Septicemia in dialysis patients: incidence, risk factors, and prognosis

Hemodialysis access usage patterns in the incident dialysis year and associated catheter-related complications

BACKGROUND

Hemodialysis (HD) access is considered a critical and actionable determinant of morbidity, with a growing literature suggesting that initial HD access type is an important marker of long-term outcomes. Accordingly, we examined HD access during the incident dialysis period, focusing on infection risk and successful fistula creation during the first dialysis year.

STUDY DESIGN

Longitudinal cohort.

SETTING & PARTICIPANTS

All US adults admitted to Fresenius Medical Care North America facilities within 15 days of first maintenance dialysis session between January 1 and December 31, 2007.

PREDICTOR

Vascular access type at HD therapy initiation.

OUTCOMES

Vascular access type at 90 days and at the end of the first year on HD therapy, bloodstream infection within the first year by access type, and catheter complication rate.

RESULTS

Of 25,003 incident dialysis patients studied, 19,622 (78.5%) initiated dialysis with a catheter; 4,151 (16.6%), with a fistula; and 1,230 (4.9%), with a graft. At 90 days, 14,105 (69.7%) had a catheter, 4,432 (21.9%) had a fistula, and 1,705 (8.4%) had a graft. Functioning fistulas and grafts at dialysis therapy initiation had first-year failure rates of 10% and 15%, respectively. Grafts were seldom replaced by fistulas (3%), whereas 7,064 (47.6%) of all patients who initiated with a catheter alone still had only a catheter at 1 year. Overall, 3,327 (13.3%) patients had at least one positive blood culture during follow-up, with the risk being similar between the fistula and graft groups, but approximately 3-fold higher in patients with a catheter (P<0.001 for either comparison). Nearly 1 in 3 catheters (32.5%) will require tissue plasminogen activator use by a median of 41 days, with 59% requiring more than one tissue plasminogen activator administration.

LIMITATIONS

Potential underestimation of bacteremia because follow-up blood culture results did not include samples sent to local laboratories.

CONCLUSIONS

In a large and representative population of incident US dialysis patients, catheter use remains very high during the first year of HD care and is associated with high mechanical complication and bloodstream infection rates.

Vascular access type, health-related quality of life, and depression in hemodialysis patients: a preliminary report

PURPOSE

Arteriovenous fistulas (AVF) are the vascular access of choice for hemodialysis (HD) compared with arteriovenous grafts (AVG) and central venous catheters (CVC). In spite of increasing recognition of importance of a patient's perception of health-related quality of life (HRQOL) and depression, few studies have assessed the association of vascular access type with HRQOL and depression. The purpose of our study was to examine HRQOL and depression among patients with different vascular access.

METHODS

Severity of symptoms of depression and HRQOL were assessed by Beck Depression Inventory (BDI) and Short Form-36 (SF-36), respectively. Vascular access was reported as one of three options; AVF, AVG, and CVC.

RESULTS

In total, 136 patients were included; 104 had AVF, 15 had AVG, and 17 had CVC. BDI and HRQOL parameters differed among patients with different vascular access types. In post hoc analysis, BDI and HRQOL subscales were not different between patients with AVF and AVG. Patients with CVC had lower physical functioning (P:.001), role-physical limitation (P:.015), general health perception (P:.017), vitality (P:.010), social functioning (P:.004), role-emotional (P:.008), mental health (P:.001), physical component summary score (P:.017), and mental component summary score (P:.006) when compared to patients with AVF. Patients with CVC had lower physical functioning (P:.044), role-emotional (P:.044) and mental health scores (P:.04) when compared to patients with AVG.

CONCLUSIONS

Having a CVC may negatively influence HRQOL in HD patients. Vascular access type does not seem to be related to depressed mood in HD.

Association of dialysis modality with risk for infection-related hospitalization: a propensity score-matched cohort analysis

BACKGROUND AND OBJECTIVES

Peritonitis is a well known complication of peritoneal dialysis (PD), whereas in hemodialysis (HD), bacteremia can be life threatening. Whether patients undergoing PD have higher risk than HD patients for infection-related hospitalizations (IRH) remains unknown.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A propensity score-matched retrospective cohort of patients undergoing long-term dialysis between January 2001 and December 2007 was assembled. Propensity scores were calculated using multivariable (demographic characteristics, smoking, body mass index, comorbid conditions, and laboratory data) logistic regression to estimate probability of receiving PD versus HD. A comparison of IRH risk by dialysis modality was estimated using a counting-process survival model.

RESULTS

A total of 910 pairs of patients were matched by propensity scores. During a median follow-up of 2.1 years (interquartile range, 1.1-3.5 years), 341 patients were hospitalized once for an infection, 123 twice, and 106 at least three times. PD was associated with an increased risk for IRH compared with HD (propensity-matched hazard ratio [HR], 1.52). PD was associated with a reduced risk for septicemia (HR, 0.31) and pneumonia (HR, 0.58) but also an increased risk for dialysis-related infectious hospitalizations (HR, 3.44), defined as all cases of peritonitis and vascular access-related bacteremia, but not all septicemia cases.

CONCLUSIONS

PD patients are at higher risk for IRH than are HD patients. This risk is mostly explained by dialysis-related infections. However, further studies are needed to evaluate whether the severity of those hospitalizations is similar and whether this increased risk for IRH is associated with worse outcomes.

Antibiotic lock solutions allow less systemic antibiotic exposure and less catheter malfunction without adversely affecting antimicrobial resistance patterns

There are current concerns that antibiotic lock solutions (ABL) can induce antimicrobial resistance in long-term hemodialysis patients. Retrospective chart review of 157 children on hemodialysis between January 1997 and June 2006 was performed. In ERA I, only systemic antibiotics were used. In ERA II, ABL were added to systemic antibiotics when needed. In ERA III, ABL were used for treatment of all cases of catheter-related bacteremia (CRB) and for CRB prophylaxis in high-risk patients. The study includes 111,325 catheter days. The CRB incidence was 3.9 CRB/1000 catheter days. There was significant decrease for the total systemic antibiotic exposure (P = 0.0484) and the percentage of catheters lost to malfunction (P = 0.001) in ERA III. Protocol ABL exposure was associated with a trend to increased tobramycin-gentamicin resistance for gram-positive CRBs (P = 0.2586) but with improved tobramycin-gentamicin resistance for gram-negative (P = 0.0949) and polymicrobial CRBs (P = 0.1776) and improved vancomycin resistance for gram-positive CRBs (P = 0.0985). This retrospective analysis does not support the premise that ABL use will promote antimicrobial resistance in the hemodialysis population. The decreased exposure to systemic antibiotics by vigorous ABL use may even improve the antimicrobial resistance patterns in this population in the long term.

High mortality rate of infectious diseases in dialysis patients: a comparison with the general population in Japan

Infectious disease is the second leading cause of death among dialysis patients, and it is generally assumed that the mortality rate of infectious disease is considerably higher in dialysis patients than in the general population. There are no comprehensive studies on this issue and on the contribution of each category of infectious disease to excess mortality in dialysis patients in Japan. We used mortality data reported to the Japanese Society for Dialysis Therapy and national Vital Statistics data for 2008 and 2009. We calculated standardized mortality ratios and compared the mortality rates for each category of infectious disease. During the 2-year study period, 274,683 and 10,435 deaths from infectious diseases were recorded in 126 million people and 273,237 dialysis patients, respectively. The standardized mortality ratio for all infectious diseases was 7.5 (95% confidence interval, 7.3-7.6) in dialysis patients with respect to the general population in Japan. The categories of infectious disease with a significantly higher standardized mortality ratio among the dialysis patients were sepsis, peritonitis, influenza, tuberculosis, and pneumonia and in that order. In particular, the mortality rate of sepsis contributed to 69.5% of the difference in infectious disease mortality between dialysis patients and the general population. This study underlines markedly increased mortality from infectious diseases, particularly from sepsis, in dialysis patients compared with the general population.

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.

Iron Inhibits Respiratory Burst of Peritoneal Phagocytes In Vitro

Objective. This study examines the effects of iron ions Fe³⁺ on the respiratory burst of phagocytes isolated from peritoneal effluents of continuous ambulatory peritoneal dialysis (CAPD) patients, as an in vitro model of iron overload in end-stage renal disease (ESRD). Material and Methods. Respiratory burst of peritoneal phagocytes was measured by chemiluminescence method. Results. At the highest used concentration of iron ions Fe³⁺ (100 μM), free radicals production by peritoneal phagocytes was reduced by 90% compared to control. Conclusions. Iron overload may increase the risk of infectious complications in ESRD patients.

Linezolid versus vancomycin antibiotic lock solution for the prevention of nontunneled catheter-related blood stream infections in hemodialysis patients: a prospective randomized study

The use of antibiotic lock solutions (ALSs) for the prevention of catheter-related blood stream infections (CRBSIs) is a promising option. The efficacy and safety of linezolid as ALS were evaluated in a randomized double-blind prospective study where 131 patients who required nontunneled catheter (NTC) for hemodialysis (HD) were randomized to receive an ALS with either (A) unfractionated heparin (2000 U/ml) alone as a catheter lock control, (B) vancomycin (5 mg/ml) + heparin (2000 U/ml), or (C) linezolid (2 mg/ml) + heparin (2000 U/ml). The primary endpoint of the study was CRBSI. A total of 152 NTCs were inserted in 131 patients. The linezolid-locked group did not present any infective episode (CRBSI rate = 0/1000 catheter days) compared with 2 episodes in the vancomycin-locked group (CRBSI rate = 1.21/1000 catheter days, p = 0.1021) and 11 episodes in the heparin-locked group (CRBSI rate = 6.7/1000 catheter days, p = 0.0001). Median number of catheter days was greater in group C (median = 38) compared with group B (median = 36, p = 0.0415) and with group A (median = 34, p = 0.0036). No side effects and no resistant organisms were recorded with the use of linezolid ALS. Linezolid appears to be a safe and effective ALS, preventing CRBSI and prolonging the survival of the catheter in HD patients.

Palliative care in the treatment of end-stage renal failure

Palliative care begins with establishing goals of care based on estimated prognosis in end-stage renal disease (ESRD). Patients with ESRD are increasingly characterized by older age and multiple comorbid illnesses, and have a mortality rate 8 times higher than the general Medicare population. Dialysis patients are appropriate for palliative care because of their high mortality rate and high symptom burden. More patients and families are choosing not to start or withdraw dialysis for multiple reasons, particularly in patients older than 60 years. Advance directives and resuscitation directives are important in ensuring compassionate and goal-directed palliative care of ESRD patients. Drug toxicities are avoidable by using appropriate drugs at the correct doses and dosing intervals.

Veterans more likely to start hemodialysis with an arteriovenous fistula

Hemodialysis via arteriovenous fistulas (AVFs) is associated with reduced morbidity and mortality when compared to alternative vascular accesses, yet few patients in the United States start dialysis with AVFs. Recent studies have demonstrated higher quality of care for many conditions in Veterans Affairs' Medical Centers (VAMC); however, differences in quality of vascular access care are unknown. We used patient-level data (6/05-5/06) from Medicare claims (n = 25,912) to compare the proportions of AVF among incident patients at VAMC-affiliated (n = 20) and unaffiliated dialysis (n = 1631) facilities. Multivariate logistic regression was used to determine whether associations of access type with facility type were independent. Compared to non-VAMC patients, a larger proportion of VAMC patients started dialysis with AVFs (20.9% versus 11.6% in non-VAMC patients; OR 1.99, [95% CI 1.55-2.56]). Although attenuated, this finding persisted in models adjusted for demographics (OR 1.65 [95% CI 1.28-2.13]) and demographics with comorbidities (OR 1.70 [95% CI 1.31-2.20]). However, after accounting for pre end-stage renal disease (ESRD) care, similar proportions of VAMC and non-VAMC patients started hemodialysis with an AVF (OR 1.28 [95% CI 0.98-1.66]). In conclusion, patients receiving care at VAMC-associated facilities were more likely to start hemodialysis with AVFs, perhaps because of better pre-ESRD care. Nonetheless, AVF rates remain suboptimal, indicating a need for ongoing vascular access evaluation and improvement.

Chronic kidney disease and risk of death from infection

BACKGROUND

Infection, bacteremia and sepsis are major sources of morbidity and mortality in patients with end-stage renal disease. This study sought to determine the association between predialysis chronic kidney disease (CKD) and infection-related mortality.

METHODS

We analyzed participants in the Third National Health and Nutrition Examination Survey (NHANES III). The study included adults ≥45- years-old without end-stage renal disease. Estimated glomerular filtration rate (eGFR) was categorized as ≥60, 45-59.9 and <45 ml/min per 1.73 m(2), and urinary albumin-to-creatinine ratio (ACR) as <30, 30-299.9 and ≥300 mg/g. The study identified infection-related mortality, including septicemia, respiratory, abdominal and gastrointestinal, cardiac, kidney and genitourinary, neurologic, and other infections over a median of 13 years using the National Death Index.

RESULTS

Of 7,400 participants included in the study, 206 died from infections. Compared to individuals with eGFR ≥60 ml/min per 1.73 m(2), infection-related mortality was higher for those with lower eGFR [adjusted HR = 1.36 (95% CI: 0.81, 2.30) and 2.36 (1.04, 5.38) for eGFR of 45-59.9 and <45 ml/min per 1.73 m(2), respectively; p trend = 0.06]. Compared to individuals with ACR <30 mg/g, infection-related mortality was higher for ACR levels of 30-299 and ≥300 mg/g [adjusted HR = 1.68 (95% CI: 0.97, 2.92) and 2.84 (0.92, 8.74), p trend = 0.02].

CONCLUSIONS

Reduced eGFR and albuminuria are associated with increased risk for infection-related mortality. Efforts are needed to reduce its incidence and mitigate the effects of infections among individuals with CKD.

The spectrum of infections in catheter-dependent hemodialysis patients

BACKGROUND AND OBJECTIVES

Catheter-dependent hemodialysis patients may develop access-related and nonaccess-related infections that may be managed in the outpatient arena or in the hospital. The goal of this study was to quantify infections in such patients, to characterize their clinical presentations, and to evaluate factors determining need for hospitalization.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We collected prospective data on the clinical management of catheter-dependent hemodialysis patients with suspected infection at a large dialysis center. We documented the presenting symptoms, type of infection, pathogen, and whether hospitalization occurred.

RESULTS

An infection was suspected in 305 separate cases and confirmed in 88%. The 268 diagnosed infections included catheter-related bacteremia (69%), another access-related infection (19%), and nonaccess-related infection (12%). The overall frequency of infection was 4.62 per 1000 catheter-days. Hospitalization occurred in 37% of all infections, but it varied greatly (72% for nonaccess-related infection, 34% for catheter-related bacteremia, and 4% for exit-site infection). Among patients with catheter-related bacteremia, the likelihood of hospitalization varied by pathogen, being 53% for Staphylococcus aureus, 30% for Enterococcus, 23% for Staphylococcus epidermidis, and 17% for gram-negative rods (P < 0.001). The likelihood of hospitalization was not associated with age, gender, or diabetes. Fever was a presenting symptom in only 47% of cases of catheter-related bacteremia.

CONCLUSIONS

Catheter-dependent patients have a high burden of infection. It is important to evaluate patients with suspected infection for various access-related and nonaccess-related infections. A low threshold is indicated for suspecting catheter-related bacteremia because the patients frequently present without fever.

Case study: first implantation of a frozen, devitalized tissue-engineered vascular graft for urgent hemodialysis access

Previously we reported on the mid- to long-term follow-up in the first clinical trial to use a completely autologous tissue-engineered graft in the high pressure circulation. In these early studies, living grafts were built from autologous fibroblasts and endothelial cells obtained from small skin and vein biopsies. The graft was assembled using a technique called tissue-engineering by self-assembly (TESA), where robust conduits were grown without support from exogenous biomaterials or synthetic scaffolding. One limitation with this earlier work was the long lead times required to build the completely autologous vascular graft. Here we report the first implant of a frozen, devitalized, completely autologous Lifeline™ vascular graft. In a departure from previous studies, the entire fibroblast layer, which provides the mechanical backbone of the graft, was air-dried then stored at -80°C until shortly before implant. Five days prior to implant, the devitalized conduit was rehydrated, and its lumen was seeded with living autologous endothelial cells to provide an antithrombogenic lining. The graft was implanted as an arteriovenous shunt between the brachial artery and the axillary vein in a patient who was dependent upon a semipermanent dialysis catheter placed in the femoral vein. Eight weeks postoperatively, the graft functions without complication. This strategy of preemptive skin and vein biopsy and cold-preserving autologous tissue allows the immediate availability of an autologous arteriovenous fistula, and is an important step forward in our strategy to provide allogeneic tissue-engineered grafts available "off-the-shelf".

In Peritoneal Dialysis, Is There Sufficient Evidence to Make "PD First" Therapy?

Since its introduction more than 3 decades ago, the use of peritoneal dialysis (PD) has increased greatly due to its simplicity, convenience, and low cost. Advances in technique, antibiotic prophylaxis, and the introduction of newer solutions have improved survival, quality of life, and reduced rate of complications with PD. In Hong Kong, approximately 80% end-stage renal disease (ESRD) patients perform PD; in others, that is, Canada, Australia, and New Zealand, 20%-30% patients use PD. However, in the United States, the annual rate of prevalent patients receiving PD has reduced to 8% from its peak of 15% in mid-1980s. PD as the initial modality is being offered to far less patients than hemodialysis (HD), resulting in the current annual incidence rate of less than 10% in USA. There are many reasons preventing the PD first initiative including the increased numbers of in-center hemodialysis units, physician comfort with the modality, perceived superiority of HD, risk of peritonitis, achieving adequate clearances, and reimbursement incentives to providers. Patient fatigue, membrane failure, and catheter problems are other reasons which discourage PD utilization. In this paper, we discuss the available evidence and provide rationale to support PD as the initial renal replacement modality for ESRD patients.

Blood Loss through AV Fistula: A Case Report and Literature Review

Little has been written about acute blood loss from hemodialysis vascular access. We describe a 57-year-old Caucasian male with an approximately 7 gm/dL drop in hemoglobin due to bleeding from a ruptured aneurysm in his right brachiocephalic arteriovenous fistula (AVF). There was no evidence of fistula infection. The patient was successfully managed by blood transfusions and insertion of a tunneled dialysis catheter for dialysis access. Later, the fistula was ligated and a new fistula was constructed in the opposite arm. Aneurysm should be considered in cases of acute vascular access bleeding in chronic dialysis patients.

Active vitamin D and acute respiratory infections in dialysis patients

BACKGROUND AND OBJECTIVES

Vitamin D has gained attention for its pleiotropic effects in areas other than bone metabolism, and the effects of vitamin D in preventing respiratory infections have been reported as one of its immunomodulating properties. This study assessed the preventive effect of vitamin D receptor activator (VDRA) on respiratory infections in dialysis patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Maintained Japanese hemodialysis patients (n = 508) were observed for 5 years, and the incidence of hospitalization during this period because of acute respiratory infection (ARI) was recorded.

RESULTS

Of the 508 patients, 212 had taken oral VDRA at the start of the study, whereas 296 patients had not received it. During the 5-year follow-up period, 57 patients were hospitalized because of ARIs. Kaplan-Meier analysis revealed that the incidence of hospitalization because of respiratory infection was significantly lower in patients who had been treated with VDRA compared with patients who had not (log rank test; P = 0.02). The multivariate Cox proportional hazards model demonstrated that the patients who had taken oral VDRA were at a significantly lower risk of hospitalization because of respiratory disease (hazard ratio 0.47, 95% confidence interval 0.25 to 0.90).

CONCLUSIONS

The findings of this study suggest that the administration of oral VDRA has a preventive effect on the incidence of ARIs in dialysis patients.

Preventing catheter-related infections in children undergoing hemodialysis

The increased use of tunneled cuffed catheters in children on chronic hemodialysis is the result of their relative ease of insertion, pain-free dialysis and immediate use. The disadvantage of their use is that they are associated with catheter-related bacteremia (CRB), which in turn is related with increased morbidity, access loss and occasionally metastatic infections and even death. A CRB might be difficult to diagnose and is often associated with a previous history of CRB, exit-site infection, low serum albumin and long duration of catheter use. There is evidence that the use of arteriovenous fistulae is associated with lower infection rates. The implementation of effective strategies for the prevention of CRBs include the adoption of policies for improving arteriovenous fistula rates, appropriate surgical catheter insertion and optimal nursing care of the exit site, and a safe connection technique. Recently, the effectiveness of antimicrobial catheter solutions for preventing CRB has been documented in a number of randomized clinical trials. In addition, the application of antibiotic ointments at the exit sites of tunneled cuffed catheters might be significant for the reduction of Staphylococcus-related CRB. The upside is that education-based programs combining specific preventive measures can significantly reduce CRBs.

A crossover intervention trial evaluating the efficacy of a chlorhexidine-impregnated sponge in reducing catheter-related bloodstream infections among patients undergoing hemodialysis

BACKGROUND

Catheter-related bloodstream infections (CRBSIs) account for the majority of hemodialysis-related infections. There are no published data on the efficacy of the chlorhexidine-impregnated foam dressing at reducing the rate of CRBSI among patients undergoing hemodialysis.

DESIGN

A prospective, nonblinded, crossover intervention trial to determine the efficacy of a chlorhexidine-impregnated foam dressing to reduce the rate of CRBSI among patients undergoing hemodialysis.

SETTING

Two outpatient dialysis centers.

PATIENTS

A total of 121 patients who underwent dialysis through tunneled central venous catheters received the intervention during the trial.

METHODS

The primary outcome of interest was the incidence of CRBSI. A nested cohort study of all patients who received the chlorhexidine-impregnated foam dressing was also conducted. Backward stepwise logistic regression analysis was used to determine independent risk factors for development of CRBSI.

RESULTS

Thirty-seven CRBSIs occurred in the intervention group, for an incidence of 6.3 CRBSIs per 1,000 dialysis sessions, and 30 CRBSIs occurred in the control group, an incidence of 5.2 CRBSIs per 1,000 dialysis sessions (risk ratio, 1.22 [95% confidence interval {CI}, 0.75-1.97]; P = .46). The chlorhexidine-impregnated foam dressing was well tolerated, with only 2 patients (<2%) experiencing dermatitis that led to its discontinuation. The only independent risk factor for development of CRBSI was dialysis treatment at one dialysis center (adjusted odds ratio, 4.4 [95% CI, 1.77-13.65]; P = .002). Age of at least 60 years (adjusted odds ratio, 0.28 [95% CI, 0.09-0.82]; P = .02) was associated with lower risk of CRBSI.

CONCLUSIONS

The use of a chlorhexidine-impregnated foam dressing did not decrease the incidence of CRBSI among patients with tunneled central venous catheters who were undergoing hemodialysis.

Haemodialysis catheters increase mortality as compared to arteriovenous accesses especially in elderly patients

BACKGROUND

Catheter use has been associated with an increased mortality risk in haemodialysis patients. However, differences in the all-cause and cause-specific mortality risk between catheter use and arteriovenous access use in young and elderly haemodialysis patients have not yet been investigated.

METHODS

In this prospective cohort study of 1109 incident haemodialysis patients from 38 centres in the Netherlands, hazard ratios (HRs) with 95% confidence intervals (95% CIs) were calculated for 2-year all-cause, infection-related and cardiovascular mortality in patients with a catheter as compared to patients with an arteriovenous access stratified for age (< 65 years and ≥ 65 years).

RESULTS

Of the 1109 patients, 919 had an arteriovenous access and 190 had a catheter. The mortality rate was 76 per 1000 person-years in young patients with an arteriovenous access, 129 per 1000 person-years in young patients with a catheter, 222 per 1000 person-years in elderly patients with an arteriovenous access and 427 per 1000 person-years in elderly patients with a catheter. The adjusted HR was 3.15 (95% CI: 2.09-4.75) for elderly patients with a catheter as compared to young patients with an arteriovenous access. The adjusted HRs in elderly patients with a catheter as compared to elderly patients with an arteriovenous access were 1.54 (95% CI: 1.13-2.12) for all-cause mortality, 1.60 (95%: CI 0.62-4.19) for infection-related mortality and 1.67 (95% CI: 1.04-2.68) for cardiovascular mortality.

CONCLUSIONS

Especially, elderly haemodialysis patients with a catheter have an increased all-cause, infection-related and cardiovascular mortality risk as compared to patients with an arteriovenous access.

Diagnosis and treatment of infective endocarditis in chronic hemodialysis patients

OBJECTIVE

To analyze the clinical features of hemodialysis patients complicated by infective endo carditis.

METHODS

The clinical features of six such patients admitted to Peking Union Medical College Hospital during the year 1990 to 2009 were analyzed. All of them were diagnosed based on Chinese Children Diagnostic Criteria for Infective Endocarditis.

RESULTS

The average age of the six patients was 52.3 +/- 19.3 years old. Four were males. Vascular accesses at the onset of infective endocarditis were as follows: permanent catheters in three, temporary catheters in two, and arteriovenous fistula in one. Three were found with mitral valve involvement, two with aortic valve involvement, and one with both. Five vegetations were found by transthoracic echocardiography, and one by transesophageal echocardiography. Four had positive blood culture results. The catheters were all removed. Four of the patients were improved by antibiotics treatment, in which two were still on hemodialysis in the following 14-24 months and the other two were lost to follow-up. One patient received surgery, but died of heart failure after further hemodialysis for three months. One was well on maintenance hemodialysis for three months after surgery.

CONCLUSIONS

Infective endocarditis should be suspected when hemodialysis patients suffer from long-term fever, for which prompt blood culture and transthoracic echocardiography confirmation could be performed. Transesophageal echocardiography could be considered even when transthoracic echocardiography produces negative findings. With catheters removed, full course of appropriate sensitive antibiotics and surgery if indicated could improve the outcome of chronic hemodialysis patients complicated by infective endocarditis.

Peritoneal dialysis first: rationale

The use of peritoneal dialysis (PD) has become wide spread since the introduction of continuous ambulatory PD more than 25 years ago. Over this time, many advances have been made and PD is an alternative to hemodialysis (HD), with excellent comparable survival, lower cost, and improved quality of life. The percentage of prevalent PD patients in the United States is approximately 7%, which is significantly lower compared with the 15% PD prevalence from the mid-1980s. Despite comparable survival of HD and PD and improved PD technique survival over the last few years, the percentage of patients performing PD in the United States has declined. The increased numbers of in-center HD units, physician comfort with the modality, perceived superiority of HD, and reimbursement incentives have all contributed to the underutilization of PD. In addition to a higher transplantation rate among patients treated with PD in the United States, an important reason for the low PD prevalence is the transfer to HD. There are various reasons for the transfer (e.g., episodes of peritonitis, membrane failure, patient fatigue, etc.). This review discusses the various factors that contribute to PD underutilization and the rationale and strategies to implement "PD first" and how to maintain it. The PD first concept implies that when feasible, PD should be offered as the first dialysis modality. This concept of PD first and HD second must not be seen as a competition between therapies, but rather that they are complementary, keeping in mind the long-term goals for the patient.

Impact of chronic kidney disease on survival after amputation in individuals with diabetes

OBJECTIVE

To identify factors that influence survival after diabetes-related amputations.

RESEARCH DESIGN AND METHODS

We abstracted medical records of 1,043 hospitalized subjects with diabetes and a lower-extremity amputation from 1 January to 31 December 1993 in six metropolitan statistical areas in south Texas. We identified mortality in the 10-year period after amputation from death certificate data. Diabetes was verified using World Health Organization criteria. Amputations were identified by ICD-9-CM codes 84.11-84.18 and categorized as foot, below-knee amputation, and above-knee amputation and verified by reviewing medical records. We evaluated three levels of renal function: chronic kidney disease (CKD), hemodialysis, and no renal disease. We defined CKD based on a glomerular filtration rate<60 ml/min and hemodialysis from Current Procedural Terminology (CPT) codes (90921, 90925, 90935, and 90937). We used χ2 for trend and Cox regression analysis to evaluate risk factors for survival after amputation.

RESULTS

Patients with CKD and dialysis had more below-knee amputations and above-knee amputations than patients with no renal disease (P<0.01). Survival was significantly higher in patients with no renal impairment (P<0.01). The Cox regression indicated a 290% increase in hazard for death for dialysis treatment (hazard ratio [HR] 3.9, 95% CI 3.07-5.0) and a 46% increase for CKD (HR 1.46, 95% CI 1.21-1.77). Subjects with an above-knee amputation had a 167% increase in hazard (HR 2.67, 95% CI 2.14-3.34), and below-knee amputation patients had a 67% increase in hazard for death.

CONCLUSIONS

Survival after amputation is lower in diabetic patients with CKD, dialysis, and high-level amputations.

Change in vascular access and hospitalization risk in long-term hemodialysis patients

BACKGROUND AND OBJECTIVES

Conversion from central venous catheters to a graft or a fistula is associated with lower mortality risk in long-term hemodialysis (HD) patients; however, a similar association with hospitalization risk remains to be elucidated.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a prospective observational study all maintenance in-center HD patients who were treated in Fresenius Medical Care, North America legacy facilities; were alive on January 1, 2007; and had baseline laboratory data from December 2006. Access conversion (particularly from a catheter to a fistula or a graft) during the 4-month period from January 1 through April 30, 2007, was linked using Cox models to hospitalization risk during the succeeding 1-year follow-up period (until April 30, 2008).

RESULTS

The cohort (N = 79,545) on January 1, 2007 had 43% fistulas, 29% catheters, and 27% grafts. By April 30, 2007, 70,852 patients were still on HD, and among 19,792 catheters initially, only 10.3% (2045 patients) converted to either a graft or a fistula. With catheters as reference, patients who converted to grafts/fistulas had similar adjusted hazard ratios (0.69) as patients on fistulas (0.71), while patients with fistulas/grafts who converted to catheters did worse (1.22), all P < 0.0001.

CONCLUSIONS

Catheters remain associated with the greatest hospitalization risk. Conversion from a catheter to either graft or fistula had significantly lower hospitalization risk relative to keeping the catheter. Prospective studies are needed to determine whether programs that reduce catheters will decrease hospitalization risk in HD patients.

Choice of vascular access among incident hemodialysis patients: a decision and cost-utility analysis

BACKGROUND AND OBJECTIVES

Arteriovenous fistulas (AVFs) are widely accepted as the preferred hemodialysis vascular access type. However, supporting data have failed to consider morbidity and mortality incurred during failed creation attempts and may therefore overstate potential advantages. This study compares survival, quality-adjusted survival, and costs among incident hemodialysis patients after attempted placement of AVFs or arteriovenous grafts (AVGs).

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Analogous Markov models were created, one each for AVF and AVG. Patients entered consideration at the time of first access creation, contemporaneous with dialysis initiation. Subsequent outcomes were determined probabilistically; transition probabilities, utilities, and costs were gathered from published sources. To ensure comparability between AVFs and AVGs, the timing and likelihood of access maturation were measured in a contemporary cohort of incident hemodialysis patients.

RESULTS

Mean (SD) overall survival was 39.2 (0.8) and 36.7 (1.0) months for AVFs and AVGs, respectively: difference (95% confidence interval [CI]) 2.6 (1.8, 3.3) months. Quality-adjusted survival was 36.1 (0.8) and 32.5 (0.9) quality-adjusted life months (QALMs) for AVFs and AVGs, respectively: difference (95% CI) 3.6 (2.8, 4.3) QALMs. The incremental cost-effectiveness ratio (95% CI) for AVFs relative to AVGs was $446 (-6023, 6994) per quality-adjusted life year saved.

CONCLUSIONS

AVFs are associated with greater overall and quality-adjusted survival than AVGs. Observed differences were much less pronounced than might be expected from existing literature, suggesting that prospective identification of patients at high risk for AVF maturational failure might enable improvements in health outcomes via individualization of access planning.

Infection-related hospitalizations in older patients with ESRD

BACKGROUND

Infection is an important cause of hospitalization and death in patients receiving dialysis. Few studies have examined the full range of infections experienced by dialysis patients. The purpose of this study is to examine types, rates, and risk factors for infection in older persons starting dialysis therapy.

STUDY DESIGN

Retrospective observational cohort study.

SETTING & PARTICIPANTS

The cohort was assembled from the US Renal Data System and included patients aged 65-100 years who initiated dialysis therapy between January 1, 2000, and December 31, 2002. Exclusions included prior kidney transplant, unknown dialysis modality, or death, loss to follow-up, or transplant during the first 90 days of dialysis therapy. Patients were followed up until death, transplant, or study end on December 31, 2004.

PREDICTORS

Baseline demographics, comorbid conditions, and serum albumin and hemoglobin levels.

OUTCOMES & MEASUREMENTS

Infection-related hospitalizations were ascertained using discharge International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. Hospitalization rates were calculated for each type of infection. The Wei-Lin-Weissfeld model was used to examine risk factors for up to 4 infection-related events.

RESULTS

119,858 patients were included, 7,401 of whom were on peritoneal dialysis therapy. During a median follow-up of 1.9 years, infection-related diagnoses were observed in approximately 35% of all hospitalizations. Approximately 50% of patients had at least 1 infection-related hospitalization. Rates (per 100 person-years) of pulmonary, soft-tissue, and genitourinary infections ranged from 8.3-10.3 in patients on peritoneal dialysis therapy and 10.2-15.3 in patients on hemodialysis therapy. Risk factors for infection included older age, female sex, diabetes, heart failure, pulmonary disease, and low serum albumin level.

LIMITATIONS

Use of ICD-9-CM codes, reliance on Medicare claims to capture hospitalizations, use of the Medical Evidence Form to ascertain comorbid conditions, and absence of data for dialysis access.

CONCLUSION

Infection-related hospitalization is frequent in older patients on dialysis therapy. A broad range of infections, many unrelated to dialysis access, result in hospitalization in this population.

The impact of treatment modality on infection-related hospitalization rates in peritoneal dialysis and hemodialysis patients

BACKGROUND AND OBJECTIVES

Infection is a major cause of morbidity and mortality in the dialysis population. This study compares the rates of infection-related hospitalization (IRH) in incident chronic dialysis patients initiating outpatient peritoneal dialysis (PD) and hemodialysis (HD).

METHODS AND PATIENTS

This was a retrospective cohort study at the dialysis program of a tertiary-care center in Toronto, Canada. Incident chronic dialysis patients that were eligible for both PD and HD and started outpatient dialysis between 1 January 2004 and 31 August 2008 were included. Dialysis modality was assigned at the start of outpatient dialysis treatment. All hospital admissions were reviewed and incidence of IRH was compared between PD and HD using Poisson regression.

RESULTS

Of 264 incident chronic dialysis patients, 168 (64%) were eligible for both treatment modalities: 71 (42%) started outpatient PD and 97 (58%) started outpatient HD. The unadjusted and adjusted incidence rate ratios (IRR) of IRH did not differ significantly between PD and HD: 1.23 [95% confidence interval (CI) 0.65-2.32, p=0.37] and 1.14 (95% CI 0.58-2.23, p=0.71) respectively. There was no difference between PD and HD in the risk of access loss (28% vs 35%, p=0.73), modality change (22% vs 0%, p=0.10), or death (17% vs 6%, p=0.60) following hospitalization for infection. Patients starting outpatient treatment on PD versus HD were more likely to be hospitalized for peritonitis (IRR 3.20, 95% CI 1.16-9.09; p=0.029) and there was a trend for fewer hospitalizations for bacteremia (IRR 0.19, 95% CI 0.028-1.30; p=0.091). The risk of IRH did not differ between PD and HD in the subgroup of patients that received adequate predialysis care (IRR 1.16, 95% CI 0.59-2.27; p=0.67) or when patients starting outpatient HD with a central venous catheter were excluded (IRR 1.52, 95% CI 0.53-4.37; p=0.44).

CONCLUSIONS

Patients that initiate outpatient peritoneal dialysis do not have a significantly increased risk of infection-related hospitalization compared to those that initiate outpatient hemodialysis.

Catheter-related infections via temporary vascular access catheters: a randomized prospective study

Temporary vascular access catheters (VACs) are important devices used in acute blood purification therapies. The aim of this study was to determine whether a catheterization duration of 2 weeks increased the risk of nosocomial complications when compared with a 1-week duration. Fifty-six patients with 90 double lumen VACs were randomly chosen, and received either 1- or 2-week catheterizations from operators experienced in the placement of such catheters at three sites such as the internal jugular, subclavian, or femoral vein. The characteristics of the VACs, including the sites, procedures, and lengths, were similar in both groups. No significant difference in the rate of catheter colonization was observed between the groups (14.6% vs 26.2%, P = 0.1371). No significant difference in the rate of catheter-related bloodstream infections was observed between the groups (2.1% vs 4.8%, P = 0.5967). Two-week indwelling did not increase the risk of infection compared with 1-week indwelling at any of the sites in critically ill patients.

Racial and gender differences in arteriovenous fistula use among incident hemodialysis patients

BACKGROUND

Arteriovenous fistula (AVF) use is reported to differ among racial and gender groups. We sought to identify risk factors associated with incident AVF and whether racial and gender differences in AVF use persist after controlling for these factors.

METHODS

We evaluated 28,712 incident adult hemodialysis patients (age ≥ 18) from five ESRD networks starting dialysis between June 1, 2005 and May 31, 2006. Data were obtained from the Center for Medicaid and Medicare Services 2728 form.

RESULTS

Incident AVF use was reported for 11% of black and 12% of white patients [OR = 0.89 (95% CI: 0.83, 0.96)], and for 9% of females and 13% of males [OR = 0.66 (0.62-0.71)]. After adjusting for facility clustering, blacks were as likely as whites to use an AVF [OR = 1.00 (0.92-1.09)], while gender differences persisted [OR = 0.64 (0.59-0.69)]. Compared to patients with no renal care prior to dialysis initiation, incident AVF use was 16-fold greater among those with ≥ 12 months of nephrology care [OR = 15.99 (13.25-19.29)], 9-fold greater among those with 6-12 months of care [OR = 9.00 (7.45-10.88)] and 7-fold greater among those with at least 6 months of care [OR = 7.13 (5.73-8.88)].

CONCLUSION

Racial, but not gender, differences in incident AVF use were eliminated after accounting for clustering within facilities.

PREFABL: predictors of failure of antibiotic locks for the treatment of catheter-related bacteraemia

BACKGROUND

Antibiotic lock (ABL) solutions can effectively treat catheter-related bacteraemia (CRB) without the need for catheter exchange. This approach does not increase secondary infectious complications. We evaluated the risk factors that contribute to failure when CRB is treated with ABLs and systemic antibiotics in paediatric haemodialysis patients.

METHODS

A retrospective chart review of 72 children on haemodialysis between January 2004 and June 2006 was performed. We evaluated risk factors for ABL treatment using patients' characteristics, CRB/catheter characteristics and patients' biochemical profiles. The first CRB of each catheter was included in the statistical analysis. Our end points were outcome at 2 weeks of treatment and at 6 weeks following treatment. Compound symmetry covariance structure was employed for statistical analysis.

RESULTS

We treated 149 CRB in 50 patients. The incidence was 3.4 CRB/1000 catheter days. Thirty CRB failed to be cleared with the use of ABL and systemic antibiotics at 2 weeks of treatment (30/149, 20 vs 80%, P < 0.001). Twenty-four of these catheters required exchange. Thirty-nine of the treated catheters got re-infected within the next 6 weeks (39/125, 31 vs 69%, P < 0.001). CRB aetiology was the only statistically significant independent variable for 2-week outcome (P = 0.033). Coagulase-negative Staphylococcus CRB had higher odds of being cleared at 2 weeks compared with other CRB aetiologies. For the 6-week outcome, the statistically significant independent variables in the final model included age (P = 0.048) and serum phosphorous level (P < 0.001). Younger age and higher serum phosphorous levels were independent risk factors for failure at 6 weeks with re-infection. Area under the receiver operating characteristic (ROC) curve for the model of the 2-week outcome was 0.736 with the percentage of correct predictions at 81.2%. Area under the ROC curve for the model of the 6-week outcome was 0.689 with the percentage of correct predictions at 75.5%.

CONCLUSIONS

CRB can effectively be treated with ABLs and systemic antibiotics. CRB aetiology is the only independent variable of early treatment failure. Younger age and higher serum phosphorous levels are independent risk factors for re-infection at 6 weeks.

Prophylaxis of catheter-related bacteremia using tissue plasminogen activator-tobramycin locks

This retrospective study was designed to investigate the effectiveness of tissue plasminogen activator-tobramycin antibiotic lock solutions (TPA/tobra ABLs) for prophylaxis of catheter-related bacteremia (CRB) in high-risk children on long-term hemodialysis. During the first 6 months (Era 1), the high-risk group was defined. These patients received TPA/tobra ABL prophylaxis after every hemodialysis treatment for the next 6 months (Era 2). The prophylaxis regimen was applied once a week for the third 6-months period (Era 3). Primary endpoints were CRB and infection-free catheter survival. There were 16,412 catheter days, and 95 cases of CRB in 43 children. The incidence of CRB was 5.8/1,000 catheter days. Significant decrease in the incidence of CRB was observed when prophylactic TPA/tobra ABL was used in the high-risk group (P = 0.0201). There was a tendency for less CRB when prophylactic ABL was applied after every hemodialysis session compared with once a week (P = 0.0947). The catheters in the high-risk group had shorter survival times than those in the average-risk group in Era 1 (P < 0.0001). However, both the overall and infection-free survival of the catheters in the high-risk group significantly improved while the patients were receiving TPA/tobra ABL prophylaxis, becoming similar to the outcomes of the catheters in the average-risk group and exhibiting statistically non-significant differences (P = 0.5571 and P = 0.9711, respectively). In conclusion, the TPA/tobra ABLs may effectively reduce the rate of CRB, and this may prolong both the overall and infection-free survival times of the catheters in the high-risk group.

Chlorhexidine-based antiseptic solutions effectively reduce catheter-related bacteremia

The aim of this retrospective study was to investigate if the application of chlorhexidine-based solutions (ChloraPrep) to the exit site and the hub of long-term hemodialysis catheters could prevent catheter-related bacteremia (CRB) and prolong catheter survival when compared with povidone-iodine solutions. There were 20,784 catheter days observed. Povidone-iodine solutions (Betadine) were used in the first half of the study and ChloraPrep was used in the second half for all the patients. Both groups received chlorhexidine-impregnated dressings at the exit sites. The use of ChloraPrep significantly decreased the incidence of CRB (1.0 vs 2.2/1,000 catheter days, respectively, P = 0.0415), and hospitalization due to CRB (1.8 days vs 4.1 days/1,000 catheter days, respectively, P = 0.0416). The incidence of exit site infection was similar for the two groups. Both the period of overall catheter survival (207.6 days vs 161.1 days, P = 0.0535) and that of infection-free catheter survival (122.0 days vs 106.9 days, P = 0.1100) tended to be longer for the catheters cleansed with ChloraPrep, with no statistical significance. In conclusion, chlorhexidine-based solutions are more effective for the prevention of CRB than povidone-iodine solutions. This positive impact cannot be explained by decreased number of exit site infections. This study supports the notion that the catheter hub is the entry site for CRB.

Efficacy of an intravenous proton pump inhibitor after endoscopic therapy with epinephrine injection for peptic ulcer bleeding in patients with uraemia: a case-control study

BACKGROUND

Patients with peptic ulcer bleeding and uraemia are prone to re-bleeding.

AIM

To compare the efficacy of an intravenous proton pump inhibitor in treating peptic ulcer bleeding in patients with uraemia and those without uraemia.

METHODS

High-risk peptic ulcer bleeding patients received endoscopic therapy with epinephrine (adrenaline) injection plus intravenous omeprazole (40 mg bolus followed by 40 mg infusion every 12 h) for 3 days. Re-bleeding, volume of blood transfusion, hospital stay, need for surgery, and mortality were analysed.

RESULTS

The uraemic group had similar 7-day re-bleeding rate (6/42, 14.29% vs. 6/46, 13.04%, P = 0.865) to that of non-uraemic patients, but more re-bleeding episodes beyond 7 days (4/42, 9.52% vs. 0/46, 0%, P = 0.032, OR [95% CI] = 1.105 [1.002-1.219]) and all-cause mortality (4/42 vs. 0/46 P = 0.032, OR [95% CI] = 1.105 [1.002-1.219]). The uraemic group also had more units of blood transfusion after endoscopic therapy (mean +/- s.d. 4.33 +/- 3.35 units vs. 2.15 +/- 1.65 units, P < 0.001), longer hospital stay (mean +/- s.d. 8.55 +/- 8.12 days vs. 4.11 +/- 1.60 days, P < 0.001) and complications during hospitalization (9/42 vs. 0/46, P = 0.001, OR [95% CI] = 1.273 [1.087-1.490]).

CONCLUSION

Endoscopic therapy with epinephrine injection plus an intravenous proton pump inhibitor can offer protection against early re-bleeding in uraemic patients with peptic ulcer bleeding, but has a limited role beyond 7 days.

Plasma gelsolin and circulating actin correlate with hemodialysis mortality

Plasma gelsolin (pGSN) binds actin and bioactive mediators to localize inflammation. Low pGSN correlates with adverse outcomes in acute injury, whereas administration of recombinant pGSN reduces mortality in experimental sepsis. We found that mean pGSN levels of 150 patients randomly selected from 10,044 starting chronic hemodialysis were 140 +/- 42 mg/L, 30 to 50% lower than levels reported for healthy individuals. In a larger sample, we performed a case-control analysis to evaluate the relationship of pGSN and circulating actin with mortality; pGSN levels were significantly lower in 114 patients who died within 1 yr of dialysis initiation than in 109 survivors (117 +/- 38 mg/L versus 147 +/- 42 mg/L, P < 0.001). pGSN levels had a graded, inverse relationship with 1-yr mortality, such that patients with pGSN < 130 mg/L experienced a > 3-fold risk for mortality compared with those with pGSN > or = 150 mg/L. The 69% of patients with detectable circulating actin had lower pGSN levels than those without (127 +/- 45 mg/L versus 141 +/- 36 mg/L, P = 0.026). Compared with patients who had elevated pGSN and no detectable actin, those with low pGSN levels and detectable actin had markedly increased mortality (odds ratio 9.8, 95% confidence interval 2.9 to 33.5). Worsening renal function correlated with pGSN decline in 53 subjects with CKD not on dialysis. In summary, low pGSN and detectable circulating actin identify chronic hemodialysis patients at highest risk for 1-yr mortality.