND-CKD (31 males), 58 dialysis (39 males), and 177 non-CKD (112 males) patients were included. The 30-day mortality was 39.5% in ND-CKD, 27.6% in dialysis, and 7.9% in non-CKD patients. The hazard ratio of all-cause mortality following SAB in ND-CKD was 2.335 (95% confidence interval, 1.203 – 4.531; P = 0.003), compared to non-CKD patients. For methicillin-resistant S. aureus bacteremia (MRSAB), the hazard ratio of all-cause mortality in ND-CKD was 2.628 (95% CI, 1.074 – 6.435; P = 0.011), compared to dialysis patients. Appropriate antibiotics <48 h was independently related to improved survival following SAB among ND-CKD (adjusted HR, 0.304; 95% CI, 0,108 – 0.857; P = 0.024) and dialysis (adjusted HR, 0.323; 95% CI, 0,116 – 0.897; P = 0.030) patients.

Conclusion

ND-CKD patients demonstrated poor outcome following SAB and administration of appropriate antibiotics within 48 h could reduce the risk for mortality.

Survival and Cost-Effectiveness of Trabectedin Compared to Ifosfamide Monotherapy in Advanced Soft Tissue Sarcoma Patients

Trabectedin and ifosfamide are among the few cytostatic agents active in advanced soft tissue sarcomas (STSs). Trabectedin is most potent against so-called L-sarcomas (leiomyosarcoma and liposarcoma). The survival gain and cost-effectiveness of these agents in a second-line setting were analysed in the setting of advanced STS after failure of anthracyclines. A prospective observational trial had previously been performed to assess the use of trabectedin in a Dutch real-world setting. Data on ifosfamide monotherapy were acquired from previous studies, and an indirect comparison of survival was made. A state-transition economic model was constructed, in which patients could be in mutually exclusive states of being preprogression, postprogression, or deceased. The costs and quality-adjusted life years (QALYs) for both treatments were assessed from a Dutch health-care perspective. Separate analyses for the group of L-sarcomas and non-L-sarcomas were performed. Trabectedin treatment resulted in a median progression-free survival of 5.2 months for L-sarcoma patients, 2.0 months for non-L-sarcoma patients, and a median overall survival of 11.8 and 6.0 months, respectively. For L-sarcoma patients, trabectedin offered an increase of 0.368 life years and 0.251 QALYs compared to ifosfamide and €20,082 in additional costs, for an incremental cost-effectiveness ratio (ICER) of €80,000 per QALY gained. In the non-L-sarcoma patients, trabectedin resulted in 0.413 less life years and 0.266 less QALYs, at the increased cost of €4,698. The difference in survival between drugs and the acquisition costs of trabectedin were the main influences in these models. Trabectedin was shown to have antitumour efficacy in advanced L-sarcoma. From a health economics perspective, the costs per QALY gained compared to ifosfamide monotherapy that may be acceptable, considering what is currently regarded as acceptable in the Netherlands.

Increased risk of Staphylococcus aureus bacteremia in hemodialysis-A nationwide study

INTRODUCTION

Staphylococcus aureus bacteremia (SAB) is a high-risk infection and feared complication related to hemodialysis. This study aimed to investigate incidence and risk factors for SAB depending on hemodialysis access type.

METHODS

The Danish National Registry on Regular Dialysis and Transplantation was used to identify patients from January 1, 1996 to December 31, 2011 with end-stage kidney disease. Patients were followed until death, the first episode of SAB, or end of study (December 31, 2011). Independent risk factors were assessed by multivariable Poisson regression with time-updated exposure variables.

FINDINGS

Total of 9997 patients were included. The initial modality of renal replacement therapy was hemodialysis in 6826 patients and peritoneal dialysis in 2882 patients; 289 patients had preemptive kidney transplantation. SAB occurred in 1278 patients (12.8%). The incidence rate of SAB declined after 90 days and leveled off after 270 days in hemodialysis, peritoneal dialysis, and kidney transplanted. As compared to peritoneal dialysis, the adjusted rate ratio (RR) for SAB was 7.42 (95% CI 5.63-9.79) in uncuffed central venous catheter (CVC), 5.68 (95% CI 4.39-7.36) in cuffed CVC, 4.43 (95% CI 2.10-9.53) in arteriovenous graft, and 3.40 (95% CI 2.79-4.15) in arteriovenous fistula. SAB risk did not differ between uncuffed and cuffed CVC. The risk of SAB was increased during the first three months of renal replacement therapy especially for CVC (RR 11.37 [95% CI7.09-18.22]) compared with peritoneal dialysis. Diabetes mellitus (RR 1.35 [95% CI 1.20-1.51]) and male sex (RR 1.15 [95% CI 1.03-1.29]) were also associated with SAB.

DISCUSSION

Patients on hemodialysis had a high incidence rate of SAB, particularly those undergoing hemodialysis via CVC. SAB risk was comparable for cuffed and uncuffed CVC. Diabetes mellitus, male sex, and the first three months in renal replacement therapy were independently associated with SAB.

Ferritin Light Chain Confers Protection Against Sepsis-Induced Inflammation and Organ Injury

Despite the prevalence and recognition of its detrimental impact, clinical complications of sepsis remain a major challenge. Here, we investigated the effects of myeloid ferritin heavy chain (FtH) in regulating the pathogenic sequelae of sepsis. We demonstrate that deletion of myeloid FtH leads to protection against lipopolysaccharide-induced endotoxemia and cecal ligation and puncture (CLP)-induced model of sepsis as evidenced by reduced cytokine levels, multi-organ dysfunction and mortality. We identified that such protection is predominantly mediated by the compensatory increase in circulating ferritin (ferritin light chain; FtL) in the absence of myeloid FtH. Our in vitro and in vivo studies indicate that prior exposure to ferritin light chain restrains an otherwise dysregulated response to infection. These findings are mediated by an inhibitory action of FtL on NF-κB activation, a key signaling pathway that is implicated in the pathogenesis of sepsis. We further identified that LPS mediated activation of MAPK pathways, specifically, JNK, and ERK were also reduced with FtL pre-treatment. Taken together, our findings elucidate a crucial immunomodulatory function for circulating ferritin that challenges the traditional view of this protein as a mere marker of body iron stores. Accordingly, these findings will stimulate investigations to the adaptive nature of this protein in diverse clinical settings.

Spanish Clinical Guidelines on Vascular Access for Haemodialysis

Vascular access for haemodialysis is key in renal patients both due to its associated morbidity and mortality and due to its impact on quality of life. The process, from the creation and maintenance of vascular access to the treatment of its complications, represents a challenge when it comes to decision-making, due to the complexity of the existing disease and the diversity of the specialities involved. With a view to finding a common approach, the Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology [S.E.N.], vascular surgery [SEACV], vascular and interventional radiology [SERAM-SERVEI], infectious diseases [SEIMC] and nephrology nursing [SEDEN]), along with the methodological support of the Cochrane Center, has updated the Guidelines on Vascular Access for Haemodialysis, published in 2005. These guidelines maintain a similar structure, in that they review the evidence without compromising the educational aspects. However, on one hand, they provide an update to methodology development following the guidelines of the GRADE system in order to translate this systematic review of evidence into recommendations that facilitate decision-making in routine clinical practice, and, on the other hand, the guidelines establish quality indicators which make it possible to monitor the quality of healthcare.

Surgical Excision of Infected Arteriovenous Grafts: Technique and Review

Infected prosthetic arteriovenous grafts for hemodialysis present a profound risk to patient well being. Here we present five recent cases and describe our technique for total graft excision. We also review the literature and discuss the much debated role of partial, subtotal, and total graft excision.

A prospective comparison of the performance and survival of two different tunnelled haemodialysis catheters: SplitCath® versus DuraMax®

BACKGROUND

Despite their well-recognised shortcomings, haemodialysis catheters (HDCs) remain an important form of haemodialysis access for many patients. There are several HDCs commercially available, each differing considerably in design, which is known to significantly influence performance and survival. We sought to determine which of two tunnelled HDCs, DuraMax® (Angiodynamics, NY, USA) or SplitCath® (MedComp, PA, USA) delivers the best performance, safety and reliability for dialysis patients.

METHODS

Eighty-six patients were prospectively randomised to receive either DuraMax® (DM) or SplitCath® (SC). Outcomes included: (i) mean flow rates (mL/min) averaged over the first 10 weeks of dialysis, and urea reduction ratio (URR); and (ii) long-term catheter survival with appraisal of any events leading to catheter dysfunction and early removal.

RESULTS

Median flow rates (interquartile range) in the DM and SC groups were 321 (309-343) and 309 (294-322) mL/min, respectively (p = 0.002). URR values for the DM and SC groups were 71 (65-76) and 74 (70-78), respectively, (p = 0.094). There was no significant difference in long-term survival or frequency of incidents that required early HDC removal (9/43 in the DM group, 5/43 patients SC). A slightly higher incidence of HDC dislodgement was noted in the DM group, although this study was not statistically powered to determine its significance.

CONCLUSIONS

We conclude that DM yields slightly higher flow rates in the first 10 weeks of dialysis, and a similar low incidence of complications and long-term survival for both DM and SC HDCs.

Catheter-related bloodstream infection in end-stage kidney disease: a Canadian narrative review

Purpose of the review

Patients with end-stage renal disease (ESRD) are at a high risk of bacterial infection. We reviewed publications on risk factors, prevention, and treatment paradigms, as well as outcomes associated with bacterial infection in end-stage kidney disease. We focused in particular on studies conducted in Canada where rates of haemodialysis catheter use are high.

Sources of information

We included original research articles in English text identified from MEDLINE using search terms ‘chronic kidney failure’, ‘renal dialysis’, or ‘chronic renal insufficiency’, and ‘bacterial infection’. We focused on articles with Canadian study populations and included comparisons to international standards and outcomes where possible.

Findings

Bacterial infections in this setting are most commonly due to Gram-positive skin flora, particularly Staphylococcus, with methicillin-resistant Staphylococcus aureus (MRSA) carrying a poorer prognosis. Interventions that may decrease mortality from sepsis include a collaborative care model that includes a nephrology team, an infectious disease specialist, and use of standardized care bundles that adhere to proven quality-of-care indicators. Decreased infectious mortality may be achieved by ensuring appropriate antibiotic selection and dosing as well as avoiding catheter salvage attempts. Reduction in bloodstream infection (BSI) incidence has been observed with the use of tPA catheter-locking solutions and the use of mupirocin or polysporin as a topical agent at the catheter exit site, as well as implementing standarized hygiene protocols during catheter use.

Limitations

There has been a paucity of randomized controlled trials of prevention and treatment strategies for catheter-related BSIs in haemodialysis. Some past trials have been limited by lack of blinding and short duration of follow-up. Microbiological epidemiology, although well characterized, may vary by region and treatment centre.

Implications

With the high prevalence of catheter use in Canadian haemodialysis units, further studies on long-term treatment and preventative strategies for BSI are warranted.

Infection Rates Following Buttonhole Cannulation in Hemodialysis Patients

Arteriovenous fistula (AVF) is the preferred access for hemodialysis (HD). Buttonhole (BH) needling has increased following the introduction of "blunt" fistula needles. Although some reported advantages for BH needling, others have reported increased infection risk. As such we reviewed our center practice, and the effect of both nasal screening and eradication and re-education and training programs. We audited the outcomes of 881 HD patients dialyzed between November 2009 and May 2012, divided into three groups: 175 dialyzing exclusively by central venous catheter (CVC), 478 exclusively by area needling AVF (AVF) and 219 by BH. There were 31 Staphylococcus aureus bacteremias (SABs); 14 (45.2%) dialyzing with CVCs, 12 (38.7%) BH and five (16.1%) AVF. The 30 day mortality rate for SAB was 7.5% with a complication rate of 22.6%. The hazard ratio for first SAB was significantly greater for both CVC and BH access compared to AVF (5.3 (95% CI -1.9-18.6), P < 0.001 and 3.6 (1.3-96), P = 0.011, respectively). During the study SAB rates per 1000 CVC days were 0.21, compared to 0.15 for BH. After major re-education and asepsis technique campaigns the SAB rate for BH fell to 0.06, but quickly returned to 0.17. Extending BH needling to all our dialysis centers, SAB infection rates increased to those not dissimilar to CVC access. Despite re-education programs coupled with a strict asepsis policy and active SA eradication, followed by audit cycles, the increased infection risk with BH remained, such that we have limited BH to self-care patients.

Daptomycin antibiotic lock therapy for hemodialysis patients with Gram-positive bloodstream infections following use of tunneled, cuffed hemodialysis catheters: retrospective single center analysis

Catheter-related blood stream infection (CRBSI) is a major complication in hemodialysis patients. We assessed the efficacy of systemic daptomycin (DPT) plus DPT antibiotic lock therapy (DPT-ALT) for catheter salvage in patients with Gram-positive CRBSIs. This is a retrospective study of hemodialysis patients with tunneled and cuffed hemodialysis catheters. All patients were from a single institution in Taipei and received systemic DPT plus DPT-ALT for the treatment of Gram-positive CRBSI. Successful resolution of CRBSI was implemented. Resolution of fever within 48 hours, negative result of repeated blood cultures after resolution of fever, no clinical evidence of CRBSI relapse and no need for catheter removal were measured. Fifteen hemodialysis patients received DPT-ALT for CRBSI, nine with coagulase-negative Staphylococcus (CONS), two with methicillin-resistant Staphylococcus aureus (MRSA), three with methicillin-sensitive Staphylococcus aureus (MSSA) and one with polymicrobial infections. Systemic DPT plus DPT-ALT cured 11 patients (73.3%). Treatment failed in all three MRSA cases (two with MRSA and one with MRSA + Enterococcus faecalis). Retrospective design and small sample size were the limitations of this study. Systemic DPT plus DPT-ALT appears to be a promising treatment for CRBSI from CONS and MSSA, but not for MRSA CRBSI. Systemic DPT plus DPT-ALT should be considered for patients with CRBSIs caused by certain species.

Staphylococcus aureus infections: epidemiology, pathophysiology, clinical manifestations, and management

Staphylococcus aureus is a major human pathogen that causes a wide range of clinical infections. It is a leading cause of bacteremia and infective endocarditis as well as osteoarticular, skin and soft tissue, pleuropulmonary, and device-related infections. This review comprehensively covers the epidemiology, pathophysiology, clinical manifestations, and management of each of these clinical entities. The past 2 decades have witnessed two clear shifts in the epidemiology of S. aureus infections: first, a growing number of health care-associated infections, particularly seen in infective endocarditis and prosthetic device infections, and second, an epidemic of community-associated skin and soft tissue infections driven by strains with certain virulence factors and resistance to β-lactam antibiotics. In reviewing the literature to support management strategies for these clinical manifestations, we also highlight the paucity of high-quality evidence for many key clinical questions.

Trends in US Vascular Access Use, Patient Preferences, and Related Practices: An Update From the US DOPPS Practice Monitor With International Comparisons

BACKGROUND

Since the bundled end-stage renal disease prospective payment system began in 2011 in the United States, some hemodialysis practices have changed substantially, raising the question of whether vascular access practice also has changed. We describe monthly US vascular access use from August 2010 to August 2013 with international comparisons, and other aspects of US vascular access practice.

STUDY DESIGN

Prospective observational cohort study of vascular access.

SETTING & PARTICIPANTS

Maintenance hemodialysis patients in the Dialysis Outcomes and Practice Patterns Study (DOPPS) Practice Monitor (DPM) in the United States (N=3,442; US patients) and 19 other nations (N=8,478).

PREDICTORS

Country, patient demographics, time period.

OUTCOMES

Vascular access use, pre-end-stage renal disease access timing of first nephrologist care and arteriovenous access placement, patient self-reported vascular access preferences (United States only), treatment practices as stated by medical directors.

RESULTS

In the United States from August 2010 to August 2013, arteriovenous fistula (AVF) use increased from 63% to 68%, while catheter use declined from 19% to 15%. Although AVF use did not differ greatly across age groups, arteriovenous graft use was 2-fold higher among black (26%) versus nonblack US patients (13%) in 2013. Across 20 countries in 2013, AVF use ranged from 49% to 92%, whereas catheter use ranged from 1% to 45%. Patient-reported vascular access preferences differed by sex and race, with 16% to 20% of patients feeling uninformed regarding benefits/risks of different vascular access types. Among new (incident) US hemodialysis patients, AVF use remains low, with ∼70% initiating hemodialysis therapy with a catheter (60% starting with catheter when having ≥4 months of predialysis nephrology care). In the United States, longer typical times to first AVF cannulation were reported.

LIMITATIONS

Noncompletion of surveys may affect the generalizability of findings to the wider hemodialysis population.

CONCLUSIONS

AVF use has increased, with catheter use decreasing among prevalent US hemodialysis patients since the introduction of the prospective payment system. However, AVF use at dialysis therapy initiation remains low, suggesting that reforms affecting predialysis care may be necessary to incentivize improvements in fistula rates at dialysis therapy initiation as achieved for prevalent hemodialysis patients.

Prevention of Central Line–Associated Bloodstream Infections in Hemodialysis Patients

An increasing proportion of central line-associated bloodstream infections (CLABSIs) are seen in outpatient settings. Many of such infections are due to hemodialysis catheters (HD-CLABSIs). Such infections are associated with substantial morbidity, mortality, and excess healthcare costs. Patients who receive dialysis through a catheter are 2–3 times more likely to be hospitalized for infection and to die of septic complications than dialysis patients with grafts or fistulas. Prevention measures include minimizing the use of hemodialysis catheters, use of CLABSI prevention bundles for line insertion and maintenance, and application of antimicrobial ointment to the catheter exit site. Instillation into dialysis catheters of antimicrobial solutions that remain in the catheter lumen between dialyses (antimicrobial lock solutions) has been studied, but it is not yet standard practice in some dialysis units. At least 34 studies have evaluated the impact of antimicrobial lock solutions on HD-CLABSI rates. Thirty-two (94%) of the 34 studies demonstrated reductions in HD-CLABSI rates among patients treated with antimicrobial lock solutions. Recent multicenter randomized controlled trials demonstrated that the use of such solutions resulted in significantly lower HD-CLABSI rates, even though such rates were low in control groups. The available evidence supports more routine use of antimicrobial lock solutions as an HD-CLABSI prevention measure in hemodialysis units.

Iliopsoas abscess as a complication of tunneled jugular vein catheterization in a hemodialysis patient

Iliopsoas abscess is a rare complication in hemodialysis patients that is mainly due to adjacent catheterization, local acupuncture, discitis, and bacteremia. Herein, we report a 47-year-old woman undergoing regular hemodialysis via a catheter in the internal jugular vein who presented with low back pain and dyspnea. A heart murmur suggested the presence of catheter-related endocarditis, and this was confirmed by an echocardiogram and a blood culture of methicillin-resistant Staphylococcus aureus. A computed tomography indicated a pulmonary embolism and an incidental finding of iliopsoas abscess. Following surgical intervention and intravenous daptomycin, the patient experienced full recovery and a return to usual activities. This case indicates that an iliopsoas abscess can be related to a jugular vein catheter, which is apparently facilitated by infective endocarditis. The possibility of iliopsoas abscess should be considered when a hemodialysis patient presents with severe low back pain, even when there is no history of adjacent mechanical intervention.

Endocarditis Is a Common Stroke Mechanism in Hemodialysis Patients

Background and Purpose—

Hemodialysis patients are at high risk for ischemic stroke, and previous studies have noted a high rate of cardioembolism in this population. The aim of this study was to determine ischemic stroke causes among hemodialysis patients and elucidate specific cardioembolic stroke mechanisms.

Methods—

This study is a retrospective cross-sectional study of hemodialysis patients admitted with acute stroke to the University of Pennsylvania Health System between 2003 and 2010. Strokes were classified using modified Trial of Org 10 172 in Acute Stroke Treatment (TOAST) criteria as large vessel, cardioembolism, small vessel, atypical, multiple causes, or cryptogenic. Cardioembolic strokes were further characterized for specific mechanism.

Results—

We identified 52 patients hospitalized with acute stroke while receiving hemodialysis. Mean age was 64±13 years, 56% were female, and 67% were black. Stroke subtypes included 3 (6%) large vessel, 20 (38%) cardioembolism, 6 (11%) small vessel, 3 (6%) other, 4 (8%) with multiple causes, and 16 (31%) were unknown. Among patients who had an echocardiogram performed, 5 of 52 (10%; 95% confidence interval, 1%–18%) had a patent foramen ovale. Cardioembolic stroke mechanisms included 6 with infective endocarditis (accounting for 12% of all strokes).

Conclusions—

Cardioembolism and cryptogenic stroke are the predominant stroke mechanisms among hemodialysis patients. Infective endocarditis was identified frequently relative to other stroke cohorts, and a raised index of suspicion is warranted in the hemodialysis population.

Vascular access in therapeutic apheresis: update 2013

This review addresses the types of vascular access available for patients who need therapeutic apheresis (TA). As in hemodialysis, vascular access for TA is chosen based on type of procedure prescribed, the patient's vascular anatomy, the acuity, frequency and duration of treatment, and the underlying disease state. The types of access available include peripheral vein cannulation, central venous catheters: including nontunneled and tunneled catheters, arterio-venous grafts and arterio-venous fistulas. Peripheral veins and central venous catheters are most frequently utilized for the acute administration of TA, and may be used over a period of weeks to months. Arterio-venous grafts and fistulas are not commonly used in TA procedures, but are an option in patients with an anticipated long course of TA, usually for a period of several months or years. The types and frequency of complications associated with various types of vascular access, including: access dysfunction and infections are reviewed, and strategies for their prevention and management are offered.

Invasive methicillin-resistant Staphylococcus aureus infections among patients on chronic dialysis in the United States, 2005-2011

BACKGROUND

Approximately 15 700 invasive methicillin-resistant Staphylococcus aureus (MRSA) infections occurred in US dialysis patients in 2010. Frequent hospital visits and prolonged bloodstream access, especially via central venous catheters (CVCs), are risk factors among hemodialysis patients. We describe the epidemiology of and recent trends in invasive MRSA infections among dialysis patients.

METHODS

We analyzed population-based data from 9 US metropolitan areas from 2005 to 2011. Cases were defined as MRSA isolated from a normally sterile body site in a surveillance area resident who received dialysis, and were classified as hospital-onset (HO; culture collected >3 days after hospital admission) or healthcare-associated community-onset (HACO; all others). Incidence was calculated using denominators from the US Renal Data System. Temporal trends in incidence and national estimates were calculated controlling for age, sex, and race.

RESULTS

From 2005 to 2011, 7489 cases were identified; 85.7% were HACO infections, and 93.2% were bloodstream infections. Incidence of invasive MRSA infections decreased from 6.5 to 4.2 per 100 dialysis patients (annual decrease, 7.3%) with annual decreases of 6.7% for HACO and 10.5% for HO cases. Among cases identified during 2009-2011, 70% of patients were hospitalized in the year prior to infection. Among hemodialysis cases, 60.4% of patients were dialyzed through a CVC. The 2011 national estimated number of MRSA infections was 15 169.

CONCLUSIONS

There has been a substantial decrease in invasive MRSA infection incidence among dialysis patients. Most cases had previous hospitalizations, suggesting that efforts to control MRSA in hospitals might have contributed to the declines. Infection prevention measures should include improved vascular access and CVC care.

Catheter-related infections in chronic hemodialysis: a clinical and economic perspective

PURPOSE

Central venous catheters emerged as a major risk factor for infectious complications in hemodialysis (HD) patients. We aimed to assess the incidence of bacteremia in catheter-dependent HD patients and to characterize its clinical and economic impact.

METHODS

We retrospectively collected clinical data and healthcare costs from 15 months for 75 admitted catheter-dependent HD patients, to document the type of bacteremia (complicated or not), pathogen and inflammation.

RESULTS

Bacteremia (97 % with Staphylococcus aureus, 33 % methicillin-resistant) was present in 51 % patients, with an overall infections incidence of 5.79 per 1,000 catheter-days. Metastatic complications occurred in 21 % of bacteremic patients and were associated with higher mortality (38 vs. 4 %; p = 0.001). Although, in patients starting dialysis on catheter (41 %) as compared to those using catheter as bridge angioaccess, inflammation (higher C-reactive protein; p = 0.006) and anemia (lower Hb; p = 0.008) were more pronounced, bacteremia occurred in a lower proportion (32 vs. 64 %, p = 0.007). The total medical costs were 47 % higher in patients with complicated bacteremia than in those without bacteremia (p = 0.008) and 45 % higher in patients starting HD on catheter than in those using catheter as bridge angioaccess (p = 0.002).

CONCLUSIONS

Despite the limitations resulting from retrospective cross-sectional single-center design, our study suggests that patients already on HD who required catheters as bridge angioaccess were more prone to bacteremia. This highlights the importance of close angioaccess monitoring to avoid unnecessary catheter usage. A similar increase in costs when initiating dialysis on catheter as in case of complicated bacteremia strongly supports the initial placement of a native arteriovenous fistula.

The potential economic value of a Staphylococcus aureus vaccine among hemodialysis patients

Staphylococcus aureus infections are a substantial problem for hemodialysis patients. Several vaccine candidates are currently under development, with hemodialysis patients being one possible target population. To determine the potential economic value of an S. aureus vaccine among hemodialysis patients, we developed a Markov decision analytic computer simulation model. When S. aureus colonization prevalence was 1%, the incremental cost-effectiveness ratio (ICER) of vaccination was ≤$25,217/quality-adjusted life year (QALY). Vaccination became more cost-effective as colonization prevalence, vaccine efficacy, or vaccine protection duration increased or vaccine cost decreased. Even at 10% colonization prevalence, a 25% efficacious vaccine costing $100 prevented 29 infections, 21 infection-related hospitalizations, and 9 inpatient deaths per 1000 vaccinated HD patients. Our results suggest that an S. aureus vaccine would be cost-effective (i.e., ICERs ≤ $50,000/QALY) among hemodialysis patients over a wide range of S. aureus prevalence, vaccine costs and efficacies, and vaccine protection durations and delineate potential target parameters for such a vaccine.

Infectious complications in dialysis--epidemiology and outcomes

This Review focuses on the changing epidemiology of infections among patients with end-stage renal disease who are undergoing dialysis. In particular, bloodstream infections related to vascular access in patients undergoing hemodialysis, and peritonitis in patients undergoing peritoneal dialysis, are highlighted. Gram-positive (staphylococcal and enterococcal) bloodstream infections and Gram-negative peritonitis (especially extended-spectrum β-lactamase-producing organisms) contribute substantially to excess health-care use owing to infection caused by dialysis access. Although the management of peritoneal-dialysis-related peritonitis has been hampered by a dearth of randomized, controlled studies, epidemiological data have provided useful information. To overcome the problem of differing methods used to monitor infections within various dialysis centers, uniform reporting systems for vascular-access-related infection and peritoneal-dialysis-related peritonitis, as recommended by the Centers for Disease Control and Prevention and the International Society for Peritoneal Dialysis, respectively, are discussed. Infections unrelated to the port of entry for dialysis are also examined, namely hepatitis and respiratory infection. To address the disease burden, we examine the infection-related mortality as well as the implications for subsequent cardiovascular mortality.

DNA microarray genotyping and virulence and antimicrobial resistance gene profiling of methicillin-resistant Staphylococcus aureus bloodstream isolates from renal patients

Thirty-six methicillin-resistant Staphylococcus aureus (MRSA) bloodstream isolates from renal patients were genetically characterized by DNA microarray analysis and spa typing. The isolates were highly clonal, belonging mainly to ST22-MRSA-IV. The immune evasion and enterotoxin gene clusters were found in 29/36 (80%) and 33/36 (92%) isolates, respectively.

Catheter-related bacteremia in hemodialysis patients: the role of the central venous catheter in prevention and therapy

Infections are a leading cause of morbidity and mortality in patients with end-stage renal disease. Infections in hemodialysis patients are strongly associated with the use of an indwelling central venous catheter. S. aureus, coagulase-negative staphylococci and Gram-negative rods account for the majority of these infections. The outcome of catheter-related bacteremia depends on appropriate antibiotic therapy and management of the hemodialysis catheter. Most studies note that there is no difference in outcome if the catheter is changed over a guidewire in addition to antibiotic therapy or if the catheter is completely removed and reinserted at a later date. However, bacteremia with certain organisms, particularly S. aureus, is associated with complications. Thus, the data suggests that the catheter needs to be promptly removed in patients developing S. aureus bacteremia.Bacterial biofilm likely has a critical role in the pathogenesis of these infections. Numerous in vitro and in vivo studies have demonstrated both a reduction in infection rate with the use of antibiotic catheter locks as well as a reduction in the production of or eradication of bacterial biofilm. Future studies ought to target, firstly, a reduction in the reliance on central venous catheters; and secondly, the formulation of practical strategies to reduce patient risk for developing catheter-related bacteremia.

Facility hemodialysis vascular access use and mortality in countries participating in DOPPS: an instrumental variable analysis

BACKGROUND

Previously, the Dialysis Outcomes and Practice Patterns Study (DOPPS) has shown large international variations in vascular access practice. Greater mortality risks have been seen for hemodialysis (HD) patients dialyzing with a catheter or graft versus a native arteriovenous fistula (AVF). To further understand the relationship between vascular access practice and outcomes, we have applied practice-based analyses (using an instrumental variable approach) to decrease the treatment-by-indication bias of prior patient-level analyses.

STUDY DESIGN

A prospective observational study of HD practices.

SETTING & PARTICIPANTS

Data collected from 1996 to 2004 from 28,196 HD patients from more than 300 dialysis units participating in the DOPPS in 12 countries.

PREDICTOR OR FACTOR

Patient-level or case-mix-adjusted facility-level vascular access use. OUTCOMES/MEASUREMENTS: Mortality and hospitalization risks.

RESULTS

After adjusting for demographics, comorbid conditions, and laboratory values, greater mortality risk was seen for patients using a catheter (relative risk, 1.32; 95% confidence interval, 1.22 to 1.42; P < 0.001) or graft (relative risk, 1.15; 95% confidence interval, 1.06 to 1.25; P < 0.001) versus an AVF. Every 20% greater case-mix-adjusted catheter use within a facility was associated with 20% greater mortality risk (versus facility AVF use, P < 0.001); and every 20% greater facility graft use was associated with 9% greater mortality risk (P < 0.001). Greater facility catheter and graft use were both associated with greater all-cause and infection-related hospitalization. Catheter and graft use were greater in the United States than in Japan and many European countries. More than half the 36% to 43% greater case-mix-adjusted mortality risk for HD patients in the United States versus the 5 European countries from the DOPPS I and II was attributable to differences in vascular access practice, even after adjusting for other HD practices. Vascular access practice differences accounted for nearly 30% of the greater US mortality compared with Japan.

LIMITATIONS

Possible existence of unmeasured facility- and patient-level confounders that could impact the relationship of vascular access use with outcomes.

CONCLUSIONS

Facility-based analyses diminish treatment-by-indication bias and suggest that less catheter and graft use improves patient survival.

Outcomes of Staphylococcus aureus infection in hemodialysis-dependent patients

BACKGROUND AND OBJECTIVES

Staphylococcus aureus is a leading cause of infection in patients with ESRD. Clinical and economic outcomes associated with S. aureus bacteremia and other S. aureus infections in patients with ESRD were examined.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Laboratory, clinical, and hospital billing data from a randomized trial of 3359 hemodialysis-dependent patients hospitalized with S. aureus infection in the United States whose vascular access type was fistula or graft and who were hospitalized with S. aureus infection to evaluate inpatient costs, hospital days, and mortality over 12 wk were used. Generalized linear regression was used to identify independent predictors of 12-wk costs, inpatient days, and mortality.

RESULTS

Of the 279 patients (8.3%) who developed S. aureus infection during approximately 1 yr of follow-up, 25.4% were treated as outpatients. Among patients for whom billing data were available, 89 patients hospitalized with S. aureus bacteremia incurred mean 12-wk inpatient costs of $19,454 and 11.9 inpatient days. Among the 70 patients hospitalized with non-bloodstream S. aureus infections, mean inpatient costs were $19,222 and the mean number of inpatient days was 11.3. Twelve-week mortality was 20.2 and 15.7% for patients with S. aureus bloodstream and non-bloodstream infections, respectively. Older age was independently associated with higher risk of death among patients with S. aureus bacteremia and with higher inpatient costs and more hospital days among patients with non-bloodstream infections.

CONCLUSIONS

Hemodialysis-dependent patients with fistula or graft access incur high costs and long inpatient stays when hospitalized for S. aureus infection.