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Background and Objectives: Although most patients receiving maintenance dialysis exhibit initial seroresponse to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, concerns exist regarding the durability of this antibody response. This study evaluated seroresponse over time., Design, Setting, Participants, & Measurements: This retrospective cohort study included patients on maintenance dialysis, from a midsize national dialysis provider, who received a complete SARS-CoV-2 vaccine series and had at least one antibody titer checked after full vaccination. IgG spike antibodies (anti-spike IgG) titers were assessed monthly with routine laboratory tests after vaccination; the semiquantitative assay reported a range between zero and ≥20 Index. Descriptive analyses compared trends over time by history of coronavirus disease 2019 (COVID-19) and vaccine type. Time-to-event analyses examined the outcome of loss of seroresponse (anti-spike IgG <1 Index or development of COVID-19). Cox regression adjusted for additional clinical characteristics., Results: Among 1870 patients receiving maintenance dialysis, 1569 had no prior COVID-19. Patients without prior COVID-19 had declining titers over time. Among 443 recipients of BNT162b2 (Pfizer), median (interquartile range) anti-spike IgG titer declined from ≥20 (5.89 to ≥20) in month 1 after full vaccination to 1.96 (0.60-5.88) by month 6. Among 778 recipients of mRNA-1273 (Moderna), anti-spike IgG titer declined from ≥20 (interquartile range, ≥20 to ≥20) in month 1 to 7.99 (2.61 to ≥20) by month 6. The 348 recipients of Ad26.COV2.S (Janssen) had a lower titer response than recipients of an mRNA vaccine over all time periods. In time-to-event analyses, recipients of Ad26.COV2.S and mRNA-1273 had the shortest and longest time to loss of seroresponse, respectively. The maximum titer reached in the first 2 months after full vaccination was associated with durability of the anti-spike IgG seroresponse; patients with anti-spike IgG titer 1-19.99 had a shorter time to loss of seroresponse compared with patients with anti-spike IgG titer ≥20 (hazard ratio, 15.5; 95% confidence interval, 11.7 to 20.7)., Conclusions: Among patients receiving maintenance dialysis, vaccine-induced seroresponse wanes over time across vaccine types. Early titers after full vaccination are associated with the durability of seroresponse., (Copyright © 2022 by the American Society of Nephrology.)

End-stage kidney disease patients who are candidates for surgical arteriovenous fistula creation commonly experience obstacles to a functional surgical arteriovenous fistula, including protracted wait time for creation, poor maturation, and surgical arteriovenous fistula dysfunction that can result in significant patient morbidity. The recent approval of two endovascular devices designed to create a percutaneous arteriovenous fistula enables arteriovenous fistula creation to be placed in the hands of interventionalists, thereby increasing the number of arteriovenous fistula providers, reducing wait times, and allowing the patient to avoid surgery. Moreover, current studies demonstrate that patients with percutaneous arteriovenous fistula experience improved time to arteriovenous fistula maturation. Yet, in order to realize the potential advantages of percutaneous arteriovenous fistula creation within our hemodialysis patient population, it is critical to select appropriate patients, ensure adequate patient and dialysis unit education, and provide sufficient instruction in percutaneous arteriovenous fistula cannulation and monitoring. In this White Paper by the American Society of Diagnostic and Interventional Nephrology, experts in interventional nephrology, surgery, and interventional radiology convened and provide recommendations on the aforementioned elements that are fundamental to a functional percutaneous arteriovenous fistula.

The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) has provided evidence-based guidelines for hemodialysis vascular access since 1996. Since the last update in 2006, there has been a great accumulation of new evidence and sophistication in the guidelines process. The 2019 update to the KDOQI Clinical Practice Guideline for Vascular Access is a comprehensive document intended to assist multidisciplinary practitioners care for chronic kidney disease patients and their vascular access. New topics include the end-stage kidney disease "Life-Plan" and related concepts, guidance on vascular access choice, new targets for arteriovenous access (fistulas and grafts) and central venous catheters, management of specific complications, and renewed approaches to some older topics. Appraisal of the quality of the evidence was independently conducted by using a Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, and interpretation and application followed the GRADE Evidence to Decision frameworks. As applicable, each guideline statement is accompanied by rationale/background information, a detailed justification, monitoring and evaluation guidance, implementation considerations, special discussions, and recommendations for future research., (Copyright © 2019. Published by Elsevier Inc.)

Bloodstream infections are an important cause of hospitalizations, morbidity, and mortality in patients receiving hemodialysis. Eliminating bloodstream infections in the hemodialysis setting has been the focus of the Centers for Disease Control and Prevention (CDC) Making Dialysis Safer for Patients Coalition and, more recently, the CDC's partnership with the American Society of Nephrology's Nephrologists Transforming Dialysis Safety Initiative. The majority of vascular access-associated bloodstream infections occur in patients dialyzing with central vein catheters. The CDC's core interventions for bloodstream infection prevention are the gold standard for catheter care in the hemodialysis setting and have been proven to be effective in reducing catheter-associated bloodstream infection. However, in the United States hemodialysis catheter-associated bloodstream infections continue to occur at unacceptable rates, possibly because of lapses in adherence to strict aseptic technique, or additional factors not addressed by the CDC's core interventions. There is a clear need for novel prophylactic therapies. This review highlights the recent advances and includes a discussion about the potential limitations and adverse effects associated with each option., (Copyright © 2020 by the American Society of Nephrology.)

The maintenance of vascular access patency for end-stage renal disease patients on hemodialysis is necessary for survival. Many nephrologists, nurse practitioners, and nurses have limited experience with the physical examination of the arteriovenous fistula. In this review, we define key terms used in the assessment of an arteriovenous fistula. We discuss the arteriovenous fistula physical exam, including details of inspection, palpation, and auscultation. Using these concepts, we review the abnormal findings that can assist practitioners in determining the location of a stenosis. We review the existing literature that validates physical exam findings with gold standard tests such as ultrasound and angiography. Finally, we review data supporting the value of training physicians and nurses in arteriovenous fistula physical examination.

Stents are ubiquitously utilized in coronary and peripheral arterial disease. Interventional nephrologists, however, place stents in the venous outflow of the arteriovenous access. Stenosis is the predominant pathology that causes access dysfunction and will ultimately lead to thrombosis if uncorrected. Angioplasty and stent deployment are the current techniques available to combat stenosis. From initial bare metal stainless steel stents, the current generations of stents used are predominately covered nitinol stents. The latest randomized control trials reveal that stents decrease the number of interventions required to maintain patency but do not improve the overall access survival. Furthermore, bare metal stents have been shown to be inferior to stent grafts. This review discusses indications for stent deployment in the hemodialysis access, the current evidence for their use, and briefly touches on their complications.

The arteriovenous fistula is currently the best permanent access for the hemodialysis patient. Unfortunately, stenosis impairs maturation, long-term survival, and function of the arteriovenous fistula. Angioplasty currently is the best procedure for the treatment of immature and dysfunctional arteriovenous fistulas. In this review, the authors discuss the optimum time to evaluate arteriovenous fistulas for maturity, methods of evaluation for maturity, and the role of angioplasty in salvaging immature arteriovenous fistulas. The review also discusses the effect of stenosis on dysfunction in mature arteriovenous fistulas and the role of angioplasty to treat this complication. Finally, the impact of cutting balloons and drug-eluting balloons in the treatment of resistant and recurrent stenosis, respectively, is also discussed.

Stent strut protrusion through the skin is a rare and a potentially dangerous complication from the cannulation of stents placed within arterio-venous fistulas and grafts. Such cases are usually managed surgically. We present a case wherein strut penetration of an arterio-venous fistula was noted at the distal (uncovered) end of a Fluency Plus(®) tracheo bronchial stent graft. After analyzing the various reasons why this may have happened, a nonsurgical approach was taken to preserve the access and manage strut protrusion., (© 2014 Wiley Periodicals, Inc.)

During hemodialysis, the development of hypotension or symptoms suggestive of ischemia is used as a surrogate marker for the establishment of dry weight. These symptoms manifest commonly as muscle cramps, chest pain or abdominal pain. Hemodialysis patients are also prone to vascular calcification which may be medial or intimal. We report the case of a 68-year-old male who developed testicular pain while attempting to establish dry weight. Computerized tomography scan of his abdomen showed extensive vascular calcification. The end result in this case was bilateral orchiectomy. Histopathology revealed hyperplastic arteriolosclerosis with intimal calcification contributing to ischemia., (© 2012 The Authors. Hemodialysis International © 2012 International Society for Hemodialysis.)

Use of long-term dialysis catheters (e.g., tunneled dialysis catheters) predisposes patients to complications. While catheter-related bacteremia is one of the commonest encountered complication, there are a series of rare complications, namely catheter adherence to the vessel wall, catheter fracture, and vessel perforation, that can occur. This article attempts to discuss such complications with emphasis on potential risk factors, clinical presentations, and management options.

Visionary nephrologists in the early 1960s invented the dialysis machine, constructed arteriovenous shunts and fistulas, and designed vascular and peritoneal catheters to provide their patients with long-term dialysis. As the number of dialysis patients grew, the construction and care of vascular access was abandoned by nephrologists to surgeons and radiologists. There was a decline in the number of fistulas and an increase in grafts in the United States. Vascular access was not the first priority for the nonnephrologists, and this set the stage for the emergence of diagnostic and interventional nephrologists. These self-taught nephrologists trained others, resulting in a critical mass of subspecialists who founded the Society of Diagnostic and Interventional Nephrology. This review traces the origin of this exciting field from its pioneers to the society as it exists today. The future of this society depends on academic nephrology fellowship programs fostering training and research in this field.

Background: During clinical application of flow surveillance of hemodialysis grafts, the risk of thrombosis is assessed month after month, rather than after one or several measurements, as has been done in published studies. Adequate assessment of risk should consider the many measurements obtained over time., Study Design: Prospective cohort diagnostic test study., Setting & Participants: 176 patients with hemodialysis grafts from 2 university-affiliated dialysis units during a 6-year period., Index Tests: Monthly measurement of graft blood flow or change in flow., Outcome: Graft thrombosis., Results: We used logistic regression analysis to compute the risk of thrombosis and used receiver operating characteristic (ROC) curves to assess the accuracy in predicting thrombosis within 1 month. Newer grafts were most likely to thrombose, whereas older grafts were unlikely to thrombose even at low flows or large decreases in flow. Areas under the ROC curves were 0.698 for flow and 0.713 for change in flow measured over 2 months. Flow predicted thrombosis with a sensitivity of 53% at a specificity of 79%, and change in flow had a sensitivity of 58% at a specificity of 75%. More than half the thromboses lacked a change in flow measurement, usually because thrombosis occurred before a change could be measured. Thus, the effective predictive accuracy of change in flow was much less than the ROC curves indicated because the curves do not consider missing measurements., Limitations: Performance characteristics of index tests may vary across patient populations., Conclusion: Flow and change in flow are inaccurate predictors of thrombosis. Many thromboses are not predicted, and intervention based on surveillance likely yields many unnecessary procedures. Thus, this study does not support routine application of surveillance to prevent thrombosis.

Nephrologists have to place temporary dialysis catheters for hemodialysis in emergency situations. Since there is a dearth of literature on this subject, the authors have written guidelines for the safe and successful placement of these catheters. These instructions should be of help to nephrology trainees who want to master the art of central venous line placement. Based on their experience, the authors have provided a number of tips and techniques for temporary catheter placement in the femoral, internal jugular, and subclavian veins, with and without ultrasound guidance. Patient positioning, preparation of the catheter insertion tray, handling of ultrasound probe, cannulation of the central veins, and guide wire and dilator insertion are described in detail. These guidelines should assist the novice in placing temporary catheters with ease and with minimal complications.

Background: Progressive venous stenosis mediated, in part, by inflammatory cytokines is a major cause of synthetic hemodialysis graft failure. A tumor necrosis factor-alpha (TNF-alpha) gene polymorphism (G to A, position -308) has been shown to increase plasma cytokine levels and severity of diseases with an underlying inflammatory component., Methods: We genotyped 67 patients with synthetic polytetrafluoroethylene (PTFE) grafts and examined the association of the high-(AA or GA) and low- (GG) production TNF-alpha-08 genotypes with the rate of graft failures/thrombosis and graft survival., Results: Hemodialysis patients with the high-production TNF-alpha genotypes had a significantly increased rate of PTFE graft failure at 90 days (37.2% versus 14%) and 1 year (62.8% versus 34.4%) after graft placement compared with patients with the low-production genotype (respectively). Hemodialysis patients with the high-production TNF-alpha genotypes had significantly lower cumulative PTFE graft survival at 1 year (29.4% +/- 11.1% versus 71.2 +/- 6.8%) and 2 years (22.1% +/- 10.5% versus 48.2 +/- 8.1%) compared with patients with the low-production genotype (respectively). Patients with the A allele had approximately twice the mean thrombosis rate compared with those who had the low-production TNF-alpha genotype (3.3 +/- 0.8 versus 1.7 +/- 0.4 thromboses/patient/year, respectively; mean +/- SEM, p < .05)., Conclusions: These data suggest that the TNF-alpha -308 A allele is associated with increased PTFE graft thrombosis and failure in hemodialysis patients.

Background: The incidence of Mycobacterium tuberculosis in hemodialysis (HD) and renal transplant (RT) patients in developing countries is high. With the resurgence of tuberculosis in the US, insights gained in the diagnosis and treatment of this infection in HD and RT patients in developing countries should be valuable to physicians in the West., Methods: A retrospective study of 40 cases of tuberculosis, 24 in HD patients (24/177, 13.6%) and 16 in RT patients (16/109, 14.7%) diagnosed over a period of 21 months in one center., Results: The clinical features, diagnostic procedures, and management dilemmas of this group of patients are described in this report. Diabetes mellitus was the most common associated disease in both groups of patients. Fever, the most common presenting sign, was persistent low grade in 66.6% of HD patients and high intermittent in 56.2% of RT patients. Fever of unknown origin was only seen in RT patients. Pulmonary involvement was most common in both groups, presenting either as infiltrates or effusions. Tuberculous peritonitis was seen only in HD patients (33.3%). Eight HD patients were treated for tuberculosis for variable periods prior to transplantation, 4 of whom had less than 6 months of therapy. None had a recurrence of tuberculosis after transplantation. Because of the known cyclosporin-lowering effect of rifampicin resulting in an increased cost of immunosuppressive therapy, 13 patients were treated successfully with rifampicin-sparing therapy., Conclusion: Tuberculosis should be included in the differential diagnosis of fever in HD and RT patients, especially if fever is of unknown origin in the RT patient. M. tuberculosis in the renal transplant patient can present with high intermittent fever. Partial treatment of tuberculosis is sufficient prior to renal transplantation but treatment should be continued to completion after transplantation. If the cost of immunosuppressive therapy is prohibitive because of rifampicin, rifampicin-sparing antituberculosis therapy can be successfully employed in RT patients., (Copyright 2000 S. Karger AG, Basel)

This study examines whether there is a relationship between aluminum overload and the accumulation of lipofuscin products (aging pigments) and lipid peroxides in red blood cells (RBC) of hemodialyzed patients. Lipid peroxides levels were assessed by the thiobarbituric acid reactivity; lipofuscin products were assessed by determining fluorescence in the lipid extracts at excitation 360 nm and emission 440 nm. Aluminum was measured by atomic absorption spectrophotometry. Controls were age-matched normal volunteers. Data show that there was a significant increase in the lipid peroxides and lipofuscin products in hemodialyzed patients compared with controls even after normalization with hemoglobin or phospholipids in RBC. Further, the increase in the lipid peroxides and lipofuscin products significantly correlated with the levels of aluminum accumulation in RBC of hemodialyzed patients. This study suggests that aluminum overload has a role in increased membrane peroxidation, which in turn can cause reduced RBC life span and contribute to anemia in chronic renal failure patients.

To identify factors that may explain the persistently high mortality of acute renal failure (ARF), we compared the cause, clinical course, and outcome of 55 consecutive patients with ARF who underwent hemodialysis (HD) from 1962 to 1969 with 46 similar patients from 1979 to 1981 at the same medical center. We noted an overall increase in mortality from 54.5% to 71.7%. There was an increase in the number of elderly patients developing ARF, but age per se did not influence survival. There was a significant increase in mortality in younger patients resulting from the severity of their underlying illness. We saw an increase in the number of complicating factors occurring at the onset of ARF that correlated with the increase in mortality. In survivors ARF was more prolonged in our most recent experience. The development of prolonged, complicated ARF and the poor survival seen in younger patients led to the increase in mortality in our patients.

A higher prevalence of aluminum-associated microcytic anemia was noted in hemodialysis unit A (n = 67) compared to unit B (n = 39). This finding could not be explained by differences in the aluminum content of reverse osmosis (RO) water or intake of antacids containing aluminum by patients in the two units. An intermittent source of aluminum contamination was suspected when water aluminum and total dissolved solutes (TDS) were measured at several sites in the water treatment facility of unit A. A one-way valve that maintained unidirectional flow in an RO bypass circuit was found missing. Intermittent pressure changes in this circuit altered the direction of water flow causing mixing of partially purified water with RO water. Installation of the valve stopped contamination and resulted in a decrease in plasma aluminum concentration from 183 +/- 12 micrograms/L to 76 +/- 7.3 micrograms/L, erythrocyte aluminum concentration from 210 +/- 31 micrograms/L to 61 +/- 9 micrograms/L and microcytosis from 58% to 8% in patients (n = 48) when measured 6 months later. Because contamination was missed in spite of water testing at the RO site, these findings underscore the importance of measuring water aluminum and TDS content at the dialysis stations. Frequent water testing at dialysis stations, familiarity with the design of water treatment facilities, and recognition of aluminum overload can lead to early detection and correction if similar types of aluminum contamination should occur.

A method for measuring erythrocyte aluminum content was developed. Erythrocyte aluminum levels correlated with plasma aluminum concentrations in normal controls and in patients undergoing dialysis (r = 0.90, p less than 0.001). In vitro studies showed that erythrocyte aluminum concentrations were not altered by contamination of blood samples, which is a common problem with plasma determinations. The need for anticoagulation and rapid processing were disadvantages of this assay. In the dialysis population studied, the correlative data between mean cell volume and both plasma and erythrocyte aluminum levels (r = -0.50, p less than 0.001; and r = -0.69, p less than 0.001) and lack of correlation with serum ferritin suggested that aluminum overload and not iron deficiency was the cause of microcytic anemia. Patients undergoing continuous ambulatory peritoneal dialysis had lower plasma and erythrocyte aluminum levels and absence of microcytic anemia compared with patients undergoing hemodialysis. Therapy with deferoxamine in 13 patients with aluminum-related microcytic anemia resulted in a decrease in erythrocyte and plasma aluminum content in all patients (265.5 +/- 69.2 micrograms/L to 22.6 +/- 9.7 micrograms/L and 196 +/- 30 micrograms/L to 129 +/- 13.8 micrograms/L). The relatively smaller decrease in plasma aluminum levels suggested mobilization of aluminum from tissues other than erythrocytes. Aluminum chelation most probably occurred from premature erythrocytes, because in vitro studies showed that deferoxamine was unable to chelate aluminum from mature erythrocytes. Hemoglobin level, hematocrit measurement, and mean cell volume showed significant improvement (p less than 0.001). Ten patients showed normalized mean cell volume after 6.2 +/- 2 months of therapy.(ABSTRACT TRUNCATED AT 250 WORDS)