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

The HSP72 stress response of monocytes from patients on haemodialysis is impaired

BACKGROUND

Induction of heat shock proteins (HSP), i.e. of the major family member HSP70, is an important cytoprotective-resistance mechanism for monocytes/ macrophages (Mphi). Patients on haemodialysis present with a high infectious morbidity and enhanced carcinoma incidence. Renal insufficiency-related alteration of microbicidal and tumoricidal functions of Mphi, major effectors of the immune system, might promote these diseases.

METHODS

Freshly isolated Mphi from Sprague-Dawley rats 2 weeks after 5/6-nephrectomy and from patients on intermittent haemodialysis (IHD) were stimulated by heat shock (HS) and compared to stimulated Mphi of control rats or healthy volunteers (CTR). Expression of HSP72 (inducible HSP70) was assessed by RT-PCR, and/or flow cytometry. Apoptosis of Mphi was detected by flow cytometry (CD14/annexin V-labelling).

RESULTS

In rat Mphi, baseline HSP72 expression was similar in both groups, but its induction was significantly impaired in renal insufficiency (214 +/- 68% less HSP70-mRNA versus CTR, n = 6). In patients, HSF-1-mRNA and HSP72-mRNA/protein response to HS was significantly lower, but not affected by dialysis session itself. In parallel, apoptosis of Mphi of patients was enhanced (+83 +/- 29% constitutive apoptotic Mphi versus CTR, n = 8), and HS-dependent protection from apoptosis with and without serum depletion (48 h depletion: HS, +275 +/- 37% apoptotic Mphi versus CTR, n = 6; full medium: +166 +/- 62% versus CTR, n = 8, P < 0.05) was inferior.

CONCLUSIONS

Impaired HSP72 stress response of Mphi in patients on haemodialysis might contribute to the observed immune dysfunction and, therefore, to the increased susceptibility to infection and malignancy. Stress impairment is not restricted to uraemia but is already present in a rat model of chronic kidney disease.

Chronic unilateral neglect from focal meningoencephalitis lesions in an immune-compromised hemodialysis patient

Unilateral neglect (UN) is a disorder associated primarily with right-brain damage; it causes individuals to behave as if the contralesional half of their world has become unimportant or has simply ceased to exist. This is the first known case study to describe and measure UN caused by an infectious process, meningoencephalitis. The patient was immune compromised as a result of antirejection drugs following a kidney and pancreas transplant, as well as from a baseline vulnerability common to patients with hemodialysis. She was reassessed serially during hemodialysis treatments over 12 months and demonstrated improvement in some measures of UN but not in others. UN is a recognized nursing diagnosis and can be assessed, treated, and researched by nurses. Neuroscience nurses need to better understand and investigate UN to improve their own practice and the practice of other specialties.

Outcomes of critically ill patients with acute kidney injury and end-stage renal disease requiring renal replacement therapy: a case-control study

BACKGROUND

This study aimed to evaluate and compare the characteristics and outcomes of patients with end-stage renal disease (ESRD) with those of matched controls of patients with acute kidney injury (AKI) requiring renal replacement therapy.

METHODS

A case-control study was performed at the intensive care units (ICU) of three tertiary-care hospitals between December 2004 and September 2007. Patients were admitted with life-threatening complications and were matched for age and for severity of illness and organ dysfunctions. Conditional logistic regression was used to identify factors associated with hospital mortality.

RESULTS

A total of 54 patients with ESRD and 54 patients with AKI were eligible for the study and were well matched. In general, clinical characteristics were similar. Nonetheless, comorbidities were more frequent in patients with ESRD, and patients with AKI more frequently required mechanical ventilation. ICU (43% versus 20%, P = 0.023) and hospital (50% versus 24%, P = 0.010) mortality rates were higher in patients with AKI. In addition, patients with AKI experienced longer ICU and hospitals stays. The SAPS II score had a regular ability in discriminating survivors and non-survivors, and tended to underestimate mortality in patients with AKI and overestimate in patients with ESRD. When all patients were evaluated, older age [OR = 1.05 (95% CI, 1.01-1.09)], poor chronic health status [OR = 3.90(1.19-12.82)] and number of associated organ failures [OR = 4.44(1.97-10.00)] were the main independent predictors of mortality. After adjusting for those covariates, ESRD was still associated with a lower probability of death [OR = 0.17 (0.06-0.050)].

CONCLUSIONS

ESRD patients with life-threatening complications had significantly better outcome than AKI patients.

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.

Status of initiating pattern of hemodialysis: a multi-center study

This study was to evaluate the status of initiating pattern of hemodialysis (HD). Five hundred-three patients in 8 University Hospitals were included. Presentation mode (planned vs. unplanned), and access type (central venous catheters [CVC] vs. permanent access) at initiation of HD were evaluated, and the influence of predialysis care on determining the mode of HD and access type was also assessed. Most patients started unplanned HD (81.9%) and the most common initial access type was CVC (86.3%). The main reason for unplanned HD and high rate of CVC use was patient-related factors such as refusal of permanent access creation and failure to attend scheduled clinic appointments. Predialysis care was performed in 57.9% of patients and only 24.1% of these patients started planned HD and 18.9% used permanent accesses initially. Only a minority of patients initiated planned HD with permanent accesses in spite of predialysis care. To overcome this, efforts to improve the quality of predialysis care are needed.

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.

Catheter-related mortality among ESRD patients

Hemodialysis access-related complications remain one of the most important sources of morbidity and cost among persons with end-stage renal disease, with total annual costs exceeding $1 billion annually. In this context, the creation and maintenance of an effective hemodialysis vascular access is essential for safe and adequate hemodialysis therapy. Multiple reports have documented the type of vascular access used for dialysis and associated risk of infection and mortality. Undoubtedly, the central venous catheter (CVC) is associated with the greatest risk of infection-related and all-cause mortality compared with the autogenous arteriovenous fistula (AVF) or synthetic graft (AVG). The AVF has the lowest risk of infection, longer patency rates, greater quality of life, and lower all-cause mortality compared with the AVG or CVC. It is for these reasons that the National Kidney Foundation's Kidney Disease Outcome Quality Initiative Clinical Practice Guidelines for Vascular Access recommend the early placement and use of the AVF among at least 50% of incident hemodialysis patients. This report presents catheter-related mortality and calls for heightened awareness of catheter-related complications.

[Dialin: infection surveillance network for haemodialysis patients. First results]

AIM AND BACKGROUND

To show results of the first year of an infection surveillance network for haemodialysis patients (Dialin). In order to improve the security and quality of care, six haemodialysis centers have organized an infection watching network. The purpose of the network is to compare of the watching results between centers. This comparison includes vascular access infection (VAI), bacteraemia and C viral hepatitis. The heterogeneous pattern has been also taken into account. SURVEY TYPE: Multicenter prospective permanent survey.

POPULATION

Six hundred and sixty-four haemodialyzed chronic patients, followed during one year (2005), in six voluntary haemodialysis centers. This survey has based on 71,688 treatment sessions corresponding to 6257.5 months of haemodialysis (HM).

METHODS

As with the heterogeneity among centers, the acquired infection standardized ratios (observed/expected) (AISR) and 95% confidence interval are computed with Cox model which includes confounding factors found in literature or in the preliminary stage of the survey.

RESULTS

VAI crude rate was 0.47 per 100HM, 0.10 per 1000 native fistulae utilisation days, 0.45 per 1000 days of prosthetic graft utilisation and 0.44 per 1000 days of catheter utilisation. Bacteraemia crude incidence rate was 0.69 per 100HM, 0.02 per 1000 days of native fistulae utilisation, 0.00 per 1000 days of prosthetic graft utilisation and 0.39 per 1000 days of catheter utilisation. No new case of C viral hepatitis was found. Prevalence rate at the beginning of the survey was 5.3% (35 over 664). Two centers had a significantly high AISR for VAI and two centers had a significantly low AISR for VAI. One center had a significantly high AISR for bacteraemia and one center had a significantly low AISR for bacteraemia.

CONCLUSIONS

The first year of Dialin running demonstrates the importance of standardised surveillance method in VAI and bacteraemia surveillance but not for viral hepatitis.

Associations of dialysis modality and infectious mortality in incident dialysis patients in Australia and New Zealand

BACKGROUND

The aim of the present investigation is to compare rates, types, causes, and timing of infectious death in incident peritoneal dialysis (PD) and hemodialysis (HD) patients in Australia and New Zealand.

STUDY DESIGN

Observational cohort study using the Australian and New Zealand Dialysis and Transplant Registry data.

SETTING & PARTICIPANTS

The study included all patients starting dialysis therapy between April 1, 1995, and December 31, 2005.

PREDICTOR

Dialysis modality.

OUTCOMES & MEASUREMENTS

Rates of and time to infectious death were compared by using Poisson regression, Kaplan-Meier, and competing risks multivariate Cox proportional hazards model analyses.

RESULTS

21,935 patients started dialysis therapy (first treatment PD, n = 6,020; HD, n = 15,915) during the study period, and 1,163 patients (5.1%) died of infectious causes (PD, 529 patients; 7.6% versus HD, 634 patients; 4.2%). Incidence rates of infectious mortality in PD and HD patients were 2.8 and 1.7/100 patient-years, respectively (incidence rate ratio PD versus HD, 1.66; 95% confidence interval [CI], 1.47 to 1.86). After performing competing risks multivariate Cox analyses allowing for an interaction between time on study and modality because of identified nonproportionality of hazards, PD consistently was associated with increased hazard of death from infection compared with HD after 6 months of treatment (<6 months hazard ratio [HR], 1.08; 95% CI, 0.76 to 1.54; 6 months to 2 years HR, 1.31; 95% CI, 1.09 to 1.59; 2 to 6 years HR, 1.51; 95% CI, 1.26 to 1.80; >6 years HR, 2.76; 95% CI, 1.76 to 4.33). This increased risk of infectious death in PD patients was largely accounted for by an increased risk of death caused by bacterial or fungal peritonitis.

LIMITATIONS

Patients were not randomly assigned to their initial dialysis modality. Residual confounding and coding bias could not be excluded.

CONCLUSIONS

Dialysis modality selection significantly influences risks, types, causes, and timing of fatal infections experienced by patients with end-stage kidney disease in Australia and New Zealand.

Vascular access-related infections: definitions, incidence rates, and risk factors

Hemodialysis is associated with a high risk of morbidity and mortality, often caused by infections. Infections account for approximately 15% of all deaths in this patient population (the second leading cause after cardiovascular events) and for about one-fifth of admissions. Approximately one-fourth of infection-related admissions are caused by dialysis-associated peritonitis or vascular access infection that may lead to such significant complications as endocarditis or death. Published studies that assessed the determinants of hemodialysis-related vascular infections reported inconsistent findings. Variations in the definitions of infection among these studies despite the existence of standard guidelines proposed by at least 3 major work groups may explain, at least in part, these inconsistencies. A comprehensive in-depth review of those studies is needed to examine the inconsistencies in the published results. We first revised the existing vascular access-related infection definitions, then conducted a narrative review of the published literature that examined predictors of vascular access-related infections, highlighting the heterogeneity in methods and findings. Better understanding of the risk factors for vascular access-related infections may inform efficacious prevention strategies and lead to early detection of infections and improved patient care.

Epidemiology of acute infections among patients with chronic kidney disease

The objectives of this review were (1) to review recent literature on the rates, risk factors, and outcomes of infections in patients who had chronic kidney disease (CKD) and did or did not require renal replacement therapy; (2) to review literature on the efficacy and use of selected vaccines for patients with CKD; and (3) to outline a research framework for examining key issues regarding infections in patients with CKD. Infection-related hospitalizations contribute substantially to excess morbidity and mortality in patients with ESRD, and infection is the second leading cause of death in this population. Patients who have CKD and do not require renal replacement therapy seem to be at higher risk for infection compared with patients without CKD; however, data about patients who have CKD and do not require dialysis therapy are very limited. Numerous factors potentially predispose patients with CKD to infection: advanced age, presence of coexisting illnesses, vaccine hyporesponsiveness, immunosuppressive therapy, uremia, dialysis access, and the dialysis procedure. Targeted vaccination seems to have variable efficacy in the setting of CKD and is generally underused in this population. In conclusion, infection is a primary issue when caring for patients who receive maintenance dialysis. Very limited data exist about the rates, risk factors, and outcomes of infection in patients who have CKD and do not require dialysis. Future research is needed to delineate accurately the epidemiology of infections in these populations and to develop effective preventive strategies across the spectrum of CKD severity.

Serum phosphate levels and risk of infection in incident dialysis patients

BACKGROUND AND OBJECTIVES

Hyperphosphatemia is highly prevalent in dialysis patients and may be associated with immune dysfunction. The association of serum phosphate level with infection remains largely unexamined.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In an incident cohort of 1010 dialysis patients enrolled from 1995 to 1998 and treated in 80 US clinics, the association of phosphate level (low <3.5; normal 3.5 to 5.5; high >5.5 mg/dl) at baseline and during follow-up with the risk for incident inpatient and outpatient infection-related events was examined. Infectious events were identified from US Renal Data System data (mean follow-up 3.3 yr). Incidence rate ratios for all infections, sepsis, respiratory tract infections, and osteomyelitis were obtained using multivariable Poisson models, adjusting for potential confounders (age, race, gender, smoking, comorbidity, and laboratory values).

RESULTS

Infections of any type (n = 1398) were more frequent among patients with high phosphate levels at baseline, relative to normal; this association was not changed by adjustment for parathyroid hormone level. Similarly, high versus normal baseline phosphate was associated with increased risk for sepsis and osteomyelitis but not respiratory tract infections. Associations with calcium were generally NS, and results with calcium-phosphate product mirrored the phosphate results.

CONCLUSIONS

High phosphate levels may be associated with increased risk for infection, contributing further to the rationale for aggressive management of hyperphosphatemia in dialysis patients.

Variability in reasons for hemodialysis catheter use by race, sex, and geography: findings from the ESRD Clinical Performance Measures Project

BACKGROUND

Race, sex, and geographic differences in hemodialysis vascular access use have been reported, but differences in reasons for catheter use have not been assessed.

STUDY DESIGN

Cross-sectional.

SETTING & PARTICIPANTS

Data obtained from the 2005 Centers for Medicare & Medicaid Services End-Stage Renal Disease Clinical Performance Measures Project for adult hemodialysis patients.

PREDICTORS

Race, sex, and geographic region.

OUTCOMES & MEASUREMENTS

Reasons for catheter use were categorized as short term and long term. Race, sex, and geographic associations with reasons were assessed by using bivariate analyses and multivariate logistic regression.

RESULTS

Of 8,479 hemodialysis patients, 3,302 (39%) used a fistula, 2,725 (32%) used a graft, and 2,299 (27%) used a catheter. We placed 857 patients with a catheter (37%) in the short-term-reason cohort and 1,404 (61%) in the long-term-reason cohort, and 38 (2%) lacked information to be placed. Reasons for catheter use were independently associated with race, sex, and geographic region. Whites were 43%, 49%, and 34% less likely than African Americans to use a catheter because of graft maturation, graft interruption, and all vascular access sites exhausted and 70% and 40% more likely because of fistula maturation and no fistula or graft surgically planned, respectively. Men were 50% less likely than women to use a catheter because of graft interruption and 80% more likely because of fistula maturation. Geographic end-stage renal disease network was associated with catheter use because of fistula maturation (P = 0.03), no fistula or graft surgically created (P < 0.001), and no fistula or graft surgically planned (P = 0.05).

LIMITATIONS

The cross-sectional study design precludes our ability to assess trends over time in reasons for catheter use. Associations were assessed for a limited set of variables.

CONCLUSION

Race, sex, and geographic differences in reasons for hemodialysis catheter use exist. Understanding these differences may aid in developing strategies to decrease catheter initiation rates.

Infective endocarditis in haemodialysis patients: 16-year experience at one institution

Objectives. To ascertain the characteristics, outcomes and correlates of mortality in chronic haemodialysis patients with confirmed infective endocarditis (IE).

Methods. Patients were identified by computerized discharge diagnosis and chart review of admissions to Saint Louis University hospital from January 1990 through January 2006. Modified Duke Criteria were retrospectively applied to confirm the diagnosis of IE. Survivors and non-survivors were compared to identify clinical correlates of IE mortality.

Results. We identified 59 patients with IE who had received dialysis for a mean duration of 52.9 ± 58.0 months prior to IE diagnosis. Dialysis access comprised 28 (47.5%) catheters, 26 (44.1%) arteriovenous grafts, 3 (5.1%) arteriovenous fistulas and 2 (3.4%) life sites. The causative organisms were MRSA in 15 (25%), MSSA 12 (20%), S. Epidermidis 10 (17%), Enterococci 8 (14%), multi-organism 6 (10%), gram negative 2 (3%) and VRE 1 (2%). Valves involved were mitral valve in 37 (63%), aortic valve in 10 (17%), tricuspid valve in 3 (5%) and multiple valves in 8 (13%) cases. Patient mortality was 28.8% (n = 17) during hospitalization, 37.9% (n = 22) at 30 days and 63.1% (n = 36) at 1 year. In multivariable logistic regression, the adjusted odds ratio of in-hospital mortality was 3.6-fold higher in those with IE and arteriovenous grafts (P = 0.04, 95% CI 1.04–12.27) compared to other forms of dialysis access.

Conclusion. Mortality of IE remains high, despite the availability of potent antibiotics. Patients with arteriovenous grafts who develop IE may face increased risk for in-hospital mortality, perhaps reflecting difficulty eradicating endovascular infection if a graft is involved.

Comparison of early versus late use of antibiotic locks in the treatment of catheter-related bacteremia

BACKGROUND AND OBJECTIVES

This retrospective study compared the effectiveness of the timing of the antibiotic locks to clear catheter-related bacteremia in children on chronic hemodialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The early antibiotic lock group received antibiotic locks along with systemic antibiotics from the very beginning of catheter-related bacteremia. The late antibiotic lock group was given only systemic antibiotics initially, and antibiotic locks were used late in the infection if the catheter-related bacteremia could not be cleared after resolution of symptoms.

RESULTS

There were 264 catheter-related bacteremias in 79 children during 6 yr of observation. Early antibiotic locks were able to clear catheter-related bacteremia and resolve the symptoms more effectively without the need for catheter exchange when compared with late antibiotic locks. A total of 84 catheter-related bacteremias required wire-guided exchange of the catheters. Late antibiotic locks required wire-guided catheter exchange more frequently than the early antibiotic locks. The post-catheter-related bacteremia infection-free survival of the catheters after wire-guided exchange were significantly longer than those of both antibiotic lock groups. Recurrence of catheter-related bacteremia within 45 d after wire-guided exchange occurred at similar rates compared with the antibiotic lock groups.

CONCLUSION

Antibiotic locks are significantly more effective in clearing catheter-related bacteremia when used early in infection, diminishing the need for catheter exchange. Wire-guided exchange has a late-onset advantage for infection-free survival compared with catheter in situ treatment. The recurrence rates in the first 45 d after catheter-related bacteremia are similar regardless of the treatment strategy.

Septic arthritis in haemodialysis patients: a seven-year multi-centre review

PURPOSE

To determine relevant demographics, clinical features, and outcomes for septic arthritis in patients on haemodialysis for end-stage renal failure.

METHODS

A multi-centre retrospective review was performed from 1999 to 2005.

RESULTS

15 cases were identified. The mean age of the patients at diagnosis was 67 (range, 23-89) years and 11 were male. All had multiple co-morbidities and additional risk factors for sepsis. The primary sources of sepsis were dialysis access-related (n=12), unknown in 2, and unrelated soft tissue infection in one. All patients presented with acute monoarticular symptoms; the knee joint was affected in 11 patients. The white cell count, neutrophil count, and C-reactive protein concentration were elevated in 10, 10, and 15 patients, respectively. All patients had positive synovial fluid cultures and blood cultures were positive in 14. Organisms isolated were all skin commensals, being staphylococcal in 13 and streptococcal in 2. Six patients had concomitant rheumatological disease (gout in 4, pseudogout in one, and rheumatoid arthritis in one). Two had urate crystals in the synovial fluid (noted by microscopy). All patients underwent antimicrobial therapy for a mean of 36 days, together with joint washouts and debridement. 12 patients were cured of infection; 2 developed chronic sepsis secondary to localised osteomyelitis; and one died of sepsis.

CONCLUSION

Septic arthritis is a potentially devastating condition. Early and aggressive joint lavage and debridement combined with appropriate antimicrobial therapy is imperative. A high index of suspicion is necessary in haemodialysis patients; the diagnosis of septic arthritis must be presumed until proven otherwise.

Treatment of catheter-related bacteremia with tissue plasminogen activator antibiotic locks

This retrospective study was completed to investigate the effectiveness of tissue plasminogen activator (TPA) antibiotic locks (ABL) along with systemic antibiotics (AB) to clear catheter-related bacteremia (CRB) in children on chronic hemodialysis. There were 76 CRBs in 37 children. CRBs were successfully cleared with AB/ABL in 63/76 (83%) cases. Ten of 76 (13%) CRBs were symptomatic at 48 h of treatment. These were seven polymicrobial, two gram-negative, and one Candida CRB. 13/76 (17%) episodes required catheter exchange, and all were wire-guided exchanges. TPA-ABL/AB cleared gram-positive and gram-negative CRBs significantly better than polymicrobial CRBs (p < 0.01). The infection-free survival and the rate of recurrence at 45 days was not statistically different between the TPA-ABL/AB group and the catheter-exchange group. If CRB was symptomatic at 48 h of treatment, recurrence at 6 weeks was more frequent with persistent use of TPA-ABL/AB (p < 0.05). There were no episodes of metastatic infections, catheter malfunction from occlusion, or catheter breakdown during the course of TPA-ABL treatments. In conclusion, TPA-ABL can be safely and effectively used in the management of CRB, increasing the probability of catheter survival and preserving the vascular access site. With the exception of polymicrobial CRB, there is no disadvantage in using TPA-ABL/AB over catheter exchange, as the infection-free survival and the rate of recurrence are comparable.

[Isolation of filamentous fungi from water used in a hemodialysis unit]

Despite the relative frequency of opportunistic fungal infections among hemodialysis patients, the reservoirs for these microorganisms in the environment remain unknown, although some recent studies have made correlations with the water supply as their source. The objective of the present study was to monitor the mycological quality of the water system of a hemodialysis unit in the interior of the State of São Paulo, Brazil, over the period from April to July 2006. Fifteen samples of 1000 ml were collected from seven water distribution points using the membrane filtration technique (0.45 microm). A total of 116 filamentous fungus specimens were isolated, including 47 Trichoderma sp (40.5%), 29 Cladosporium sp (25%), 16 Aspergillus sp (13.8%) and 11 Fusarium sp (9.5%). The results suggest that the water supply for hemodialysis units should also be monitored for mycological contamination, and that effective prophylactic measures should be adopted for minimizing the exposure of these immunodeficient patients to contaminated water sources in the environment.

Low CR1 (C3b receptor) level on erythrocytes is associated with poor prognosis in hemodialysis patients

BACKGROUND

Erythropoietin in patients under dialysis treatment for renal failure is low which induces anemia. Treatment with recombinant erythropoietin (rEPO) has been used routinely as a supplement treatment for these patients. Immune complexes (IC) react with complement and bind to CR1 on erythrocytes (E-CR1), and are transported to the liver and/or spleen where IC removal and degradation occurs. The erythrocytes then return to circulation where they bind to additional IC. There are some patients whose E-CR1 expression is low with chronic anemia in spite of rEPO treatment. We hypothesized that in hemodialysis (HD) patients altered host defense against infection is associated with low levels of E-CR1. We examined if low E-CR1 in dialysis patients constitutes a risk factor for reduced host defense and poor outcome.

METHODS

In 95 HD patients, E-CR1 was quantified using a monoclonal E-CR1 antibody and FACS analysis followed by clinical course studies for 5 years.

RESULTS

The patients were divided into three groups by E-CR1 level. Percent survival for the low E-CR1 group (53.3%) was significantly lower than the high E-CR1 group (86.4%) (p < 0.01). There were more hepatitis C virus-positive patients within the low E-CR1 group (27.3%) than in the high E-CR1 group (4.7%) (p < 0.05). Furthermore, 10 patients with the lowest E-CR1 levels had severe complications, notably infection at an arteriovenous fistula.

CONCLUSION

A reduced E-CR1 level might be a risk factor for reduced host defense and can be used as a predicting factor for poor prognosis in a HD patient.

A prospective study on incidence of bacterial infections in portuguese dialysis units

BACKGROUND

Viral infection has been the main epidemiologic concern in the hemodialysis unit; however, bacterial infection is responsible for more than 30% of all causes of morbidity and mortality in our patients, vascular access infection being the culprit in 73% of all bacteremias.

METHODS

A prospective multicenter cohort study of bacterial infections incidence, conducted from January to July 2004 in five hemodialysis units, to record and track bacterial infections, using a validated database from CDC's Dialysis Surveillance Network Program.

RESULTS

4,501 patient-months (P-M) were surveilled, being dialyzed through a native fistula (AVF) in 60.6%, a graft (PTFE) in 31.3%, a tunneled catheter (TC) in 7.6%, and a transient catheter (C) in 0.5%. As target events, we registered 166 hospitalizations - 3.7/100 P-M (2.2/100 P-M in patients with AVF, 4 in PTFE, 9.9 in TC, and 19 in C), and 182 intravenous antibiotic courses. Of these 182 antibiotic treatments, 47.8% included vancomycin, only 30% had blood cultures drawn pretreatment, and only 36% were positive. We recorded 98 infections at the vascular access site 2.18/100 P-M (0.95 in AVF, 1.6 in PTFE, 12.6 in TC, and 42.85 in C) and 2.13 infections/100 P-M at other sites. The isolated microorganisms were Staphylococcus epidermidis in 40.1%, Staphylococcus aureus in 30.1%, Pseudomonas in 13.3%, and Escherichia coli in 3.3%. Although we found a diversity of practice patterns, the number of target events (8.4/100 P-M) and the bacterial infections incidence (4.31/100 P-M) were remarkably homogeneous in the five centers.

CONCLUSION

(1) High incidence of bacterial infections, causing major morbidity; (2) infectious risk is vascular access type-dependent, with dramatic rise in catheters; (3) underutilization of blood cultures to orient diagnosis and therapy, and (4) high rates of vancomycin prescription.

Catheter survival and comparison of catheter exchange methods in children on hemodialysis

This retrospective study was done to compare the infection-free and overall survival of first and subsequent tunneled cuffed hemodialysis catheters in children. Subsequent catheters were exchanged by two different methods (a) removal and replacement (R&R), or (b) wire-guided exchange (WGE) using the same tunnel and vessel. The study involved 59 children (27 male, 32 female; mean age 13.9 +/- 4.6 years) undergoing maintenance hemodialysis in a pediatric unit over a period of 60 months. From a total of 175 catheters (57 first catheters, 81 WGE, 37 R&R) and 38,888 catheter days, 74/175 (42%) catheters were exchanged because of catheter-related bacteremia (CRB) and 43/175 (25%) for malfunction or cuff extrusion. One-year survival rates for first and consecutive catheters was 26% and 21%, respectively. The overall survival of first catheters, and those exchanged by WGE and R&R for both infectious and non-infectious reasons, was not statistically different. However, infection-free survival of first catheters was significantly prolonged in comparison with that of subsequent catheters (P < 0.001). The infection-free survival and the overall survival were not affected by etiology of primary disease, gender, serum albumin, or hemoglobin. Overall catheter survival increased with age >10 years. There was a significant association between gram-negative and polymicrobial CRB and requirement for R&R (P < 0.02). Our findings suggest that WGE is safe in a clinically stable child if the tunnel and the exit site are not infected and has the potential benefit of preserving the vascular access site. The shorter infection-free survival in subsequent catheters suggests a cumulative disadvantage with prolonged catheter use.

Balancing Fistula First With Catheters Last

The success of Fistula First nationwide has been accompanied by an unplanned increase in hemodialysis catheters. Complications related to prolonged hemodialysis catheter use include increased morbidity, mortality, and cost. We hypothesize that the national focus on increasing fistulas may have inadvertently diverted attention away from initiatives to decrease dependence on hemodialysis catheters. Based on a synthesis of guidelines, reviews, published evidence, and the authors' opinions, we propose that the national vascular access initiative be revised to have a dual goal of Fistula First and "Catheters Last." These goals are not mutually exclusive, but rather complementary. We recommend a systematic refocus on interventions that not only increase fistulas, but help avoid extended catheter use. Clearly, the ideal practice for hemodialysis vascular access remains early placement of fistulas with enough maturation time such that they can be used for initiating long-term hemodialysis therapy when the need arises. To effect this change, a reimbursement policy covering the costs associated with permanent access placement before the need for dialysis is essential. Individualized patient management strategies may consider such innovative approaches as initiating patients on peritoneal dialysis therapy or using nonautogenous grafts as bridge accesses in lieu of catheters. For patients who are dialyzing using catheters, immediate active planning for permanent access placement and removal of the catheter is necessary. In the same vein as Fistula First, the renal community should once again be galvanized in working together toward controlling the catheter epidemic in our dialysis population.

Single-UseversusReusable Dialyzers: The Known Unknowns

The practice of reusing dialyzers has been widespread in the United States for decades, with single use showing signs of resurgence in recent years. Reprocessing of dialyzers has traditionally been acknowledged to improve blood-membrane biocompatibility and prevent first-use syndromes. These proposed advantages of reuse have been offset by the introduction of more biocompatible membranes and favorable sterilization techniques. Moreover, reuse is associated with increased health hazard from germicide exposure and disposal. Some observational studies have also pointed to an increased mortality risk with dialyzer reuse, and the potential for legal liability is another concern. The desire to save cost is the major driving force behind the continued practice of dialyzer reuse in the United States. It is imperative that future research focus on the environmental consequences of dialysis, including the need for more optimal management of disinfectant-related waste with reuse, and solid waste with single use. The dialysis community has a responsibility to explore ways to mitigate environmental consequences before single-use and a more frequent dialysis regimen becomes a standard practice in the United States.

Use of Antimicrobial Catheter Lock Solutions to Prevent Catheter-Related Bacteremia

Catheter-related bacteremia is an important source of morbidity and mortality in hemodialysis patients. A number of well-designed, controlled, prospective trials using antimicrobial catheter lock solutions to prevent catheter-related bacteremia have shown a dramatic, statistically significant decrease in not only infection but also mortality related to catheter-related bacteremia. Despite evidence of significant benefit, these locks are not routinely used in the United States. This review describes the epidemic problem of catheter-related bacteremia, reviews recent clinical trials with antimicrobial catheter lock solutions, and discusses current options and potential indications for catheter lock solutions in the hemodialysis population.

Increased Complication Rates of Cardiac Rhythm Management Devices in ESRD Patients

BACKGROUND

Patients with end-stage renal disease (ESRD) have a high incidence of sudden cardiac death and may benefit from implantable cardioverter defibrillators (ICDs). However, ESRD also may predispose patients to device-related complications, potentially offsetting some of the benefits of prophylactic ICD placement. The purpose of this study is to compare the incidence of complications after cardiac rhythm management device (CRMD) implantation in patients with and without ESRD.

METHODS

An observational study was performed on 41 patients with ESRD and 123 controls without ESRD who had a CRMD (permanent pacemaker or ICD) implanted at a single institution from 1998 to 2005. Controls were matched for age, sex, type of device, and calendar year of device implantation. Primary and secondary end points were any complication and complications requiring intervention, respectively.

RESULTS

23 complications occurred in 16 of 41 patients with ESRD (39%) versus 13 complications in 13 of 123 matched controls (11%; P < 0.001). Major complications occurred in 29% of patients with ESRD versus 5% of controls (P < 0.001), whereas minor complications occurred in 17% and 6%, respectively (P < 0.03). Hematoma, thrombosis, and device-related complications, including elevated defibrillation thresholds, were more common in patients with ESRD (P < 0.05 for all), and there also was a nonsignificant trend toward greater infection risk (P = 0.1). There were no fatal complications in either group.

CONCLUSIONS

Patients with ESRD had greater complication rates after CRMD implantation compared with matched controls, but these complications did not result in death. These results should be considered when evaluating patients with ESRD for prophylactic CRMD implantation, but do not support withholding such therapy.

Central venous catheter-related bacteremia in chronic hemodialysis patients: epidemiology and evidence-based management

Central venous catheter-related blood stream infection (CRBSI) is a major cause of morbidity and mortality in patients with end-stage renal disease treated with chronic hemodialysis. Risk factors include Staphylococcus aureus nasal colonization, longer duration of catheter use, previous bacteremia, older age, higher total intravenous iron dose, lower hemoglobin and serum albumin levels, diabetes mellitus and recent hospitalization. Symptoms that raise clinical suspicion of bacteremia in chronic hemodialysis patients are fevers and chills. When CRBSI is suspected, blood cultures should be obtained and empirical therapy with broad spectrum intravenous antibiotics initiated. The diagnosis of CRBSI is confirmed by isolation of the same microorganism from quantitative cultures of both the catheter and the peripheral blood of a patient that has clinical features of infection without any other apparent source. Gram-positive cocci, predominantly S. epidermidis and S. aureus, cause bacteremia in two-thirds of cases. Among the various approaches to management of CRBSI, removal and delayed replacement of the catheter, catheter exchange over a guidewire in selected patients, and the use of antimicrobial/citrate lock solutions have all been found to be promising for treatment and/or prevention; however, resolution of issues regarding selection, dose, duration and emergence of antibiotic-resistant organisms with chronic use of antibiotic lock solutions, as well as the safety of long-term use of trisodium citrate lock solutions, await further randomized, multicenter trials involving larger samples of hemodialysis patients.

Prevention of sepsis during the transition to dialysis may improve the survival of transplant failure patients

Dialysis patients are at risk for sepsis, and the risk may be even higher among transplant failure patients because of previous or ongoing immunosuppression. The incidence and the consequences of sepsis as defined by International Classification of Diseases, Ninth Revision, Clinical Modification hospital discharge diagnoses codes were determined among 5117 patients who initiated dialysis after transplant failure between 1995 and 2004 in the United States. The overall sepsis rate was 11.8 per 100 patient years (95% confidence interval [CI] 11.5 to 12.1). Sepsis was highest in the first 6 mo after transplant failure (35.6 per 100 patient years [95% CI 29.4 to 43.0] between 0 to 3 mo after transplant failure; 19.7 per 100 patient years [95% CI 17.2 to 22.5] between 3 to 6 mo after transplant failure). In comparison, the sepsis rate among incident dialysis patients between 3 and 6 mo after dialysis initiation was 7.8 per 100 patient years (95% CI 7.3 to 8.3), whereas the sepsis rate among transplant recipients between 3 and 6 mo after transplantation was 5.4 per 100 patient years (95% CI 4.9 to 5.9). Patients who were > or =60 yr, obese patients, patients with diabetes, and patients with a history or peripheral vascular disease or congestive heart failure were at risk for sepsis. Transplant nephrectomy was not associated with septicemia. The role of continued immunosuppression and vascular access creation was not assessed and should be addressed in future studies. In a multivariate analysis, patients who were hospitalized for sepsis had an increased risk for death (hazard ratio 2.93; 95% CI 2.64 to 3.24; P < 0.001). Strategies to prevent sepsis during the transition from transplantation to dialysis may improve the survival of patients with allograft failure.

Determinants of serum albumin concentration analyzed in a large cohort of patients on maintenance hemodialysis

OBJECTIVE

Serum albumin concentration is a powerful predictor of mortality in patients on chronic hemodialysis (CHD). This study sought to investigate variables associated with serum albumin concentration.

DESIGN AND STUDY POPULATION

Cross-sectional study in prevalent chronic hemodialysis patients treated at the Renal Research Institute between July 1, 2005 and October 31, 2005. A total of 4,798 (2,199 females) patients were studied.

MAIN OUTCOME MEASURES

Univariate and multivariate relationships of serum albumin concentration with age, sex, race (black, white, other), vascular access type (arteriovenous fistula/graft, catheter), white blood cells, neutrophils, lymphocytes, equilibrated normalized protein catabolic rate (enPCR), dialysis efficacy (eKdrt/V), hemoglobin, phosphate, bio-intact parathyroid hormone [bioPTH], creatinine, alanine aminotransferase (ALT), and aspartate aminotransferase (AST).

RESULTS

Age, access type, and variables of 3 domains, namely, nutrition (enPCR; creatinine), eKdrt/V, and inflammation (white blood cells; neutrophil:lymphocyte ratio; hemoglobin), were related to serum albumin. It is interesting to note that AST was the strongest negative predictor of albumin levels.

CONCLUSION

In CHD patients, serum albumin concentration is defined by a complex interaction of inflammation, nutrition, and dialysis efficacy. The relationship between AST and albumin deserves additional study.

Preserved leukocyte CD11b expression at the site of interstitial inflammation in patients with high-flux hemodiafiltration

The impact of high-flux hemodialysis on clinical outcomes remains controversial. We have previously shown that in vivo transmigrated leukocytes from patients with low-flux bioincompatible hemodialysis have an impaired capacity to upregulate CD11b at the site of interstitial inflammation. In the present study, we investigated the in vivo capacity of transmigrated monocytes and granulocytes to express CD11b at the site of interstitial inflammation in 10 patients on biocompatible high-flux hemodiafiltration or high-flux hemodialysis and 12 healthy subjects, and the in vitro response to a bacteria-related peptide (N-formyl-methionyl-leucyl-phenylalanine (fMLP)). Leukocyte formation of hydrogen peroxide (H(2)O(2)) and leukocyte apoptosis were also studied. In patients, both monocytes and granulocytes had a preserved capacity to express CD11b following in vivo transmigration to sites of interstitial inflammation, compared with cells from healthy subjects. Furthermore, monocytes and granulocytes from patients showed a preserved ability to respond to challenge with fMLP in the extravascular milieu. The intracellular killing capacity of leukocytes (H(2)O(2) production) in the interstitium was similar as of cells from healthy subjects both before and after stimulation with fMLP. Following maximal receptor independent stimulation (phorbol 12-myristate 13-acetate), leukocytes from patients showed lower H(2)O(2) production at the site of intense inflammation, compared with cells from healthy subjects. Finally, leukocyte apoptosis in interstitial inflammation was similar in patients and healthy subjects. We conclude that in vivo transmigrated leukocytes from patients on biocompatible high-flux hemodiafiltration or high-flux hemodialysis have a preserved capacity to express CD11b at the site of interstitial inflammation. This may have important biological implications.

Attainment of clinical performance targets and improvement in clinical outcomes and resource use in hemodialysis care: a prospective cohort study

BACKGROUND

Clinical performance targets are intended to improve patient outcomes in chronic disease through quality improvement, but evidence of an association between multiple target attainment and patient outcomes in routine clinical practice is often lacking.

METHODS

In a national prospective cohort study (ESRD Quality, or EQUAL), we examined whether attainment of multiple targets in 668 incident hemodialysis patients from 74 U.S. not-for-profit dialysis clinics was associated with better outcomes. We measured whether the following accepted clinical performance targets were met at 6 months after study enrollment: albumin (> or =4.0 g/dl), hemoglobin (> or =11 g/dl), calcium-phosphate product (<55 mg2/dl2), dialysis dose (Kt/V> or =1.2), and vascular access type (fistula). Outcomes included mortality, hospital admissions, hospital days, and hospital costs.

RESULTS

Attainment of each of the five targets was associated individually with better outcomes; e.g., patients who attained the albumin target had decreased mortality [relative hazard (RH) = 0.55, 95% confidence interval (CI), 0.41-0.75], hospital admissions [incidence rate ratio (IRR) = 0.67, 95% CI, 0.62-0.73], hospital days (IRR = 0.61, 95% CI, 0.58-0.63), and hospital costs (average annual cost reduction = 3,282 dollars, P = 0.002), relative to those who did not. Increasing numbers of targets attained were also associated, in a graded fashion, with decreased mortality (P = 0.030), fewer hospital admissions and days (P < 0.001 for both), and lower costs (P = 0.029); these trends remained statistically significant for all outcomes after adjustment (P < 0.001), except cost, which was marginally significant (P = 0.052).

CONCLUSION

Attainment of more clinical performance targets, regardless of which targets, was strongly associated with decreased mortality, hospital admissions, and resource use in hemodialysis patients.

Neutrophil dysfunction and infection risk in end-stage renal disease

Infections are still a major cause of morbidity and mortality in end-stage renal disease (ESRD) patients. The susceptibility of ESRD patients to infections is typically ascribed to the immunodeficient state associated with uremia. A central role in the host defense against bacterial infections is played by phagocytic polymorphonuclear white blood cells, which are characterized by the capacity to ingest and subsequently destroy bacteria. Disorders in polymorphonuclear cell function are exacerbated by the dialysis procedure and numerous factors including uremic toxins, iron overload, anemia of renal disease, and dialyzer bioincompatibility. It is concluded that the phagocytic defect observed in ESRD is multifactorial, and each factor should be managed individually with specific therapeutic approaches.

Comparison of Infectious Complications between Incident Hemodialysis and Peritoneal Dialysis Patients

The impact of dialysis modality on infection, especially early in the course of dialysis, has not been well studied. This study compared infection between hemodialysis (HD) and peritoneal dialysis (PD) from the start of dialysis and evaluated factors that have an impact on infection risk. In this observational cohort study, all incident dialysis patients (n = 181; HD 119 and PD 62) at a single center from 1999 to 2005 had data collected prospectively beginning day 1 of dialysis. Excluded were those with any previous ESRD therapy. Infection rates were evaluated using multivariate Poisson regression. Overall infection rates were similar (HD 0.77 versus PD 0.86/yr; P = 0.24). Only HD patients had bacteremia (0.16/yr), and only PD patients had peritonitis (0.24/yr). Bacteremia that occurred < or =90 d after start of HD was 0.44/yr, increased compared with overall rate of 0.16/yr (P < 0.004). HD catheters, used in 67% of patients who started HD, were associated with a strikingly increased rate of bacteremia. Peritonitis < or =90 d was 0.22/yr, no different from the overall rate. Modality was not an independent predictor of overall infections (PD versus HD: relative risk 1.30; 95% confidence interval 0.93 to 1.8; P = 0.12) using multivariate analysis. PD and HD patients had similar infection rates overall, but type of infection and risk over time varied. HD patients had an especially high risk for bacteremia in the first 90 d, whereas the risk for peritonitis for the PD cohort was not different over time. These results support the placement of permanent accesses (fistula or PD catheter) before the start of dialysis to avoid use of HD catheters.

An Interventional Controlled Trial Comparing 2 Management Models for the Treatment of Tunneled Cuffed Catheter Bacteremia: A Collaborative Team Model Versus Usual Physician-Managed Care

BACKGROUND

The management of tunneled cuffed catheter (TCC)-associated bacteremias varies among nephrologists. To determine whether patient outcomes after TCC-associated bacteremia can be improved by modifying the management model, we performed an interventional controlled trial comparing a collaborative team model, intervention (INT), with the usual physician-managed model, usual care (UC).

METHODS

INT consisted of an infection manager who worked closely with nephrologists and dialysis staff and made treatment recommendations using the available published guidelines at the time of the study's conception (Dialysis Outcomes Quality Initiative guideline no. 26, 1997) and additional literature-based recommendations. Nephrologists made the final treatment decisions. TCC-associated bacteremia was physician managed in the UC group.

RESULTS

Two hundred twenty-three episodes of TCC-associated bacteremia occurred in 7 outpatient hemodialysis units during the 2-year study period. The INT was associated with a significantly lower incidence of recurrent bacteremia with the same organism (INT, 6% versus UC, 18%; odds ratio, 0.28; 95% confidence interval, 0.09 to 0.8; P = 0.015) and death from sepsis (INT, 0% versus UC, 6%; P < 0.02). In INT units, there was a 45% decrease in the practice of TCC salvage (TCC not removed; P = 0.05). Antibiotic prescribing practices (final antibiotic selection, dose, and duration of therapy) were improved in INT units compared with UC units. By using multivariate analysis, the INT was associated with a 73% decrease in the combined outcome of recurrent bacteremia or septic death (P < 0.02).

CONCLUSION

Implementation of a collaborative team model for the management of TCC-associated bacteremic episodes is associated with improvement in the quality of heath care delivery and patient outcomes.

Comparison of Low-Dose Gentamicin With Minocycline as Catheter Lock Solutions in the Prevention of Catheter-Related Bacteremia

BACKGROUND

Catheter-restricted antibiotic lock solutions were found to be effective in the prevention of catheter-related bacteremia (CRB), but insufficient data are available about the ideal agent and dose. We hypothesized that a low concentration of gentamicin would be as effective as the high doses studied in the past.

METHODS

In this prospective, open-labeled, randomized, clinical trial of patients on long-term hemodialysis therapy, patients were randomly assigned to administration of an antibiotic lock solution of gentamicin/citrate (4 mg/mL), minocycline/EDTA, or the control solution of heparin. Patients were followed up until the study end point of CRB was reached or a censoring event occurred. Interim data analysis was performed after 6 months to assess data safety; efficacy was noted and the study was terminated early.

RESULTS

Sixty-two patients were enrolled into the study, evenly distributed in 3 arms, with data from 1 patient excluded from analysis. Seven of 20 patients in the heparin group (4.0 events/1,000 catheter days), 1 of 21 patients in the minocycline group (0.4 events/1,000 catheter days), and none of 20 patients in the gentamicin group developed bacteremia. Results were statistically significant by using 2-tailed Fisher exact test; heparin versus gentamicin, P = 0.008, and heparin versus minocycline, P = 0.020.

CONCLUSION

Antibiotic lock solutions are superior to the standard heparin lock alone in the prevention of CRBs, and low-dose gentamicin solution has efficacy similar to that of greater concentrations used in previous studies.

Catheter use is high even among hemodialysis patients with a fistula or graft

At any given time, approximately 27% of patients in the United States (US) receive hemodialysis through a permanent catheter. However, this cross-sectional estimate may significantly underestimate the lifetime exposure of patients to hemodialysis catheters, and hence, to the excess risk of the adverse clinical events associated with catheter use. To further clarify catheter use in hemodialysis patients, we identified a cohort of fistula and graft patients in the US Renal Data System using Current Procedural Terminology (CPT) codes. Patients were included if their first hemodialysis was between 1 January 1996 and 31 December 2001, and Medicare was their primary payer. We identified permanent catheter insertions in these patients using CPT codes starting 6 months before their first hemodialysis session (or fistula or graft placement, if earlier), and ending 40 months afterward. Most patients (82%) were >65 years old, 57% were male, and 72% were white. The overall rate of permanent catheter insertions was 44 per 100 patient years, with 57% of patients having at least one catheter insertion. The percent of patients receiving a catheter was similar before (30%) and after (27%) the first fistula or graft placement. Cross-sectional analysis may significantly underestimate the lifetime risk of exposure to hemodialysis catheters. Because catheter use is common even in fistula and graft patients, measures used to prevent adverse events associated with catheter use are important in all patients regardless of current access type.

Predictors and outcome of catheter-related bacteremia in children on chronic hemodialysis

Tunneled central venous catheters are often used in children on chronic hemodialysis. This study was done to evaluate the spectrum of catheter-related bacteremia (CRB) and to determine predictors of recurrent CRB in children on hemodialysis. Chart review was performed in 59 children from a pediatric dialysis unit with chronic, tunneled, cuffed hemodialysis catheters between January 1999 and December 2003. CRB was diagnosed in 48 of 59 (81%) patients. The incidence of CRB was 4.8/1,000 catheter days. Overall catheter survival (290+/-216 days) was significantly longer than infection-free catheter survival (210+/-167 days, p<0.05). Organisms isolated were gram-positive in 67%, gram-negative in 14%, and polymicrobial in 19%. Systemic antibiotics cleared CRB in 34% and an additional 23% cleared with the inclusion of antibiotic-heparin locks; 43% required catheter exchange. There was a significant likelihood of early catheter exchange with polymicrobial CRB (p<0.01). Catheter loss occurred from infection in 63%. Risk factors for CRB included young age (<10 years) and presence of human immunodeficiency virus (HIV) infection. Patients with >2 initial positive blood cultures (p<0.0001) had a significantly higher rate of recurrence after 6 weeks of initial treatment. In conclusion, CRB remains a major determinant of catheter loss. However, overall catheter survival is longer than infection-free catheter survival, suggesting that systemic antibiotics with antibiotic-heparin locks should be the initial step in the management of CRB and this approach may salvage some catheters.

Association of clinic vascular access monitoring practices with clinical outcomes in hemodialysis patients

BACKGROUND

Early identification of access dysfunctions may be associated with improved patient outcomes. We examined whether patient outcomes were associated with vascular access monitoring practices in an incident dialysis cohort.

METHODS

We conducted a national prospective cohort study and analyzed 363 hemodialysis patients who had a first permanent vascular access (arteriovenous fistula or graft) by 6 months after the start of dialysis. Multivariate methods were used to examine associations between monitoring practices and 6-month Kt/V (reaching Kt/V >/=1.2), access intervention, access failure, and 2-year septicemia and all-cause hospitalization and mortality.

RESULTS

Patients who received monitoring weekly or more often (49%) were more likely to have an access intervention (adjusted RH = 1.40, 95% CI, 1.07-1.84) than those who received monitoring less frequently. Additionally, patients treated at clinics that reported performing regular access monitoring (80% of patients) were less likely to be hospitalized for septicemia (IRR = 0.35, 95% CI, 0.21-0.61) or for any cause (IRR = 0.77, 95% CI, 0.60-0.99). There were no statistically significant differences between patients exposed to different vascular access monitoring practices in access failure, achievement of Kt/V, or survival.

CONCLUSION

Frequent monitoring of dialysis access may initially increase the number of interventions but is beneficial to longer-term outcomes, including septicemia-related and all-cause hospitalization.

In Preparation for a Treatment Guideline for Suitable Vascular Access Repair in Japan

In cases of vascular access (VA) for hemodialysis including arteriovenous fistula and arteriovenous graft, venipuncture and hemostasis are usually repeated three times a week. Accordingly, it is assumed that VA vascular disorders are worsened following long-term hemodialysis. In particular, angiostenosis frequently occurs and results in insufficient blood flow or increased venous pressure. Additionally, stenosis is a major cause of VA occlusion. While VA intervention treatment is mainstream for VA stenosis, its major advantage lies in its less invasiveness because it is a percutaneous treatment. A further advantage of this treatment procedure is that the existing VA can be preserved intact. For practical use of VA intervention treatment, however, compliance with the therapeutic indication guideline is required. In K/DOQI of the United States, such a guideline has already been formulated based on evidence and specialist opinion, while the guideline of the European Vascular Access Society is presented in the form of a flowchart. The Japanese Society for Dialysis Therapy is currently preparing a guideline for the construction and maintenance of VA, which introduces the timing and principles of repair of VA in the following six categories: (i) stenosis; (ii) occlusion; (iii) venous hypertension; (iv) steal syndrome; (v) excess blood flow; and (vi) infection. Except for infection, most of the treatments for these events involve VA intervention, thus the need for the guideline for VA intervention treatment is becoming widely recognized.

Clinical Course Associated with Vascular Access Type in a National Cohort of Adolescents Who Receive Hemodialysis: Findings from the Clinical Performance Measures and US Renal Data System Projects

Limited research has described clinical outcomes that are associated with the type of vascular access in pediatric patients who receive maintenance hemodialysis. This retrospective cohort study examined prevalent pediatric patients who were aged 12 to <18 yr and identified in the 2000 ESRD Clinical Performance Measures Project as receiving in-center hemodialysis. Vascular access type as of December 31, 1999, was identified. These patients were linked with 1 yr of data (January 1, 2000, through December 31, 2000) from US Renal Data System standard analytic files that allow for the comparison of rates of hospitalizations and access complications by access type. Of the 418 patients who met inclusion criteria, the mean age was 15.6 yr, 53% were male, 49% were white, the mean time on dialysis was 22 mo, and 42% had a structural/urologic cause of ESRD; 42% of patients had an arteriovenous graft or fistula, and 58% had a vascular catheter. Patients with a vascular catheter as compared with those with a graft or fistula had the following adjusted relative risks (95% confidence interval): 1.84 (1.38 to 2.44) for hospitalization for any cause, 4.74 (2.02 to 11.14) for hospitalization as a result of infection, and 2.72 (2.00 to 3.69) for a complication of vascular access. Vascular catheters are the predominant access type in adolescent patients who receive maintenance hemodialysis and are associated with significantly more hospitalizations and complications.

Infectious complications in chronic kidney disease

Infectious complications in individuals with chronic kidney disease (CKD) pose a significant source of morbidity and mortality. The overall scope of major infectious complications has, however, received little attention even though some of these events may be preventable. We reviewed infectious hospitalization rates in the CKD and end-stage renal disease (ESRD) populations, comparing them with the non-CKD and non-ESRD groups. We also reviewed preventive vaccination rates for influenza, pneumonia, and pneumococcal pneumonia to assess areas of potential improvement. We reviewed the medical literature and present findings based on hospitalization rates for pneumonia, sepsis/bacteremia, and urinary tract infections in the Medicare CKD, ESRD, and non-CKD populations. Vaccination rates were determined from submitted claims for services with specific codes for the vaccinations. Regardless of the primary cause for the development of CKD, primary kidney disease or secondary to hypertension, diabetes mellitus, or other chronic condition, patient outcomes after the development of infections were 3 to 4 times worse than in the non-CKD population. Influenza vaccination rates were 52%, far less than the target of 90%. Pneumococcal pneumonia vaccination rate was only 13.5%, far less than recommended. CKD is associated with significant major infectious complications, which occur at rates 3 to 4 times the general population. Providers can improve prevention by using fewer dialysis catheters and increasing vaccination rates for influenza and pneumococcal pneumonia.

Avoiding trouble down the line: the management and prevention of hemodialysis catheter-related infections

Over the last 2 decades, hemodialysis catheter use has increased. Annually, approximately 30% of patients using a central venous catheter (CVC) experience a septic or bacteremic episode and are subsequently at risk of its associated long-term complications and mortality. Because of the serious clinical and financial impact of hemodialysis catheter-related bacteremias (HCRIs), standardized, validated definitions based on the hemodialysis patient population are necessary in order to better diagnose, monitor, and report HCRI for patient quality assurance and research purposes. The pathophysiology of HCRI involves a complex interaction between a triad that consists of the host patient, the infecting microorganism, and the vehicle catheter. Although the microorganism contribution in the pathogenesis of HCRI is likely most important, certain patient and catheter-related characteristics may be more amenable to manipulation. The key to managing HCRI is on prophylaxis against the initial microorganism catheter adherence and subsequent biofilm development. General and specific prophylactic maneuvers directed at both an intravascular and extraluminal route of microorganism entry are discussed including antibiotic- and silver-impregnated catheters and dressings, subcutaneous access devices, and topical prophylaxis at the exit site. In addition to systemic antibiotic use, the 3 methods of HRCI treatment using catheter salvage, guidewire exchange, and concurrent antibiotic lock are compared. The outcome and complications of HCRI may be serious and highlight the importance of careful, continual infection surveillance. Although the use of a multidisciplinary hemodialysis infection control team is desirable, staffing education and physician feedback have been shown to improve adherence to infection control guidelines and reduce HCRI.

Mortality differences among organisms causing septicemia in hemodialysis patients

Septicemia is a serious problem in hemodialysis patients because it can lead to life-threatening complications and a persistently elevated risk of death. Most analyses have not examined whether there are differences in mortality risk among the organisms that cause these episodes of septicemia. This study was a retrospective cohort analysis of first septicemia hospitalizations during the first year of hemodialysis. Time to death (both in-hospital and within 12 weeks post-discharge) was compared among the different septicemia-causing organisms based on discharge diagnoses in Medicare billing data from 1996 to 2001. The effect of various complications on mortality risk was also evaluated. There were 22,130 septicemia hospitalizations identified. The most common organism identified was Staphylococcus aureus (27%), with no other organism having an incidence >10%. The overall unadjusted death rate from admission through 12 weeks of follow-up was 34%. During the first hospitalization, the death rate was 14%, and during the 12-week period after the hospitalization it was 20%. In adjusted analyses, S. aureus was associated with a 20% higher risk of death both during the in-hospital period and the 12-week post-discharge period, when compared with all other specified organisms. Hospitalizations complicated by meningitis, stroke, or endocarditis were also associated with increased risk of mortality, independent of the organism causing septicemia. Septicemia hospitalizations are associated with a high mortality rate--both during the initial hospitalization and after discharge. Meningitis, stroke, and endocarditis represent particularly serious complications. Overall, septicemia hospitalizations (especially for S. aureus) are serious events, and patients would benefit from better treatment and prevention.

Mortality risk factors in chronic haemodialysis patients with infective endocarditis

BACKGROUND

It is well documented that infective endocarditis (IE) is strongly associated with morbidity and mortality in haemodialysis (HD) patients. Less clear are the mortality risk factors for IE, particularly in an urban African-American dialysis population.

METHODS

IE patients were identified from the medical records for the period from January 1999 to February 2004 and confirmed by Duke criteria. The patients were classified as 'survivors' and 'non-survivors' depending on in-hospital mortality, and risk factors for IE mortality were determined by comparing the two cohorts. Survivors were followed as out-patients with death as the endpoint.

RESULTS

A total of 52 patients with 54 episodes of IE were identified. A catheter was the HD access in 40 patients (74%). Mitral valve (50%) was the commonest valve involved, and Gram-positive infections accounted for 87% of IE. In-hospital mortality was high (37%) and valve replacement was required for 13 IE episodes (24%). On logistic regression analyses, mitral valve disease [P = 0.002; odds ratio (OR) = 15.04; 95% confidence interval (CI) = 2.70-83.61] and septic embolism (P = 0.0099; OR = 9.56; 95% CI = 1.72-53.21) were significantly associated with in-hospital mortality. Using the Cox proportional hazards model, mitral valve involvement (P = 0.0008; hazard ratio 4.05; 95% CI = 1.78-9.21) and IE related to drug-resistant organisms such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus sp. (P = 0.016; hazard ratio 2.43; 95% CI = 1.18-5.00) were associated with poor outcome after hospital discharge.

CONCLUSIONS

IE was associated with high mortality in our predominantly African-American dialysis population, when the mitral valve was involved, or septic emboli occurred and if MRSA or VRE were the causal organisms.

Risk factors for the infections caused by temporary double-lumen hemodialysis catheters

BACKGROUND

Temporary hemodialysis catheters are important devices used in dialysis practice but may be the source of infection in hemodialysis patients.

METHODS

We investigated the infectious complications in 70 hemodialysis patients using 113 hemodialysis catheters.

RESULTS

The frequency of catheter-related bacteremia was 23.9%, of which Staphylococci were the most frequently growing organism (96.3%). Exit-site infection was observed in one patient. No cases were lost due to the infectious complications. The risk for the development of catheter-related bacteremia was increased after the 24th day of catheterization and after the second venous puncture.

CONCLUSIONS

There was a positive correlation between hypoalbuminemia and bacteremia. Internal jugular venous catheterization and hypoalbuminemia were determined as risk factors for the development of catheter-related bacteremia. The risk factors for catheter-related bacteremia in patients with hemodialysis catheter should be determined and modified in order to decrease infectious complications.

Septicemia in Patients with ESRD Is Associated with Decreased Hematocrit and Increased Use of Erythropoietin

Septicemia, a common complication in chronic dialysis patients, may be an important factor in erythropoietin (EPO) hyporesponsiveness, because it is a form of inflammation. The quantitative impact of septicemia on EPO requirements has not been studied. The purpose of this study was to analyze patterns of EPO use and levels of anemia among patients who had ESRD and were hospitalized with septicemia. Using United States Renal Data System data, septicemia admissions were identified in patients with first ESRD service from 1996 to 2001. Mean EPO dosage and hematocrit (Hct) level were analyzed from 2 mo before until 3 mo after admission and compared with patients who were hospitalized with acute myocardial infarction (AMI) and patients with no hospitalizations. A total of 4640 hospitalized patients were included in the analysis: 3975 for septicemia and 665 for AMI. In both groups, mean Hct declined significantly in the month of admission and increased in the second month after admission. At all time points, both groups had significantly lower Hct levels compared with the nonhospitalized group. Mean EPO dosage increased, most rapidly in the month after admission. EPO use was highest in the septicemia group. Hospitalization with septicemia is associated with worsening anemia and increasing EPO use. This also was observed for patients who were hospitalized with AMI, suggesting that acute intercurrent illness plays an important role in EPO hyporesponsiveness. Strategies to prevent septicemia are important not only to decrease clinical morbidity but also to conserve EPO usage and thus contain the costs of care for this complex patient population.