Radiology reporting of incidental osteoporotic vertebral fragility fractures present on CT studies: results of UK national re-audit

AIM

To describe a UK-wide re-audit of the 2019 Royal College of Radiologists (RCR) audit evaluating patient-related data and organisational infrastructure in the radiological reporting of vertebral fragility fractures (VFFs) on computed tomography (CT) studies and to assess the impact of a series of RCR interventions, initiated to raise VFF awareness, on reporting practice and outcomes.

MATERIALS AND METHODS

Patient specific and organisational questionnaires largely replicated those utilised in 2019. The patient questionnaire involved retrospective analysis of between 50 and 100 consecutive, non-traumatic CT studies which included the thoracolumbar spine. All RCR radiology audit leads were invited to participate. Data collection commenced from 1 April 2022.

RESULTS

Data were supplied by 129/194 (67%) departments. One thousand five hundred and eighty-six of 7,316 patients (21.7%) had a VFF on auditor review. Overall improvements were demonstrated in key initial/provisional reporting results; comment on spine/bone (93.2%, 14.4% improvement, p<0.0002); fracture severity assessment (34.7%, 8.5% improvement, p=0.0007); use of recommended terminology (67.8%, 7.5% improvement, p=0.0034); recommendations for further management (11.7%, 9.1% improvement, p<0.0002).

CONCLUSIONS

The 2022 national re-audit confirms improvements in diagnostic performance and practice in VFF reporting. Continuing work is required to build on this improvement and to further embed best practice.

Serial SARS-CoV-2 Antibody Titers in Vaccinated Dialysis Patients: Prevalence of Unrecognized Infection and Duration of Seroresponse

Rationale & Objective

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections are likely underdiagnosed, but the degree of underdiagnosis among patients receiving maintenance dialysis is unknown. The durability of the immune response after the third vaccine dose in this population also remains uncertain. This descriptive study tracked antibody levels to (1) assess the rate of undiagnosed infections and (2) characterize seroresponse durability after the third dose.

Study Design

Retrospective observational study.

Setting & Participants

SARS-CoV-2-vaccinated patients receiving maintenance dialysis through a national dialysis provider. Immunoglobulin G spike antibodies [anti-spike immunoglobulin (Ig) G] titers were assessed monthly after vaccination.

Exposures

Two and 3 doses of SARS-CoV-2 vaccine.

Outcomes

Undiagnosed and diagnosed SARS-CoV-2 infections; anti-spike IgG titers over time.

Analytical Approach

Undiagnosed SARS-CoV-2 infections were identified as an increase in anti-spike IgG titer of ≥100 BAU/mL, not associated with receipt of vaccine or diagnosed SARS-CoV-2 infection (by polymerase chain reaction test or antigen test). In descriptive analyses, anti-spike IgG titers were followed over time.

Results

Among 2,703 patients without previous coronavirus disease 2019 (COVID-19) who received an initial 2-dose vaccine series, 271 had diagnosed SARS-CoV-2 infections (3.4 per 10,000 patient-days) and 129 had undiagnosed SARS-CoV-2 infections (1.6 per 10,000 patient-days). Among 1,894 patients without previous COVID-19 who received a third vaccine dose, 316 had diagnosed SARS-CoV-2 infections (7.0 per 10,000 patient-days) and 173 had undiagnosed SARS-CoV-2 infections (3.8 per 10,000 patient-days). In both cohorts, anti-spike IgG levels declined over time. Of the initial 2-dose cohort, 66% had a titer of ≥500 BAU/mL in the first month, with 24% maintaining a titer of ≥500 BAU/mL at 6 months. Of the third dose cohort, 95% had a titer of ≥500 BAU/mL in the first month after the third dose, with 77% maintaining a titer of ≥500 BAU/mL at 6 months.

Limitations

The assays used had upper limits.

Conclusions

Among patients receiving maintenance dialysis, about 1 in every 3 SARS-CoV-2 infections was undiagnosed. Given this population's vulnerability to COVID-19, ongoing infection control measures are needed. A 3-dose primary mRNA vaccine series optimizes seroresponse rate and durability.

Plain-Language Summary

Patients receiving maintenance dialysis have been particularly vulnerable to COVID-19. Using serially measured antibodies, we found that a substantial proportion (about one-third) of SARS-CoV-2 infections among this population had been missed, both among those who had completed a 2-dose vaccine series and among those who had received a third vaccine dose. Such missed infections likely had only mild or minimal symptoms, but this failure to recognize all infections is concerning. Furthermore, vaccines have been effective among patients receiving dialysis, but our study additionally shows that the immune response wanes over time, even after a third dose. There is therefore a role for ongoing vigilance against this highly transmissible infection.

Gender Differences in Physician Burnout: Driving Factors and Potential Solutions

Introduction Burnout among physicians has reached an epidemic level, with substantially higher rates among women. In this brief report, the authors evaluate recent literature to identify major factors leading to gender differences in physician burnout. Methods The authors review data on gender within each of the key drivers of burnout, including workload and job demands, efficiency and resources, control and flexibility, organizational culture and values, social support and community at work, work-life integration, and meaning at work. Results Women physicians face a higher workload, spending more time in electronic health records, and more time per patient. Women physicians also receive fewer resources and report less control over their workload and schedules. Organizational culture factors, such as a lack of women in leadership roles, compensation disparities, lower rates of career advancement and academic promotion, as well as gender bias, microaggressions, and harassment, also play a key role in gender disparities in burnout. Disproportionate responsibilities outside of work, including childcare and elder care, contribute to less satisfaction with work-life integration. Additionally, women physicians report lower self-compassion and perceived appreciation. These factors ultimately lead to decreased professional fulfillment and higher burnout rates among women physicians. Finally, the authors present proposals to address each of these factors at an organizational level, to effectively address the high burnout rate among women physicians. Conclusion Burnout among women physicians is substantially higher compared to men and stems from multiple factors. It is crucial for organizations to evaluate the gender differences within each burnout driver and develop sustainable strategies to reduce disparities.

Hyaluronan Inhibition as a Therapeutic Target for Diabetic Kidney Disease: What Is Next?

Diabetic kidney disease (DKD) is the leading cause of CKD and ESKD in the United States and worldwide. Pharmacotherapy and lifestyle modifications for glycemia, dyslipidemia, and BP control have shown success in slowing the progression of DKD. Traditional treatments, such as angiotensin-converting enzyme inhibitors or angiotensin receptor blockers and more recently the use of sodium-glucose cotransporter 2 inhibitors, nonsteroidal selective mineralocorticoid receptor antagonists, such as finerenone, and glucagon-like peptide 1 receptor agonists, have led to added benefits on various outcomes. However, significant residual risk for DKD progression remains despite the current standard-of-care approaches. Arteriolar hyalinosis (AH) is among the key findings seen on kidney biopsies of patients with DKD. It results from the excessive accumulation of hyaluronan (HA) in the arterioles. AH has not been targeted specifically by any of the therapeutic methods currently being used. We discuss in this manuscript the potential use of a selective therapy targeting AH and the increased total renal HA deposits using a HA synthesis inhibitor in DKD.

Serial SARS-CoV-2 antibody titers in vaccinated dialysis patients: prevalence of unrecognized infection and duration of seroresponse

Rationale & Objective

SARS-CoV-2 infections are likely underdiagnosed, but the degree of underdiagnosis among maintenance dialysis patients is unknown. Durability of the immune response after third vaccine doses in this population also remains uncertain. This study tracked antibody levels to 1) assess the rate of undiagnosed infections and 2) characterize seroresponse durability after third doses.

Study Design

Retrospective observational study.

Setting & Participants

SARS-CoV-2 vaccinated patients receiving maintenance dialysis through a national dialysis provider. Immunoglobulin G spike antibodies (anti-spike IgG) titers were assessed monthly following vaccination.

Exposures

Two and three doses of SARS-CoV-2 vaccine.

Outcomes

Undiagnosed and diagnosed SARS-CoV-2 infections; anti-spike IgG titers over time.

Analytical Approach

"Undiagnosed" SARS-CoV-2 infections were identified as an increase in anti-spike IgG titer of ≥ 100 BAU/mL, not associated with receipt of vaccine or "diagnosed" SARS-CoV-2 infection (by PCR or antigen test). In descriptive analyses, anti-spike IgG titers were followed over time.

Results

Among 2660 patients without prior COVID-19 who received an initial two-dose vaccine series, 371 (76%) SARS-CoV-2 infections were diagnosed and 115 (24%) were undiagnosed. Among 1717 patients without prior COVID-19 who received a third vaccine dose, 155 (80%) SARS-CoV-2 infections were diagnosed and 39 (20%) were undiagnosed. In both cohorts, anti-spike IgG levels declined over time. Of the initial two-dose cohort, 66% had a titer ≥ 500 BAU/mL in the first month, with 23% maintaining a titer ≥ 500 BAU/mL at six months. Of the third dose cohort, 95% had a titer ≥ 500 BAU/mL in the first month after the third dose, with 76% maintaining a titer ≥ 500 BAU/mL at six months.

Limitations

Assays used had upper limits.

Conclusions

Among maintenance dialysis patients, 20-24% of SARS-CoV-2 infections were undiagnosed. Given this population's vulnerability to COVID-19, ongoing infection control measures are needed. A three-dose primary mRNA vaccine series optimizes seroresponse rate and durability.

CMS ESRD quality incentive program has not improved patient dialysis vascular access

PURPOSE

Over 468,000 patients in the United States use hemodialysis to manage End Stage Renal Disease (ESRD). The purpose of this study was to determine whether the dialysis access Clinical Performance Measures (CPMs) of Centers for Medicare & Medicaid Services (CMS) ESRD Quality Incentive Program (QIP) have increased arteriovenous fistula (AVF) rates and decreased long-term tunneled hemodialysis catheter (TDC) rates among hemodialysis patients in United States.

METHODS

Retrospective observational study: evaluated reported AVF and long-term TDC rates of 4804 dialysis facilities which reported dialysis access data as part of the ESRD QIP from Payment Year (PY) 2014-2020. Facilities were also sorted by specific additional criteria to examine disparities in dialysis access.

RESULTS

Mean AVF rates of included facilities increased from 63.7% in PY 2014 to 67.2% in PY 2016 (p < 0.05), did not change in PY 2017 (p > 0.05), and declined significantly in PY 2018-2020 to 64.1% in PY 2020, near AVF rates at the inception of program. Long-term TDC rates decreased from 10.4% in PY 2014 to 9.88% in PY 2015 (p < 0.05), then increased in PY 2015-PY 2020 to rates higher than at the inception of program, at 11.8% in PY 2020 (p < 0.05). Facilities serving majority Black ZIP Code Tabulation Areas (ZCTAs) or ZCTAs with median income <$45,000 achieved significantly lower AVF rates (p < 0.05) with no significant difference in long-term TDC rates (p > 0.05). AVF rates correlated positively and long-term TDC rates correlated negatively with star rating of facilities (p < 0.05).

CONCLUSION

As one of the first financial QIPs in healthcare, the ESRD QIP has not achieved the stated goals of the CMS to increase AVF access rates above 68% and reduce long-term TDC clinical rates below 10%. Systemic disparities in race, geographic region, economic status, healthcare access, and education of providers and patients prevent successful attainment of goal metrics.

Seroresponse to SARS-CoV-2 Vaccines among Maintenance Dialysis Patients over 6 Months

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.

Scleroderma Renal Crisis Associated With Microangiopathic Hemolytic Anemia in a Patient With Seronegative Scleroderma and Monoclonal Gammopathy

Systemic sclerosis with negative serology, particularly that complicated by scleroderma renal crisis (SRC), is rarely encountered. We describe a patient with seronegative systemic sclerosis who developed acute kidney injury, proteinuria, and hypertensive emergency following motor vehicle-related trauma and in the setting of nonsteroidal anti-inflammatory drug use. Findings on physical examination, imaging, and skin biopsy led to a clinical diagnosis of scleroderma, despite the lack of supportive laboratory data. IgG lambda paraproteinemia was detected on workup. Bone marrow biopsy showed plasmacytosis and trace lambda-restricted plasma cells consistent with monoclonal gammopathy of undetermined significance. Chemotherapy was initially started given concern for myeloma with cast nephropathy but was later stopped after a kidney biopsy revealed thrombotic microangiopathy (TMA). The SRC associated with TMA was ultimately diagnosed, though atypical hemolytic uremic syndrome (aHUS) induced perhaps by monoclonal gammopathy or hypertension was also possible. Captopril and eculizumab were initiated for SRC and aHUS, respectively. Despite therapy, renal function did not recover, and the patient required hemodialysis indefinitely. This case highlights clinical features common to both SRC and aHUS as well as points out a few ways to differentiate between them.

ASDIN white paper: Management of cephalic arch stenosis endorsed by the American Society of Diagnostic and Interventional Nephrology

Brachiocephalic arteriovenous fistulas (AVF) makeup approximately one third of prevalent dialysis vascular accesses. The most common cause of malfunction with this access is cephalic arch stenosis (CAS). The accepted requirement for treatment of a venous stenosis lesion is ⩾50% stenosis associated with hemodynamically abnormalities. However, the correlation between percentage stenosis and a clinically significant decrease in access blood flow (Qa) is low. The critical parameter is the absolute minimal luminal diameter (MLD) of the lesion. This is the parameter that exerts the key restrictive effect on Qa and results in hemodynamic and functional implications for the access. CAS is the result of low wall shear stress (WSS) resulting from the effects of increased blood flow and the unique anatomical configuration of the CAS. Decrease in WSS has a linear relationship to increased blood flow velocity and neointimal hyperplasia exhibits an inverse relationship with WSS. The result is a stenotic lesion. The presence of downstream venous stenosis causes an inflow-outflow mismatch resulting in increased pressure within the access. Qa in this situation may be decreased, increased, or within a normal range. Over time, the increased intraluminal pressure can result in marked aneurysmal changes within the AVF, difficulties with cannulation and the dialysis treatment, and ultimately, increasing risk of access thrombosis. Complete characterization of the lesion both hemodynamically and anatomically should be the first step in developing a strategy for management. This requires both access flow measurement and angiographic imaging. Patients with CAS present a relatively broad spectrum as relates to both of these parameters. These data should be used to determine whether primary treatment of CAS should be directed toward the anatomical lesion (small MLD and low Qa) or the pathophysiology (large MLD and high Qa).

New Horizons in Dialysis Access: Approach to Hand Ischemia

Hand ischemia is a relatively common complication of hemodialysis arteriovenous (AV) access. Clinical manifestations frequently start with pale and cold ipsilateral hand. Symptoms can progress to pain during dialysis and can eventually lead to tissue necrosis and gangrene if not addressed in a timely fashion. Comprehensive physical examination of the hand, AV access, and comparing it with the contralateral hand will assist in differentiating hand ischemia from carpal tunnel syndrome, osteoarthritis of the hand, and others. There are several treatment options for hand ischemia based on the severity of symptoms. Conservative management with careful monitoring can be applied in early stages. However, if symptoms persist or worsen, a full arteriogram of the ipsilateral extremity should be performed to evaluate for the presence of arterial stenosis. Angioplasty of the arterial stenosis, if present, will frequently lead to the resolution of symptoms. There are several percutaneous and surgical treatment options for hand ischemia, if no arterial stenosis was found or angioplasty does not relieve symptoms. We discuss in this article these treatment options in detail. Treatment goal is to improve hand ischemia symptoms while maintaining hemodialysis AV access and preserving patient's hand. Access ligation remains a treatment of last resort.

Hemodialysis-associated soft tissue amyloidomas of the chest and abdominal wall

Amyloidoma is a highly unusual presentation of amyloidosis in tumoral or nodular form. Isolated soft tissue amyloidomas in individuals with end-stage renal disease on chronic hemodialysis is exceedingly rare, particularly in the era of advanced dialysis technologies. We report the case of a 55-year-old male with end-stage renal disease due to autosomal-dominant polycystic kidney disease, on HD for over 30 years, who was found to have soft-tissue, dialysis-related (β₂ -microglobulin) amyloidomas (DRA). He presented with painful, palpable masses within the thoracic and abdominal walls. Serum β₂ -microglobulin level was only mildly elevated at 24.9 mg/L. Biopsy confirmed amyloidosis with positivity for Congo Red staining and apple-green birefringence under polarized light. Amyloid subtyping with immunohistochemistry showed positive β₂ -microglobulin staining within the deposits. Conservative therapy involving pain management and close monitoring resulted in eventual improvement in symptoms and thus proved to be a viable option for treatment.

Assessment of left ventricular mass changes after arteriovenous fistula surgical banding in end-stage renal disease

Left ventricular hypertrophy (LVH) is a multifactorial complication frequently seen in patients with advanced chronic kidney disease. An arteriovenous fistula (AVF) is the preferred method for hemodialysis access. Once functional, AVFs demonstrate better patency rates and fewer complications when compared to other forms of vascular access. AVFs have been implicated in cardiac remodeling, but it is controversial whether those changes can be reversed by surgical ligation or blood flow reduction. In this study, we describe a cohort of asymptomatic patients with LVH who underwent AVF banding with a two-dimensional-echocardiogram done before and after the intervention to evaluate the association between AVF surgical banding and left ventricular mass (LVM) changes. Our results show that AVF surgical banding did not alter the left ventricular mass index (LVMI) with a mean prebanding LVMI of 70.3 ± 57.5 g/m² and mean postbanding LVMI of 81.9 ± 55.9 g/m², (P = 0.4). Our study shows that AVF flow reduction by surgical banding did not alter LVMI, and therefore LVH, in end-stage renal disease patients who have not yet shown clinical manifestations of cardiac disease.

ANCA associated vasculitis: experience of a tertiary care referral center

Background and objectives:

Anti-neutrophil cytoplasmic autoantibodies (ANCA) associated vasculitis is a small vessel vasculitis with insufficient epidemiologic estimates in the United States. We aimed to determine demographic and clinical features of ANCA associated vasculitis patients presenting to a large tertiary care referral center in Upstate New York. Design, setting, participants, and measurements: A retrospective analysis of cases with pauci-immune GN on renal biopsy and clinical diagnosis of ANCA vasculitis presenting over 11 years was conducted. Outcomes of interest were: demographics, ANCA antibody positivity, patient and renal survival, and regional trends.

Results:

986 biopsies were reviewed, 41 cases met the criteria for inclusion: 18 GPA, 19 MPA, and 4 double positive (anti-GBM disease plus ANCA vasculitis). Mean age at presentation was 52.4 years (SD 23.7), 23 (56%) were male and median creatinine was 2.6 mg/dL. The median patient follow up was 77 weeks (IQR 10 - 263 weeks), with a 3-month mortality rate of 5.7% and a 1-year estimated mortality rate of 12%. Thirteen patients required hemodialysis at the time of diagnosis; 7 patients came off dialysis, with median time to renal recovery of 4.86 weeks (IQR 1.57 - 23.85 weeks). C-ANCA positivity (p < 0.001) and C-ANCA plus PR3 antibody pairing (p = 0.005) was statistically significant in GPA versus MPA. P-ANCA positivity was observed in MPA versus GPA (p = 0.02) and double positive versus GPA (p = 0.002), with P-ANCA and MPO antibody pairing in MPA versus GPA (p = 0.044). Thirty-seven of the 41 cases were referred locally, 16 cases were from within a 15-mile radius of Albany, Schenectady, and Saratoga counties.

Conclusions:

ANCA vasculitis is associated with end stage renal disease and increased mortality. Our study suggests the possibility of higher regional incidence of pauci-immune GN in Upstate New York. Further studies should investigate the causes of clustering of cases to specific regions.

Detection of Atherosclerotic Cardiovascular Disease in Patients with Advanced Chronic Kidney Disease in the Cardiology and Nephrology Communities

BACKGROUND

Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of morbidity and mortality among patients with chronic kidney disease (CKD) with a glomerular filtration rate of < 60 mL/min/1.73 m2 body surface area. The availability of high-quality randomized controlled trial data to guide management for the population with CKD and ASCVD is limited. Understanding current practice patterns among providers caring for individuals with CKD and CVD is important in guiding future trial questions.

METHODS

A qualitative survey study was performed. An electronic survey regarding the diagnosis and management of CVD in patients with CKD was conducted using a convenience sample of 450 practicing nephrology and cardiology providers. The survey was administered using Qualtrics® (https://www.qualtrics.com).

RESULTS

There were a total of 113 responses, 81 of which were complete responses. More than 90% of the respondents acknowledged the importance of CVD as a cause of morbidity and mortality in patients with CKD. Outside the kidney transplant evaluation setting, 5% of the respondents would screen an asymptomatic patient with advanced CKD for ASCVD. Outside the kidney transplant evaluation scenario, the respondents did not opt for invasive management strategies in advanced CKD.

CONCLUSIONS

The survey results reveal a lack of consensus among providers caring for patients with advanced CKD about the management of ASCVD in this setting. Future randomized controlled trials will be needed to better inform the clinical management of ASCVD in these patients. The limitations of the study include its small sample size and the relatively low response rate among the respondents.

Prevalence of chronic kidney disease among patients undergoing transradial percutaneous coronary interventions

BACKGROUND

While transradial approach to conduct percutaneous coronary interventions offers multiple advantages, the procedure can cause radial artery damage and occlusion. Because radial artery is the preferred site for the creation of an arteriovenous fistula to provide dialysis, patients with chronic kidney disease are particularly dependent on radial artery for their long-term survival.

METHODS

In this retrospective study, we investigated the prevalence of chronic kidney disease in patients undergoing coronary interventions via radial artery. Stage of chronic kidney disease was based on estimated glomerular filtration rate and National Kidney Foundation - Kidney Disease Outcomes Quality Initiative guidelines.

RESULTS

A total of 497 patients undergoing transradial percutaneous coronary interventions were included. Over 70.4% (350/497) of the patients had chronic kidney disease. Stage II chronic kidney disease was observed in 243 (69%) patients (estimated glomerular filtration rate = 76.0 ± 8.4 mL/min). Stage III was observed in 93 (27%) patients (estimated glomerular filtration rate = 49 ± 7.5 mL/min). Stage IV chronic kidney disease was observed in 5 (1%) patients (estimated glomerular filtration rate = 25.6 ± 4.3 mL/min) and Stage V chronic kidney disease was observed in 9 (3%) patients (estimated glomerular filtration rate = 9.3 ± 3.5 mL/min). Overall, 107 of 350 patients (30%) had advanced chronic kidney disease, that is, stage III-V chronic kidney disease. Importantly, 14 of the 107 (13%) patients had either stage IV or V chronic kidney disease.

CONCLUSION

This study finds that nearly one-third of the patients undergoing transradial percutaneous coronary interventions have advanced chronic kidney disease. Because many of these patients may require dialysis, the use of radial artery to conduct percutaneous coronary interventions must be carefully considered in chronic kidney disease population.

The Role of Endovascular Stents in Dialysis Access Maintenance

Vascular stenosis is most often the culprit behind hemodialysis vascular access dysfunction, and although percutaneous transluminal angioplasty remains the gold standard treatment for vascular stenosis, over the past decade the use of stents as a treatment option has been on the rise. Aside from the 2 Food and Drug Administration-approved stent grafts for the treatment of venous graft anastomosis stenosis, use of all other stents in vascular access dysfunction is off-label. Kidney Disease Outcomes Quality Initiative recommends limiting stent use to specific conditions, such as elastic lesions and recurrent stenosis; otherwise, additional adapted indications are in procedure-related complications, such as grade 2 and 3 hematomas. Published reports have shown the potential use of stents in a variety of conditions leading to vascular access dysfunction, such as venous graft anastomosis stenosis, cephalic arch stenosis, central venous stenosis, dialysis access aneurysmal elimination, cardiac implantable electronic device-induced stenosis, and thrombosed arteriovenous grafts. Although further research is needed for many of these conditions, evidence for recommendations has been clear in some; for instance, we know now that stents should be avoided along cannulation sites and should not be used in eliminating dialysis access aneurysms. In this review article, we evaluate the available evidence for the use of stents in each of the aforementioned conditions leading to hemodialysis vascular access dysfunctions.

A meta-analysis of randomized clinical trials assessing hemodialysis access thrombosis based on access flow monitoring: where do we stand?

The National Kidney Foundation Kidney Disease Outcomes Quality Initiative recommends the routine use of hemodialysis arteriovenous (AV) access surveillance to detect hemodynamically significant stenoses and appropriately correct them to reduce the incidence of thrombosis and to improve accesses patency rates. Access blood flow monitoring is considered as one of the preferred surveillance method for both AV fistulas (AVF) and AV grafts (AVG); however, published studies have reported conflicting results of its utility that led healthcare professionals to doubt the benefits of this surveillance method. We performed a meta-analysis of the published randomized controlled trials (RCTs) of AV access surveillance using access blood flow monitoring. Our hypothesis was that access blood flow monitoring lowers the risk of AV access thrombosis and that the outcome differs between AVF and AVG. The estimated overall pooled risk ratio (RR) of thrombosis was 0.87 (95% confidence interval [CI], 0.67-1.13) favoring access blood flow monitoring. The pooled RR of thrombosis were 0.64 (95% CI, 0.41-1.01) and 1.06 (95% CI, 0.77-1.46) in the subgroups of only AVF and only AVG, respectively. Our results added to the uncertainty of access blood flow monitoring as a surveillance method of hemodialysis accesses.

A Simplified Approach to the Diagnosis of Atypical HUS: Clinical Considerations and Practical Implications

Although rare, atypical hemolytic-uremic syndrome (aHUS) carries a high morbidity and mortality. Widespread microvascular thrombosis, thrombocytopenia and microangiopathic hemolytic anemia are the hallmark of aHUS. Virtually any organ (particularly the kidney) can be a target for the devastating effects of this syndrome. Uncontrolled activation of the alternative pathway of the complement system lies at the heart of the pathogenesis of aHUS. While significant advances have been made in our understanding of aHUS, establishing timely diagnosis of this syndrome has been challenging. This, in part, is due to the absence of a sensitive and specific diagnostic test and a relatively lack of our familiarity with the syndrome. With the recent success and approval of a humanized monoclonal antibody (eculizumab) in the treatment of aHUS, prompt and accurate diagnosis is of paramount importance to limit the target organ injury. This article presents a simplified approach to establishing the diagnosis of aHUS.

Measurement of vessel diameter during angioplasty: are we accurately performing this task?

Vessel diameter is objectively measured by a lead ruler positioned in the fluoroscopic field and software calibration during angioplasty. We conducted a prospective study to evaluate the accuracy of lead ruler determination of vessel diameter. Chronic hemodialysis patients undergoing an angioplasty procedure were included in this study (n = 37). Vessel diameter was determined by calibrating the fluoroscopy machine to a ruler with lead markers placed in the fluoroscopic field. The same calibration was used to measure the fully effaced angioplasty balloon in its intravascular location. We compared the measured balloon diameter with the actual (manufacturer's) diameter. The approximate depth of the ruler from the measured vessel was also determined. Angioplasty balloons appeared 13.75-40.83% (mean 25.8% ± 7.015) smaller than the actual size of the balloon (p < 0.0001) when measured using a calibrated fluoroscopic machine. There was a tendency toward the fact that the bigger the distance between the ruler and the vessel (that contained the angioplasty balloon), the more likely the technique underestimated the size of the angioplasty balloon. Lead ruler method underestimates the diameter of the vessel. Recognizing such a discrepancy is important when determining the size of an angioplasty balloon or endovascular stent.

Balloon cinch deformity during angioplasty procedures: an indication for impending rupture

Percutaneous transluminal balloon angioplasty (PTA) is a commonly performed procedure for hemodialysis vascular access dysfunction including thrombosis. While PTA is generally safe, balloon rupture during the procedure is a potential complication. Because such a rupture can cause damage to the blood vessel, indication of an imminent balloon rupture might help avoid such a complication. This analysis reports on six PTA procedures that were complicated by balloon rupture. All cases demonstrated terminal (caudal/cranial) cinch deformation. There was a loss of sharp terminal tapering and its replacement with banana silhouette before the balloon rupture. Importantly, the contour deformation and balloon rupture occurred at a pressure that was lower than the rated burst pressure. The cinch deformity can be used as an indication for impending balloon rupture. We suggest deflation of balloons that demonstrate shape deformations to avoid vascular injury.

Blood pressure recordings during hemodialysis access interventions: implications for acute management

A retrospective study evaluating the pattern of blood pressure and its related complications before, during, and after percutaneous hemodialysis interventions was performed in patients presenting with asymptomatic hypertension. Hemodialysis patients undergoing percutaneous interventions including tunneled hemodialysis catheter insertion, percutaneous balloon angioplasty and thrombectomy procedure, and stage II hypertension (systolic blood pressure ≥160 mmHg) were included in this analysis. Blood pressure medications were not used while midazolam and fentanyl were routinely administered. Patients were followed for up to 4 weeks to monitor any complications. The mean blood pressure before, during, and after the procedures were 185 ± 18/96 ± 14, 172 ± 22/92 ± 15, and 153 ± 25/87 ± 14, respectively. There was a statistically significant difference between the blood pressure readings before and after the procedure (before = 185 ± 18/96 ± 14, after = 153 ± 25/87 ± 14; p = 0.001). None of the patients had a stroke, myocardial infarction, or acute pulmonary edema before, during, or after the procedure or during the 4-week follow-up period. A significant reduction in blood pressure was observed after the procedure without the administration of any antihypertensive medication. These results suggest that the reduction in blood pressure observed after percutaneous dialysis access interventions (particularly in the presence of midazolam and fentanyl) may make it unnecessary to treat asymptomatic hypertension prior to these procedures.

Radial artery harvest: a potential cause of arteriovenous access-associated hand ischemia

Hand ischemia has multiple causes. In this article, we report an additional factor that can induce hand ischemia in hemodialysis patients. A 64-year-old white man with coronary artery disease underwent a coronary artery bypass graft procedure using the left radial artery as the bypass graft. Several months later, a left extremity Gracz fistula was created for arteriovenous access. Ever since dialysis was performed via the fistula the patient has experienced a cold hand and pain during dialysis that was somewhat relieved by wearing a woolen glove while on dialysis. Absence of the radial artery in the context of an ipsilateral arteriovenous access was highlighted as a possible etiology. A complete arteriography to determine the presence of stenoses, distal arteriopathy, and true steal was recommended, but the patient refused to undergo any investigation or procedure and instead decided to continue wearing the glove during the treatment. A plan for close follow-up and possible interventions in the event of worsening pain/ulceration was agreed upon. Radial artery harvest can result in hand ischemia if an ipsilateral arteriovenous access is created. We suggest that the contralateral extremity should be considered if an arteriovenous access is required to minimize this risk of this phenomenon.