Improving outcomes in atherosclerotic renovascular disease: importance of clinical presentation and multi-disciplinary review

BACKGROUND AND OBJECTIVES

Atherosclerotic renal artery stenosis may cause hypertension, chronic kidney disease and heart failure, but large randomized control trials to date have shown no major additional benefit of renal revascularization over optimal medical management. However, these trials did not consider outcomes specifically in relation to clinical presentations. Given that atherosclerotic renal artery stenosis is a heterogenous condition, measures of success likely differ according to the clinical presentation. Our retrospective study objectives were to determine the effects of revascularization when applied to specific clinical presentations and after careful multi-disciplinary team review.

METHODS

All patients presenting to our centre and its referring hospitals with radiological findings of at least one renal artery stenosis > 50% between January 2015 and January 2020 were reviewed at the renovascular multi-disciplinary team meeting with revascularization considered in accordance with international guidelines, notably for patients with anatomically significant renal artery stenosis, adequately sized kidney and presentations with any of; deteriorating kidney function, heart failure syndrome, or uncontrollable hypertension. Optimal medical management was recommended for all patients which included lipid lowering agents, anti-platelets and anti-hypertensives targeting blood pressure ≤ 130/80 mmHg. The effect of revascularization was assessed according to the clinical presentation; blood pressure and number of agents in those with renovascular hypertension, delta glomerular filtration rate in those with ischaemic nephropathy and heart failure re-admissions in those with heart failure syndromes.

RESULTS

During this 5-year period, 127 patients with stenosis ≥ 50% were considered by the multidisciplinary team, with 57 undergoing revascularization (17 primarily for severe hypertension, 25 deteriorating kidney function, 6 heart failure syndrome and 9 for very severe anatomical stenosis). Seventy-nine percent of all revascularized patients had a positive outcome specific to their clinical presentation, with 82% of those with severe hypertension improving blood pressure control, 72% with progressive ischaemic nephropathy having attenuated GFR decline, and no further heart failure admissions in those with heart failure. Seventy-eight percent of patients revascularized for high grade stenosis alone had better blood pressure control with 55% also manifesting renal functional benefits.

CONCLUSIONS

Multi-disciplinary team discussion successfully identified a group of patients more likely to benefit from revascularization based on 3 key factors: clinical presentation, severity of the renal artery lesion and the state of the kidney beyond the stenotic lesion. In this way, a large proportion of patients can clinically improve after revascularization if their outcomes are considered according to the nature of their clinical presentation.

Incidence, Risk Factors, and Outcomes of De Novo Malignancy following Kidney Transplantation

Introduction: Post-transplant malignancy is a significant cause of morbidity and mortality following kidney transplantation often emerging after medium- to long-term follow-up. To understand the risk factors for the development of de novo post-transplant malignancy (DPTM), this study aimed to assess the incidence, risk factors, and outcomes of DPTM at a single nephrology centre over two decades. Methods: This retrospective cohort study included 963 kidney transplant recipients who underwent kidney transplantation between January 2000 and December 2020 and followed up over a median follow-up of 7.1 years (IQR 3.9-11.4). Cox regression models were used to identify the significant risk factors of DPTM development, the association of DPTM with graft survival, and mortality with a functioning graft. Results: In total, 8.1% of transplant recipients developed DPTM, and the DPTM incidence rate was 14.7 per 100 patient-years. There was a higher mean age observed in the DPTM group (53 vs. 47 years, p < 0.001). The most affected organ systems were genitourinary (32.1%), gastrointestinal (24.4%), and lymphoproliferative (20.5%). Multivariate Cox analysis identified older age at transplant (aHR 9.51, 95%CI: 2.60-34.87, p < 0.001) and pre-existing glomerulonephritis (aHR 3.27, 95%CI: 1.10-9.77, p = 0.03) as significant risk factors for DPTM. Older age was significantly associated with poorer graft survival (aHR 8.71, 95%CI: 3.77-20.20, p < 0.001). When age was excluded from the multivariate Cox model, DPTM emerged as a significant risk factor for poor survival (aHR 1.76, 95%CI: 1.17-2.63, p = 0.006). Conclusion: These findings underscore the need for tailored screening, prevention, and management strategies to address DPTM in an aging and immunosuppressed kidney transplant population.

The effect of primary renal disease upon outcomes after renal transplant

BACKGROUND

This study investigated whether nature of primary renal disease affects clinical outcomes after renal transplantation at a single center in the United Kingdom.

METHODS

This was a retrospective cohort study of 961 renal transplant recipients followed up at a large renal center from 2000 to 2020. Separation of diseases responsible for end-stage kidney disease included glomerulonephritis, diabetic kidney disease, hypertensive nephropathy, autosomal dominant polycystic kidney disease, unknown cause, other causes and chronic pyelonephritis. Outcome data included graft loss, cardiovascular events, malignancy, post-transplant diabetes mellitus and death, analyzed according to primary disease type.

RESULTS

The mean age at transplantation was 47.3 years. During a mean follow-up of 7.6 years, 18% of the overall cohort died corresponding to an annualised mortality rate of 2.3%. Death with a functioning graft occurred at a rate of 2.1% per annum, with the highest incidence observed in in patients with diabetic kidney disease (4.1%/year). Post-transplant cardiovascular events occurred in 21% of recipients (2.8% per year), again highest in recipients with diabetic kidney disease (5.1%/year) and hypertensive nephropathy (4.5%/year). Post-transplant diabetes mellitus manifested in 19% of the cohort at an annualized rate of2.1% while cancer incidence stood at 9% with an annualized rate of 1.1% . Graft loss occurred in 6.8% of recipients at the rate of1.2% per year with chronic allograft injury, acute rejection and recurrent glomerulonephritis being the predominant causative factors. Median + IQR dialysis-free survival of the whole cohort was 16.2 (9.9 - > 20) years, being shortest for diabetic kidney disease (11.0 years) and greatest for autosomal dominant polycystic kidney disease (18.2 years) .The collective mean decline in eGFR over time was -1.14ml/min/year. Recipients with Pre-transplant diabetic kidney disease exhibited the fastest rate of decline(-2.1ml/min/year) a statistically significant difference in comparison to the other native kidney diseases with Autosomal dominant polycystic kidney disease exhibiting the lowest rate of decline(-0.05ml/min/year) CONCLUSION: Primary renal disease can influence the outcome after renal transplantation, with patients with prior diabetic kidney disease having the poorest outcome in terms of dialysis-free survival and loss of transplant function. Autosomal polycystic kidney disease, other cause and unknown cause had the best outcomes compared to other primary renal disease groups.

Clostridioides difficile Infection in Kidney Transplant Recipients

Clostridioides difficile (C. difficile) is a bacterial organism that typically infects the colon, which has had its homeostasis of healthy gut microbiota disrupted by antibiotics or other interventions. Patients with kidney transplantation are a group that are susceptible to C. difficile infection (CDI) and have poorer outcomes with CDI given that they conventionally require long-term immunosuppression to minimize their risk of graft rejection, weakening their responses to infection. Recognizing the risk factors and complex pathophysiological processes that exist between immunosuppression, dysbiosis, and CDI is important when making crucial clinical decisions surrounding the management of this vulnerable patient cohort. Despite the clinical importance of this topic, there are few studies that have evaluated CDI in the context of kidney transplant recipients and other solid organ transplant populations. The current recommendations on CDI management in kidney transplant and solid organ transplant recipients are mostly extrapolated from data relating to CDI management in the general population. We provide a narrative review that discusses the available evidence examining CDI in solid organ transplant recipients, with a particular focus on the kidney transplant recipient, from the epidemiology of CDI, clinical features and implications of CDI, potential risk factors of CDI, and, ultimately, prevention and management strategies for CDI, with the aim of providing areas for future research development in this topic area.

Hepatocardiorenal syndrome in liver cirrhosis: Recognition of a new entity?

Emerging evidence and perspectives have pointed towards the heart playing an important role in hepatorenal syndrome (HRS), outside of conventional understanding that liver cirrhosis is traditionally considered the sole origin of a cascade of pathophysiological mechanisms directly affecting the kidneys in this context. In the absence of established heart disease, cirrhotic cardiomyopathy may occur more frequently in those with liver cirrhosis and kidney disease. It is a specific form of cardiac dysfunction characterized by blunted contractile responsiveness to stress stimuli and altered diastolic relaxation with electrophysiological abnormalities. Despite the clinical description of these potential cardiac-related complications of the liver, the role of the heart has traditionally been an overlooked aspect of circulatory dysfunction in HRS. Yet from a physiological sense, temporality (prior onset) of cardiorenal interactions in HRS and positive effects stemming from portosystemic shunting demonstrated an important role of the heart in the development and progression of kidney dysfunction in cirrhotic patients. In this review, we discuss current concepts surrounding how the heart may influence the development and progression of HRS, and the role of systemic inflammation and endothelial dysfunction causing circulatory dysfunction within this setting. The temporality of heart and kidney dysfunction in HRS will be discussed. For a subgroup of patients who receive portosystemic shunting, the dynamics of cardiorenal interactions following treatment is reviewed. Continued research to determine the unknowns in this topic is anticipated, hopefully to further clarify the intricacies surrounding the liver-heart-kidney connection and improve strategies for management.

Mortality and Renal Outcomes Are Impacted by Obesity in Cardiorenal Metabolic Disease but Not in People with Concomitant Diabetes Mellitus

INTRODUCTION

Mounting evidence in the literature describes a reverse association, whereby obesity may have a protective effect on mortality - the "obesity paradox." Due to the significant overlap between elements of cardiorenal metabolic disease, we examined the effects of obesity on outcomes in a cohort of patients with non-dialysis chronic kidney disease (ND-CKD) by grouping patients according to their level of cardiometabolic co-morbidity to reduce the risk of bias.

METHODS

This study was undertaken on all patients with a documented body mass index (BMI) in the Salford Kidney Study database from October 2002 until December 2016. Patients were grouped according to their BMI into normal weight, overweight, and obese, and also according to their level of co-morbidity into 4 groups: group 1 had CKD only; group 2 had CKD and heart failure (HF); group 3 had CKD and diabetes mellitus (DM); and group 4 had CKD, DM, and HF. Univariate and multivariate Cox regression analyses were performed.

RESULTS

A total of 2,416 patients were included in the analysis. The median age was 67.3 years, 61.8% were male, and 96.4% were Caucasian. Obesity was associated with a lower incidence of combined outcomes in patients with ND-CKD who did not have DM (hazard ratio [HR] 0.74; p = <0.001 and HR 0.48; p = 0.008 for CKD alone and CKD + HF groups, respectively). This protective effect remained significant after correcting for major factors. In patients with ND-CKD and DM, there was no difference in all-cause mortality between the normal weight group and the obesity groups.

CONCLUSION

Obesity may be protective against adverse outcomes only in groups 1 (CKD alone) and 2 (CKD + HF). This "protective" effect was not seen in patients who had concomitant diabetes. These data suggest that diabetes is a potent predictor of adverse outcomes, irrespective of BMI; however, in patients without diabetes, obesity may play a protective role.

Antihypertensive prescribing patterns in non-dialysis dependent chronic kidney disease: Findings from the Salford Kidney Study

BACKGROUND

Hypertension is commonly observed in patients living with chronic kidney disease (CKD). Finding an optimal treatment regime remains challenging due to the complex bidirectional cause-and-effect relationship between hypertension and CKD. There remains variability in antihypertensive treatment practices.

AIM

To analyze data from the Salford Kidney Study database in relation to antihypertensive prescribing patterns amongst CKD patients.

METHODS

The Salford Kidney Study is an ongoing prospective study that has been recruiting CKD patients since 2002. All patients are followed up annually, and their medical records including the list of medications are updated until they reach study endpoints [starting on renal replacement therapy or reaching estimated glomerular filtration rate (eGFR) expressed as mL/min/1.73 m2 ≤ 10 mL/min/1.73 m2, or the last follow-up date, or data lock on December 31, 2021, or death]. Data on antihypertensive prescription practices in correspondence to baseline eGFR, urine albumin-creatinine ratio, primary CKD aetiology, and cardiovascular disease were evaluated. Associations between patients who were prescribed three or more antihypertensive agents and their clinical outcomes were studied by Cox regression analysis. Kaplan-Meier analysis demonstrated differences in survival probabilities.

RESULTS

Three thousand two hundred and thirty non-dialysis-dependent CKD patients with data collected between October 2002 and December 2019 were included. The median age was 65 years. A greater proportion of patients were taking three or more antihypertensive agents with advancing CKD stages (53% of eGFR ≤ 15 mL/min/1.73 m2 vs 26% of eGFR ≥ 60 mL/min/1.73 m2, P < 0.001). An increased number of patients receiving more classes of antihypertensive agents was observed as the urine albumin-creatinine ratio category increased (category A3: 62% vs category A1: 40%, P < 0.001), with the upward trends particularly noticeable in the number of individuals prescribed renin angiotensin system blockers. The prescription of three or more antihypertensive agents was associated with all-cause mortality, independent of blood pressure control (hazard ratio: 1.15; 95% confidence interval: 1.04-1.27, P = 0.006). Kaplan-Meier analysis illustrated significant differences in survival outcomes between patients with three or more and those with less than three antihypertensive agents prescribed (log-rank, P < 0.001).

CONCLUSION

Antihypertensive prescribing patterns in the Salford Kidney Study based on CKD stage were consistent with expectations from the current United Kingdom National Institute of Health and Care Excellence guideline algorithm. Outcomes were poorer in patients with poor blood pressure control despite being on multiple antihypertensive agents. Continued research is required to bridge remaining variations in hypertension treatment practices worldwide.

The epidemiology of primary FSGS including cluster analysis over a 20-year period

INTRODUCTION

Focal segmental glomerulosclerosis (FSGS) is one of the leading causes of nephrotic syndrome in adults. This epidemiological study describes a renal centre's 20-year experience of primary FSGS.

METHODS

Patients were identified with a diagnosis of primary FSGS after exclusion of known secondary causes. In this retrospective observational study, data was collected for baseline demographics, immunosuppression and outcomes. A two-step cluster analysis was used to identify natural groupings within the dataset.

RESULTS

The total cohort was made up of 87 patients. Those who received immunosuppression had lower median serum albumin than those who did not- 23g/L vs 40g/L (p<0.001) and higher median urine protein creatinine ratios (uPCR)- 795mg/mmol vs 318mg/mmol (p <0.001). They were more likely to achieve complete remission (62% vs 40%, p=0.041), but relapsed more 48.6% vs 22% (p=0.027). Overall 5 year mortality was 10.3% and 5 year progression to RRT was seen in 17.2%. Complete remission was observed in 49.4%. The 2-step cluster analysis separated the cohort into 3 clusters: cluster 1 (n=26) with 'nephrotic-range proteinuria'; cluster 2 (n=43) with 'non-nephrotic-range proteinuria'; and cluster 3 (n=18) with nephrotic syndrome. Immunosuppression use was comparable in clusters 1 and 3, but lower in cluster 2 (77.8% and 69.2% vs 11.6%, p<0.001). Rates of complete remission were greatest in clusters 1 and 3 vs cluster 2: 57.7% and 66.7% vs 37.2%.

CONCLUSION

People who received immunosuppression had lower serum albumin and achieved remission more frequently, but were also prone to relapse. Our cluster analysis highlighted 3 FSGS phenotypes: a nephrotic cluster that clearly require immunosuppression; a cohort with preserved serum albumin and non-nephrotic range proteinuria who will benefit from supportive care; and lastly a cluster with heavy proteinuria but serum albumin > 30g/L. This group may still have immune mediated disease and thus could potentially benefit from immunosuppression.

TRIAL REGISTRATION

This study protocol was reviewed and approved by the 'Research and Innovation committee of the Northern Care Alliance NHS Group', study approval number (Ref: ID 22HIP54).

Using Prior Knowledge on Systems Through PBPK to Gain Further Insight into Routine Clinical Data on Trough Concentrations: The Case of Tacrolimus in Chronic Kidney Disease

BACKGROUND

Routine therapeutic drug monitoring (TDM) relies heavily on measuring trough drug concentrations. Trough concentrations are affected not only by drug bioavailability and clearance, but also by various patient and disease factors and the volume of distribution. This often makes interpreting differences in drug exposure from trough data challenging. This study aimed to combine the advantages of top-down analysis of therapeutic drug monitoring data with bottom-up physiologically-based pharmacokinetic (PBPK) modeling to investigate the effect of declining renal function in chronic kidney disease (CKD) on the nonrenal intrinsic metabolic clearance ( CLint ) of tacrolimus as a case example.

METHODS

Data on biochemistry, demographics, and kidney function, along with 1167 tacrolimus trough concentrations for 40 renal transplant patients, were collected from the Salford Royal Hospital's database. A reduced PBPK model was developed to estimate CLint for each patient. Personalized unbound fractions, blood-to-plasma ratios, and drug affinities for various tissues were used as priors to estimate the apparent volume of distribution. Kidney function based on the estimated glomerular filtration rate ( eGFR ) was assessed as a covariate for CLint using the stochastic approximation of expectation and maximization method.

RESULTS

At baseline, the median (interquartile range) eGFR was 45 (34.5-55.5) mL/min/1.73 m 2 . A significant but weak correlation was observed between tacrolimus CLint and eGFR (r = 0.2, P < 0.001). The CLint declined gradually (up to 36%) with CKD progression. Tacrolimus CLint did not differ significantly between stable and failing transplant patients.

CONCLUSIONS

Kidney function deterioration in CKD can affect nonrenal CLint for drugs that undergo extensive hepatic metabolism, such as tacrolimus, with critical implications in clinical practice. This study demonstrates the advantages of combining prior system information (via PBPK) to investigate covariate effects in sparse real-world datasets.

Delivering Personalized, Goal-Directed Care to Older Patients Receiving Peritoneal Dialysis

Background

An aging population living with chronic kidney disease and progressing to kidney failure, subsequently receiving peritoneal dialysis (PD) is growing. A significant proportion of these patients are also living with multi-morbidities and some degree of frailty. Recent practice recommendations from the International Society of Peritoneal Dialysis advocate for high-quality, goal-directed PD prescription, and the Standardized Outcomes of Nephrology-PD initiative emphasized the need for an individualized, goal-based care approach in all patients receiving PD treatment. In older patients, this approach to PD care is even more important. A frailty screening assessment, followed by a comprehensive geriatric assessment (CGA) prior to PD initiation and when dictated by change in relevant circumstances is paramount in tailoring PD care and prescription according to the needs, life goals, as well as clinical status of older patients with kidney failure.

Summary

Our review aimed to summarize the different dimensions to be taken into account when delivering PD care to the older patient - from frailty screening and CGA in older patients receiving PD to employing a personalized, goal-directed PD prescription strategy, to preserving residual kidney function, optimizing blood pressure (BP) control, and managing anemia, to addressing symptom burden, to managing nutritional intake and promoting physical exercise, and to explore telehealth opportunities for the older PD population.

Key Messages

What matters most to older PD patients may not be simply extending survival, but more importantly, to be living comfortably on PD treatment with minimal symptom burden in a home environment and to minimize treatment complications.

Maintaining Renin-Angiotensin-Aldosterone System Inhibitor Treatment with Patiromer in Hyperkalaemic Chronic Kidney Disease Patients: Comparison of a Propensity-Matched Real-World Population with AMETHYST-DN

INTRODUCTION

Guideline-directed renin-angiotensin-aldosterone system inhibitor (RAASi) therapy is rarely achieved in clinical settings, often due to hyperkalaemia. We assessed the potassium binder, patiromer, on continuation of RAASi therapy in hyperkalaemic patients with chronic kidney disease (CKD) and type 2 diabetes mellitus (T2DM) in the AMETHYST-DN trial, propensity score-matched to a real-world cohort not receiving patiromer (Salford Kidney Study).

METHODS

The phase 2, open-label AMETHYST-DN trial (NCT01371747) randomized 304 adults with CKD on RAASi, T2DM, hyperkalaemia (serum potassium [sK+] >5.0 mEq/L), and hypertension to receive patiromer, 8.4-33.6 g/day for 12 months. Patients underwent propensity score matching for systolic blood pressure (BP), heart failure status, and estimated glomerular filtration rate (eGFR), with 321 patients with CKD, T2DM, hyperkalaemia, and on RAASi from a prospective CKD cohort (Salford Kidney Study). Changes in RAASi utilization, sK+, BP, proteinuria, and eGFR during 12-month follow-up were assessed by Mann-Whitney U or χ2 tests.

RESULTS

Matching produced 135:135 patients with no significant differences in age, sex, systolic BP, sK+, eGFR, or heart failure status, although differences in diastolic BP remained (p < 0.001). After 12 months, 100% of AMETHYST-DN patients receiving patiromer remained on RAASi therapy, whereas 38.5% of the Salford Kidney Cohort discontinued RAASi (p < 0.001); hyperkalaemia contributed in 16% of patients (42% of RAASi discontinuations). Significantly greater reductions in sK+ and BP, but not proteinuria or eGFR, were observed in AMETHYST-DN, compared with Salford Kidney Study patients (p < 0.05).

CONCLUSIONS

These results demonstrate the benefit of patiromer for sK+ management to enable RAASi use while revealing beneficial effects on BP.

Risk factors for infective endocarditis in patients receiving hemodialysis: A propensity score matched cohort study

In patients receiving hemodialysis, infective endocarditis (IE) may present in a similar way to other causes of bacteremia, which may delay early diagnosis and can lead to worse outcomes. In this study, we aimed to identify the risk factors for IE in hemodialysis patients with bacteremia. This study was conducted on all patients diagnosed with IE and receiving hemodialysis between 2005 and 2018 in Salford Royal Hospital. Patients with IE were propensity score matched with similar hemodialysis patients with episodes of bacteremia between 2011 and 2015 (non-IE bacteremic (NIEB)). Logistic regression analysis was used to predict the risk factors associated with infective endocarditis. There were 35 cases of IE, and these were propensity matched with 70 NIEB cases. The median age of the patients was 65 years with a predominance of males (60%). The IE group had higher peak C-reactive protein compared to the NIEB group (median, 253 mg/L vs. 152, p = 0.001). Patients with IE had a longer duration of prior dialysis catheter use than NIEB patients (150 vs. 28.5 days: p = 0.004). IE patients had a much higher 30-day mortality rate (37.1% vs. 17.1%, p = 0.023). Logistic regression analysis showed previous valvular heart disease (OR: 29.7; p < 0.001), and a higher baseline C-reactive protein (OR: 1.01; p = 0.001) as significant predictors for infective endocarditis. Bacteremia in patients receiving hemodialysis through a catheter access should be actively investigated with a high index of suspicion for infective endocarditis, particularly in those with known valvular heart disease and a higher baseline C-reactive protein.

The Role of PLA2R in Primary Membranous Nephropathy: Do We Still Need a Kidney Biopsy?

Membranous nephropathy (MN) is the most prevalent cause of nephrotic syndrome amongst the non-diabetic adult population. A fifth of idiopathic nephrotic syndrome cases can be attributed to MN, rising to more than 40% in older patients over 60 years. Most MN cases are classified as being of a primary cause, where there is absence of a secondary disease process explaining its manifestation. Traditionally, the standard approach of diagnosing MN involves performing a kidney biopsy as histological evaluation offers not only conclusive evidence of the diagnosis but also provides valuable information regarding disease chronicity and the presence of any other kidney histopathological features. Nevertheless, kidney biopsy is an invasive procedure which poses risks for the patient including bleeding and pain and bears greater costs for the health system. The identification of the phospholipase A2 receptor (PLA2R) antigen in 2009 was a landmark discovery, one which has evolved our understanding of the disease processes in MN and subsequently our management approach of this condition. Antibodies against PLA2R (PLA2RAb) have since emerged as an attractive non-invasive test option to be applied for the diagnosis and prognostication of primary MN. However, much debate and unknowns remain about the accuracy and reliability of testing for PLA2RAb across various primary MN scenarios. We provide a review summarizing the historical journey of PLA2R in relation to its significance in primary MN and, more importantly, evidence emerging over the years which contemplated the role of PLA2RAb as a diagnostic and prognostic tool in primary MN.

COVID-19 Infection and Vaccination and Its Relation to Amyloidosis: What Do We Know Currently?

Amyloidosis is a complex disorder characterized by deposited insoluble fibrillar proteins which misfold into β-pleated sheets. The pathogenesis of amyloidosis can vary but can be the result of immune dysregulation that occurs from sustained high inflammatory states, often known as AA amyloidosis. Multi-organ involvement including hepatic, gastrointestinal, renal, cardiac and immunological pathological manifestations has been observed amongst individuals presenting with amyloidosis. The recent global pandemic of severe acute respiratory syndrome coronavirus 2, also referred to as coronavirus 2019 (COVID-19), has been shown to be associated with multiple health complications, many of which are similar to those seen in amyloidosis. Though COVID-19 is recognized primarily as a respiratory disease, it has since been found to have a range of extra-pulmonary manifestations, many of which are observed in patients with amyloidosis. These include features of oxidative stress, chronic inflammation and thrombotic risks. It is well known that viral illnesses have been associated with the triggering of autoimmune conditions of which amyloidosis is no different. Over the recent months, reports of new-onset and relapsed disease following COVID-19 infection and vaccination have been published. Despite this, the exact pathophysiological associations of COVID-19 and amyloidosis remain unclear. We present a scoping review based on our systematic search of available evidence relating to amyloidosis, COVID-19 infection and COVID-19 vaccination, evaluating current perspectives and providing insight into knowledge gaps that still needs to be addressed going forward.

Physiological Associations between Vitamin B Deficiency and Diabetic Kidney Disease

The number of people living with chronic kidney disease (CKD) is growing as our global population continues to expand. With aging, diabetes, and cardiovascular disease being major harbingers of kidney disease, the number of people diagnosed with diabetic kidney disease (DKD) has grown concurrently. Poor clinical outcomes in DKD could be influenced by an array of factors-inadequate glycemic control, obesity, metabolic acidosis, anemia, cellular senescence, infection and inflammation, cognitive impairment, reduced physical exercise threshold, and, importantly, malnutrition contributing to protein-energy wasting, sarcopenia, and frailty. Amongst the various causes of malnutrition in DKD, the metabolic mechanisms of vitamin B (B1 (Thiamine), B2 (Riboflavin), B3 (Niacin/Nicotinamide), B5 (Pantothenic Acid), B6 (Pyridoxine), B8 (Biotin), B9 (Folate), and B12 (Cobalamin)) deficiency and its clinical impact has garnered greater scientific interest over the past decade. There remains extensive debate on the biochemical intricacies of vitamin B metabolic pathways and how their deficiencies may affect the development of CKD, diabetes, and subsequently DKD, and vice-versa. Our article provides a review of updated evidence on the biochemical and physiological properties of the vitamin B sub-forms in normal states, and how vitamin B deficiency and defects in their metabolic pathways may influence CKD/DKD pathophysiology, and in reverse how CKD/DKD progression may affect vitamin B metabolism. We hope our article increases awareness of vitamin B deficiency in DKD and the complex physiological associations that exist between vitamin B deficiency, diabetes, and CKD. Further research efforts are needed going forward to address the knowledge gaps on this topic.

Major cardiovascular events and subsequent risk of kidney failure with replacement therapy: a CKD Prognosis Consortium study

AIMS

Chronic kidney disease (CKD) increases risk of cardiovascular disease (CVD). Less is known about how CVD associates with future risk of kidney failure with replacement therapy (KFRT).

METHODS AND RESULTS

The study included 25 903 761 individuals from the CKD Prognosis Consortium with known baseline estimated glomerular filtration rate (eGFR) and evaluated the impact of prevalent and incident coronary heart disease (CHD), stroke, heart failure (HF), and atrial fibrillation (AF) events as time-varying exposures on KFRT outcomes. Mean age was 53 (standard deviation 17) years and mean eGFR was 89 mL/min/1.73 m2, 15% had diabetes and 8.4% had urinary albumin-to-creatinine ratio (ACR) available (median 13 mg/g); 9.5% had prevalent CHD, 3.2% prior stroke, 3.3% HF, and 4.4% prior AF. During follow-up, there were 269 142 CHD, 311 021 stroke, 712 556 HF, and 605 596 AF incident events and 101 044 (0.4%) patients experienced KFRT. Both prevalent and incident CVD were associated with subsequent KFRT with adjusted hazard ratios (HRs) of 3.1 [95% confidence interval (CI): 2.9-3.3], 2.0 (1.9-2.1), 4.5 (4.2-4.9), 2.8 (2.7-3.1) after incident CHD, stroke, HF and AF, respectively. HRs were highest in first 3 months post-CVD incidence declining to baseline after 3 years. Incident HF hospitalizations showed the strongest association with KFRT [HR 46 (95% CI: 43-50) within 3 months] after adjustment for other CVD subtype incidence.

CONCLUSION

Incident CVD events strongly and independently associate with future KFRT risk, most notably after HF, then CHD, stroke, and AF. Optimal strategies for addressing the dramatic risk of KFRT following CVD events are needed.

COVID-19 in Elderly Patients Receiving Haemodialysis: A Current Review

There is an increased incidence of elderly adults diagnosed with kidney failure as our global aging population continues to expand. Hence, the number of elderly adults indicated for kidney replacement therapy is also increasing simultaneously. Haemodialysis initiation is more commonly observed in comparison to kidney transplantation and peritoneal dialysis for the elderly. The onset of the coronavirus 2019 (COVID-19) pandemic brought new paradigms and insights for the care of this patient population. Elderly patients receiving haemodialysis have been identified as high-risk groups for poor COVID-19 outcomes. Age, immunosenescence, impaired response to COVID-19 vaccination, increased exposure to sources of COVID-19 infection and thrombotic risks during dialysis are key factors which demonstrated significant associations with COVID-19 incidence, severity and mortality for this patient group. Recent findings suggest that preventative measures such as regular screening and, if needed, isolation in COVID-19-positive cases, alongside the fulfillment of COVID-19 vaccination programs is an integral strategy to reduce the number of COVID-19 cases and consequential complications from COVID-19, particularly for high-risk groups such as elderly haemodialysis patients. The COVID-19 pandemic brought about the rapid development and repurposing of a number of medications to treat patients in the viral and inflammatory stages of their disease. However, elderly haemodialysis patients were grossly unrepresented in many of these trials. We review the evidence for contemporary treatments for COVID-19 in this population to provide clinicians with an up-to-date guide. We hope our article increases awareness on the associations and impact of COVID-19 for the elderly haemodialysis population, and encourage research efforts to address knowledge gaps in this topical area.

Is It Time to Integrate Frailty Assessment in Onconephrology?

Simple Summary

There are an increasing number of older people living with kidney cancer and/or cancer and kidney disease worldwide, sparking a wider discussion on the impact of frailty and the clinical significance of conducting frailty assessments for this patient population. We provide an update on the current evidence related to frailty assessment in onconephrology and identify areas where further research efforts are anticipated to address knowledge gaps within this topic.

Abstract

Onconephrology has emerged as a novel sub-specialty of nephrology dedicated to the intersection between the kidney and cancer. This intersection is broad and includes a number of important areas of focus, including concurrent chronic kidney disease (CKD) and cancer, acute kidney complications of cancer, and cancer-treatment-induced nephrotoxicity. The importance of onconephrology is even more evident when considering the global growth in the population of older adults, many of whom are living with some degree of frailty. Furthermore, a considerable proportion of older adults have CKD (some of whom eventually progress to kidney failure) and are at high risk of developing solid tumour and hematologic malignancies. Specific to kidney disease, the association between frailty status and kidney disease has been explored in depth, and tools to capture frailty can be used to guide the management and prognostication of older adults living with kidney failure. Whilst there is emerging data regarding the assessment and impact of frailty in onconephrology, there remains a relative paucity of knowledge within this topic. In this article, we evaluate the definition and operationalization of frailty and discuss the significance of frailty within onconephrology. We review evidence on current approaches to assessing frailty in onconephrology and discuss potential developments and future directions regarding the utilization of frailty in this patient population. A greater awareness of the intersections and interactions between frailty and onconephrology and further efforts to integrate frailty assessment in onconephrology to optimize the delivery of realistic and goal-directed management strategies for patients is needed.

The association between iron deficiency and outcomes: a secondary analysis of the intravenous iron therapy to treat iron deficiency anaemia in patients undergoing major abdominal surgery (PREVENTT) trial

In the intravenous iron therapy to treat iron deficiency anaemia in patients undergoing major abdominal surgery (PREVENTT) trial, the use of intravenous iron did not reduce the need for blood transfusion or reduce patient complications or length of hospital stay. As part of the trial protocol, serum was collected at randomisation and on the day of surgery. These samples were analysed in a central laboratory for markers of iron deficiency. We performed a secondary analysis to explore the potential interactions between pre-operative markers of iron deficiency and intervention status on the trial outcome measures. Absolute iron deficiency was defined as ferritin <30 μg.l^-1 ; functional iron deficiency as ferritin 30-100 μg.l^-1 or transferrin saturation < 20%; and the remainder as non-iron deficient. Interactions were estimated using generalised linear models that included different subgroup indicators of baseline iron status. Co-primary endpoints were blood transfusion or death and number of blood transfusions, from randomisation to 30 days postoperatively. Secondary endpoints included peri-operative change in haemoglobin, postoperative complications and length of hospital stay. Most patients had iron deficiency (369/452 [82%]) at randomisation; one-third had absolute iron deficiency (144/452 [32%]) and half had functional iron deficiency (225/452 [50%]). The change in pre-operative haemoglobin with intravenous iron compared with placebo was greatest in patients with absolute iron deficiency, mean difference 8.9 g.l^-1 , 95%CI 5.3-12.5; moderate in functional iron deficiency, mean difference 2.8 g.l^-1 , 95%CI -0.1 to 5.7; and with little change seen in those patients who were non-iron deficient. Subgroup analyses did not suggest that intravenous iron compared with placebo reduced the likelihood of death or blood transfusion at 30 days differentially across subgroups according to baseline ferritin (p = 0.33 for interaction), transferrin saturation (p = 0.13) or in combination (p = 0.45), or for the number of blood transfusions (p = 0.06, 0.29, and 0.39, respectively). There was no beneficial effect of the use of intravenous iron compared with placebo, regardless of the metrics to diagnose iron deficiency, on postoperative complications or length of hospital stay.

Including measures of chronic kidney disease to improve cardiovascular risk prediction by SCORE2 and SCORE2-OP

AIMS

The 2021 European Society of Cardiology (ESC) guideline on cardiovascular disease (CVD) prevention categorizes moderate and severe chronic kidney disease (CKD) as high and very-high CVD risk status regardless of other factors like age and does not include estimated glomerular filtration rate (eGFR) and albuminuria in its algorithms, systemic coronary risk estimation 2 (SCORE2) and systemic coronary risk estimation 2 in older persons (SCORE2-OP), to predict CVD risk. We developed and validated an 'Add-on' to incorporate CKD measures into these algorithms, using a validated approach.

METHODS

In 3,054 840 participants from 34 datasets, we developed three Add-ons [eGFR only, eGFR + urinary albumin-to-creatinine ratio (ACR) (the primary Add-on), and eGFR + dipstick proteinuria] for SCORE2 and SCORE2-OP. We validated C-statistics and net reclassification improvement (NRI), accounting for competing risk of non-CVD death, in 5,997 719 participants from 34 different datasets.

RESULTS

In the target population of SCORE2 and SCORE2-OP without diabetes, the CKD Add-on (eGFR only) and CKD Add-on (eGFR + ACR) improved C-statistic by 0.006 (95%CI 0.004-0.008) and 0.016 (0.010-0.023), respectively, for SCORE2 and 0.012 (0.009-0.015) and 0.024 (0.014-0.035), respectively, for SCORE2-OP. Similar results were seen when we included individuals with diabetes and tested the CKD Add-on (eGFR + dipstick). In 57 485 European participants with CKD, SCORE2 or SCORE2-OP with a CKD Add-on showed a significant NRI [e.g. 0.100 (0.062-0.138) for SCORE2] compared to the qualitative approach in the ESC guideline.

CONCLUSION

Our Add-ons with CKD measures improved CVD risk prediction beyond SCORE2 and SCORE2-OP. This approach will help clinicians and patients with CKD refine risk prediction and further personalize preventive therapies for CVD.

Peritoneal dialysis-associated peritonitis presenting with Ralstonia pickettii infection: A novel series of three cases during the COVID-19 pandemic

Peritoneal dialysis (PD)-associated peritonitis secondary to Ralstonia infection is very rare. Ralstonia pickettii is an organism that can grow in contaminated saline, water, chlorhexidine, and other medical products used in laboratories and the clinical setting. Infective endocarditis, prosthetic joint, and severe chest infections are previously reported with R. pickettii infection. We report a novel series of three cases diagnosed with PD-associated peritonitis caused by R. pickettii, where the cases appeared consecutively to our unit during a span of 4 weeks. During the COVID-19 pandemic, there were increased uses of non-sterile gloves by clinical staff as a form of personal protective equipment throughout patient interaction and PD exchange, as recommended by local hospital policy for all staff attending to patient care. A multidisciplinary team root cause analysis of our cases suggested non-sterile gloves being the likely source of environmental contamination, leading to PD-associated peritonitis caused by R. pickettii in this scenario.

COVID-19 and hepatorenal syndrome

Coronavirus disease 2019 (COVID-19) is a highly infectious disease which emerged into a global pandemic. Although it primarily causes respiratory symptoms for affected patients, COVID-19 was shown to have multi-organ manifestations. Elevated liver enzymes appear to be commonly observed during the course of COVID-19, and there have been numerous reports of liver injury secondary to COVID-19 infection. It has been established that patients with pre-existing chronic liver disease (CLD) are more likely to have poorer outcomes following COVID-19 infection compared to those without CLD. Co-morbidities such as diabetes, hypertension, obesity, cardiovascular and chronic kidney disease frequently co-exist in individuals living with CLD, and a substantial population may also live with some degree of frailty. The mechanisms of how COVID-19 induces liver injury have been postulated. Hepatorenal syndrome (HRS) is the occurrence of kidney dysfunction in patients with severe CLD/fulminant liver failure in the absence of another identifiable cause, and is usually a marker of severe decompensated liver disease. Select reports of HRS following acute COVID-19 infection have been presented, although the risk factors and pathophysiological mechanisms leading to HRS in COVID-19 infection or following COVID-19 treatment remain largely unestablished due to the relative lack and novelty of published data. Evidence discussing the management of HRS in high-dependency care and intensive care contexts is only emerging. In this article, we provide an overview on the speculative pathophysiological mechanisms of COVID-19 induced HRS and propose strategies for clinical diagnosis and management to optimize outcomes in this scenario.

A low rate of end-stage kidney disease in membranous nephropathy: A single centre study over 2 decades

INTRODUCTION

Membranous nephropathy is the commonest cause of nephrotic syndrome in non-diabetic Caucasian adults over the age of 40 years. Primary membranous nephropathy is limited to the kidneys. Clinical management aims to induce remission, either spontaneously with supportive care, or with immunosuppression. Here, we describe the natural history of this condition in a large tertiary centre in the UK.

METHODS

178 patients with primary membranous nephropathy were identified over 2 decades. We collected data on demographics, baseline laboratory values, treatment received and outcomes including progression to renal replacement therapy and death. Analysis was performed on the whole cohort and specific subgroups. Univariate and multivariate Cox regression was also performed.

RESULTS

Median age was 58.3 years with 63.5% male. Median baseline creatinine was 90μmol/L and urine protein-creatinine ratio 664g/mol. Remission (partial or complete) was achieved in 134 (75.3%), either spontaneous in 60 (33.7%) or after treatment with immunosuppression in 74 (41.6%), and of these 57 (42.5%) relapsed. Progression to renal replacement therapy was seen in 10.1% (much lower than classically reported) with mortality in 29.8%. Amongst the whole cohort, those who went into remission had improved outcomes compared to those who did not go into remission (less progression to renal replacement therapy [4.5% vs 28%] and death [20.1% vs 67%]. Those classified as high-risk (based on parameters including eGFR, proteinuria, serum albumin, PLA2R antibody level, rate of renal function decline) also had worse outcomes than those at low-risk (mortality seen in 52.6% vs 10.8%, p<0.001). The median follow-up period was 59.5 months.

CONCLUSION

We provide a comprehensive epidemiologic analysis of primary membranous nephropathy at a large tertiary UK centre. Only 10.1% progressed to renal replacement therapy. For novelty, the KDIGO risk classification was linked to outcomes, highlighting the utility of this classification system for identifying patients most likely to progress.

The Role of Iron in Calciphylaxis—A Current Review

Calcific uraemic arteriolopathy (CUA), also known as calciphylaxis, is a rare and often fatal condition, frequently diagnosed in end-stage renal disease (ESRD) patients. Although exact pathogenesis remains unclear, iron supplementation is suggested as a potential risk factor. Iron and erythropoietin are the main stay of treatment for anaemia in ESRD patients. Few observational studies support the role of iron in the pathogenesis of calciphylaxis although data from the pivotal trial was not strongly supportive of this argument, i.e., no difference in incidence of calciphylaxis between the low-dose and high-dose iron treatment arms. Elevated levels of vascular cell adhesion molecules in association with iron excess were postulated to the pathogenesis of CUA by causing inflammation and calcification within the microvasculature. In-addition, oxidative stress generated because of iron deposition in cases of systemic inflammation, such as those seen in ESRD, may play a role in vascular calcification. Despite these arguments, a direct correlation between cumulative iron exposure with CUA incidence is not clearly demonstrated in the literature. Consequently, we do not have evidence to recommend iron reduction or cessation in ESRD patients that develop CUA.

Intrinsic Kidney Pathology in Children and Adolescents Following COVID-19 Vaccination: A Systematic Review

Global COVID-19 vaccination programs for children and adolescents have been developed with international clinical trial data confirming COVID-19 mRNA vaccine safety and efficacy for the pediatric population. The impact of COVID-19 vaccination in the kidneys is thought to be explained by a complex immune-mediated relationship between the two, although the pathophysiological mechanisms of how COVID-19 vaccination potentially induces kidney pathology are not presently well known. Whilst intrinsic kidney pathologies following COVID-19 vaccination have been reported in adults, such cases are only being recently reported with greater frequency in children and adolescents. Conforming to the PRISMA checklist, we conducted a systematic review of the current literature to provide an overview on the range of intrinsic kidney pathologies that have been reported following COVID-19 vaccination in children and adolescents. All English language research articles published on or before 30 June 2022 reporting new-onset or relapsed intrinsic kidney pathology in children or adolescents (≤18 years) following COVID-19 vaccination were selected for qualitative analysis. Out of 18 cases from the 13 published articles selected, there were 10 cases of IgA nephropathy (1 case of rapidly progressive glomerulonephritis requiring acute hemodialysis), 5 cases of minimal change disease (MCD), 1 case of concurrent MCD/tubulointerstitial nephritis (TIN) and 2 cases of TIN. There is no indication currently to avoid vaccination, unless specific circumstances exist, as the benefits of COVID-19 vaccination far outweigh its risks. Concluding the findings from our systematic review based on preliminary evidence, potential adverse effects to the kidney from COVID-19 vaccination affects a small number of children and adolescents among the many who have been vaccinated. There remains good reason at present to support vaccination of children and adolescents with a greater morbidity status, such as those living with preexisting chronic kidney disease. Close observation of all children and adolescents receiving COVID-19 vaccination is recommended, particularly in those with preceding intrinsic kidney pathology to identify risks of relapsed disease.

The epidemiology and evolution of IgA nephropathy over two decades: A single centre experience

Background and objectives

IgA nephropathy (IgAN) is the most common glomerulonephritis worldwide, with an incidence of 2.5 per 100,000 population per year. The 10-year risk of progression to end stage kidney disease (ESKD) or halving of eGFR is 26%. Here we aimed to collect a comprehensive dataset of IgAN patients at our centre over 2 decades to provide real world data, describe outcomes and determine the effects of immunosuppression use.

Design, setting, participants and measurements

All patients diagnosed with biopsy-proven IgAN at our centre over 2 decades were identified. After exclusions, the total cohort size was 401. Data relating to (i) baseline demographics, (ii) laboratory and urine results, (iii) histological data, and (iv) outcomes of initiation of renal replacement therapy (RRT) and mortality were collected.

Results

The median age was 45.0 years, with 69.6% male and 57.6% hypertensive; 20.4% received immunosuppression, 29.7% progressed to RRT and 19.7% died, over a median follow up period of 51 months. Baseline eGFR was 46.7ml/min/1.73m² and baseline uPCR was 183mg/mmol. Median rate of eGFR decline was -1.31ml/min/1.73m²/year. Those with a higher MEST-C score had worse outcomes. Immunosuppression use was associated with an increased rate of improvement in proteinuria, but not with a reduction in RRT or mortality. Factors favouring improved outcomes with immunosuppression use included female gender; lower age, blood pressure and T-score; higher eGFR; and ACEi/ARB use.

Conclusions

A variety of clinical and histological factors are important in determining risk of progression in IgAN. Therapeutic interventions, particularly use of immunosuppression, should be individualised and guided by these factors.

Obesity and Chronic Kidney Disease A Current Review

Background

Obesity poses significant challenges to healthcare globally, particularly through its bi-directional relationship with co-morbid metabolic conditions such as type 2 diabetes and hypertension. There is also emerging evidence of an association between obesity and chronic kidney disease (CKD) which is less well characterized.

Methods

A literature search of electronic libraries was conducted to identify and present a narrative review of the interplay between obesity and CKD.

Findings

Obesity may predispose to CKD directly as it is linked to the histopathological finding of obesity-related glomerulopathy and indirectly through its widely recognized complications such as atherosclerosis, hypertension, and type 2 diabetes. The biochemical and endocrine products of adipose tissue contribute to pathophysiological processes such as inflammation, oxidative stress, endothelial dysfunction, and proteinuria. The prevention and management of obesity may prove critical in counteracting both the development and advancement of CKD. Moreover, measures of abdominal adiposity such as waist circumference, are generally associated with worse morbidity and mortality in individuals receiving maintenance hemodialysis.

Conclusion

Obesity is a risk factor for the onset and progression of CKD and should be recognized as a potential target for a preventative public health approach to reduce CKD rates within the general population. Future research should focus on the use of glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter 2 inhibitors in patients with CKD and obesity due to their multi-faceted actions on major outcomes.

Increasing Uptake of COVID-19 Vaccination and Reducing Health Inequalities in Patients on Renal Replacement Therapy-Experience from a Single Tertiary Centre

BACKGROUND

COVID-19 vaccination has changed the landscape of the COVID-19 pandemic; however, decreased uptake due to vaccine hesitancy has been observed, particularly in patients from minority ethnic backgrounds and socially deprived areas. These patient characteristics are common in patients on Renal Replacement Therapy (RRT), a population at extremely high risk of developing serious illness from COVID-19 and who would thus benefit the most from the vaccination programme. We designed a bespoke COVID-19 vaccination programme for our RRT population with the aim of decreasing health inequalities and increasing vaccination uptake.

METHODS

Key interventions included addressing vaccine hesitancy by deploying the respective clinical teams as trusted messengers, prompt eligible patient identification and notification, the deployment of resources to optimise vaccine administration in a manner convenient to patients, and the timely collection and analysis of local safety and efficacy data. First, COVID-19 vaccination data in relation to ethnicity and social deprivation in our RRT population, measured by the multiple deprivation index, were analysed and compared to uptake data in the total regional adult clinically extremely vulnerable (CEV) population in Greater Manchester (GM). Univariate logistic regression analysis was used to explore the factors associated with not receiving a vaccine.

RESULTS

Out of 1156 RRT patients included in this analysis, 96.7% received the first dose of the vaccination compared to 93% in the cohort of CEV patients in the GM. Age, gender, ethnicity, and a lower index of multiple deprivation were not identified as significant risk factors for poor first dose vaccine uptake in our cohort. Vaccine uptake in Asian and Black RRT patients was 94.9% and 92.3%, respectively, compared to 93% and 76.2% for the same ethnic groups in the reference CEV GM. Vaccine uptake was 96.1% for RRT patients in the lowest quartile of the multiple deprivation index, compared to 90.5% in the GM reference population.

CONCLUSION

Bespoke COVID-19 vaccination programmes based on local clinical teams as trusted messengers can improve negative attitudes towards vaccination and reduce health inequalities.

MO412: Impact of Body Mass Index on Mortality and End–Stage Kidney Disease in Patients With Non-Dialysis Dependent Chronic Kidney Disease

BACKGROUND AND AIMS

Obesity is a major global problem affecting more than 1.9 billion adults [1]. The aetiological factors of obesity are complex and consist of genetic, social and environmental elements. Obesity can lead to chronic kidney disease (CKD) via both direct and indirect pathways. However, the effect of obesity on the progression of CKD remains unclear. This study aimed to investigate the impact of higher body mass index (BMI) on clinical outcomes in a large UK cohort of patients with non-dialysis dependent (NDD)-CKD.

METHOD

The Salford Kidney Study is a longitudinal prospective cohort of more than 3000 patients with NDD-CKD. All patients with available BMI at baseline from October 2002 to December 2016 were included in this study. Patients were grouped according to their BMI into underweight [(BMI &lt; 18.5 kg/m2), n = 35], healthy weight [(BMI 18.5–24.9 kg/m2), n = 628], overweight [(BMI 25–29.9 kg/m2), n = 860] and obese [(BMI &gt; 30 kg/m2), n = 897]. Cox-regression analysis was performed to study the strength of association between BMI groups and major clinical outcomes [all-cause mortality, end-stage kidney disease (ESKD) and annual rate of progression of CKD (delta eGFR)] by using the healthy weight BMI group as a reference. The outcomes were also analysed in a 1:1 propensity score-matched analysis between patients in the healthy weight and obese groups (414 in each).

RESULTS

A total of 2420 patients with a median follow-up of 44.3 months were available for analysis. The median age of the cohort was 67 years and 58% were male. The prevalence of hypertension and diabetes increased with a higher BMI (84.0% and 18.8% in healthy weight, 91.7% and 31.0% in overweight and 94.2% and 46.8% in the obese groups, respectively). There was no significant difference in the baseline eGFR between the groups with a median of 29.3 mL/min/1.73 m2. There was an inverse association between a higher BMI and all-cause mortality [obese versus healthy weight: hazard ratio (HR): 0.88; 95% confidence interval (CI): 0.81–0.96; P = 0.004] but there was no association observed with ESKD (HR 0.96; 95% CI: 0.87–1.06; P = 0.422). The delta eGFR was not significantly different between the different BMI groups (Table 1). A similar observation with all-cause mortality being better in the obese group was noted in the propensity-matched analysis (HR:0.88; CI:0.81–0.96; P = 0.004) (Table 2).

CONCLUSION

In our large cohort of patients, a higher BMI was seen to be protective against all-cause mortality. Furthermore, the annual rate of decline in eGFR was similar among the BMI groups. Patients with normal BMI had significantly higher all-cause mortality compared with the obese group.

MO699: Investigating Longer Term Antibody Response Following Covid-19 Vaccination in Patients Receiving Peritoneal Dialysis—a Single-Center Observational Study

BACKGROUND AND AIMS

Individuals with end-stage kidney disease (ESKD) have a greater susceptibility towards coronavirus disease 2019 (COVID-19) infection compared to those without chronic kidney disease or ESKD, and these patients are more vulnerable to poor clinical outcomes. The introduction of COVID-19 vaccination programs displayed efficacy to improving clinical outcomes. A study based in the UK reported excellent humoral responses to the Pfizer BNT162b2 vaccine, but suboptimal responses to the Oxford AstraZeneca ChAdOx1-nCoV-19(AZD1222) vaccine amongst hemodialysis patients. High rate of humoral responses to two doses of the COVID-19 vaccination has been reported within small cohorts of peritoneal dialysis (PD) patients 3 to 8 weeks post vaccination, whilst one study confirmed maintenance of significant humoral responses 6 months post vaccination with the Pfizer BNT162b2 vaccine. Our study aimed at evaluating longer-term antibody responses—6 months after a two-dose regimen of the Pfizer BNT162b2 and Oxford AstraZeneca ChAdOx1-nCoV-19 (AZD1222) vaccines in patients receiving PD.

METHOD

This is a single-center observational study conducted for PD patients who were offered both doses of the COVID-19 vaccine [either Pfizer BNT162b2 or Oxford AstraZeneca ChAdOx1-nCoV-19(AZD1222)] since universal introduction of the vaccination program in our local area in December 2020. COVID-19 antibody testing was performed using the Siemens’ immunoassay targeting the spike protein S1 RBD (an index ≥ 1.0 was deemed as a positive result) between October and November 2021. Demographic and baseline clinical data were collected for each patient, and analysis focused on comparing the characteristics between PD patients with positive and negative COVID-19 antibody statuses. Statistical analysis was performed using SPSS version 24.

RESULTS

Eighty-six patients were included in this study. The median age was 62 years (47–71) with a predominance of males (61.6%) and Caucasian ethnicity (75.6%). The majority of patients have hypertension (84.8%) with 38% having a history of cardiovascular disease and 34% being diabetic. Ten patients (11.6%) previously received a kidney transplant with 7 patients (8.2%) currently on immunosuppressive treatment, and 15 patients (17.4%) previously receiving such treatments. A total of 81 patients received both doses of the COVID-19 vaccine, of which 57 (70.4%) received Pfizer BNT162b2, 16 (19.7%) received Oxford AstraZeneca ChAdOx1-nCoV-19 (AZD1222) and the type of vaccine was unknown in 8 patients (9.9%). A total of 72 patients were COVID-19 antibody tested between October and November 2021 in which 68 (94.4%) had a positive antibody and 4 (5.6%) had a negative antibody test. The median time between first dose of the COVID-19 vaccination and antibody testing was 9 (8.6–9.5) months and the median time between second dose of the COVID-19 vaccination and antibody testing was 6.3 (5.8–6.7) months. Comparing the demographic and clinical characteristics between patients with positive and negative antibodies, a higher proportion of patients with history of receiving immunosuppression (currently or previously; P = 0.004) had a negative antibody status despite receiving two doses of COVID-19 vaccination. There were no further significant differences observed. Full study results are presented in Tables 1 and 2.

CONCLUSION

In our cohort of PD patients, detectable humoral response to COVID-19 vaccination was sustained 6 months following vaccination irrespective of the type of vaccination received. A higher proportion of patients with a history of receiving immunosuppression (current or past) had a poor antibody response following COVID-19 vaccinations, highlighting the importance of considering focused COVID-19 vaccination strategies in the context of immunosuppression.

MO240: The Evolution and Epidemiology of Membranous Nephropathy at a Single Centre Over Two Decades

BACKGROUND AND AIMS

Membranous nephropathy (MN) commonly presents with nephrotic syndrome and carries significant risk of progression to end-stage kidney disease (ESKD) (33% without treatment, 10%–20% with). Patients may spontaneously remit (up to 40%), but are also at risk of relapse. A total of 80% of cases are primary (kidney-specific) and the majority of these are associated with antibodies to the M-type phospholipase A2 receptor (anti-PLA2R) or thrombospondin type 1 domain containing 7A antibodies (THS7DA). Treatment ranges from supportive care with renin–angiotensin system (RAS) blockade through to immunosuppression. Here we assessed the epidemiology of MN over 20 years at our centre (Salford Royal Hospital, UK) with particular reference to treatment administered and key clinical outcomes.

METHOD

A total of 238 patients with kidney biopsy-proven MN were identified from the local database between January 2000 and December 2020. Twenty-one were excluded (see Fig. 1) resulting in a total of 217 patients in whom demographic data, co-morbidities, remission and relapse rates, baseline laboratory values, treatment given, and outcomes were collected. Analyses compared effects of (i) immunosuppressed versus non-immunosuppressed, (ii) effect of modified Ponticelli versus other forms of immunosuppression and (iii) rates of remission. Univariate and multivariate cox regression determined factors that were associated with increased risk of renal replacement therapy (RRT) or death.

RESULTS

A total of 63.6% of the cohort were male, 88% Caucasian, 10.1% diabetic, 50.2% hypertensive and 15.2% had coexisting cardiovascular disease (Table 1). A total of 82.0% had primary MN. Median baseline eGFR was 72.7 mL/min/1.73 m2 and median baseline uPCR was 664 g/mol. A total of 157 patients (72.4%) went into remission (either spontaneous—75 (47.8%) or with treatment—85 (52.2%)), and of these 41.4% subsequently relapsed. A total of 89.4% received RAS blockade and 48.8% received immunosuppression. The median follow-up period was 56 months; 9.7% progressed to ESKD and 32.3% died.

Patients who received immunosuppression had significantly more proteinuria than those who did not (765 g/mol versus 514 g/mol, P ≤ 0.001), were more likely to relapse (53.7% versus 28.0%, p ≤0.001) and were more likely to require RRT (15.1% versus 4.9%, P = .028). Those who received modified Ponticelli were less likely to relapse than those who received other forms of immunosuppression (34% versus 46%, P = .019), less likely to require RRT (3% versus 22%, P = .018) and less likely to die (11% versus 38%).

Multivariate cox regression showed that pre-existing cardiovascular disease was a risk factor for death (HR 2.47, P &lt; .001) and higher baseline eGFR and use of RAS blockade was associated with reduced risk of death (HR 0.98, P &lt; .001 and HR 0.34, P = .012, respectively).

CONCLUSION

Despite advances in knowledge of underlying pathogenesis and increased treatment options, MN continues to pose a significant risk of progression to ESKD and death. This real-world study suggests that immunosuppression with modified Ponticelli is associated with lower rates of progressive CKD compared with MMF and calcineurin-inhibitor based therapy. Whilst many patients respond to treatment and can achieve remission, a significant proportion of these subsequently relapse. Identifying these patients early with judicial use of appropriate immunosuppression is key.

MO987: Risk Predictors and Impact of Post-Transplant Cardiovascular Disease in A 20-Year Cohort of Kidney Transplant Recipients

BACKGROUND AND AIMS

Although improvement in histocompatibility matching, immunosuppressive therapy and antimicrobial treatment have led to improved long-term allograft survival, cardiovascular diseases (CVD) remain the major cause of morbidity and mortality in kidney transplant recipients (KTR). In addition to the accumulated risks due to chronic kidney disease and dialysis, kidney transplantation conveys its own unique risk factors for CVD. These include the metabolic effects of immunosuppressive treatments such as post-transplant hyperglycaemia, dyslipidaemia and hypertension as well as the effects of suboptimal kidney function including volume overload, anaemia, mineral bone disease and left ventricular hypertrophy. The predictors of cardiovascular diseases in KTR, however, have not been clearly defined.

This study aimed to first ascertain the incidence of post-transplant CVD in those KTR without a prior confirmed history of CVD, then identify the predictors of CVD transplant associated CVD risk factors and finally evaluate the impact of CVD on graft and patient survival in this era of modern immunosuppressive medications.

METHOD

We evaluated 962 KTR transplanted between 2000 and 2020 and followed in a single centre. About 328 KTR with a history of pre transplant CVD were excluded. CVD was defined as a composite of Ischaemic heart disease, myocardial infarction, heart failure, stroke or peripheral vascular disease. Logistic regression analyses were performed to identify the risk predictors of post-transplant CVD. Kaplan–Meier plots and multivariate Cox proportional hazards regression analysis were used to identify and characterize predictors of dialysis free survival.

RESULTS

Among 634 KTR included in the analysis (mean age: 45 ± 15 years), CVD was reported in 101 KTR (16%) during a median follow-up of 95.9 months. About 274(43%) were females, 531(84%) were Caucasians. KTR with post-transplant CVD were likely to be older (50 ± 13 versus 44 ± 15 years; P  &lt; 0.001), had spent more time on dialysis [median (IQR) 21 (1–51) versus 11 (0–3) months; P = 0.004] and received cyclosporin maintenance (18% versus 7%; P = 0.01). Incidence of post-transplant CVD was independently predicted by older age [OR: 1.40 (1.15–1.70: P = 0.001)], tacrolimus therapy [OR: 0.81 (0.71–0.93), P = 0.002], mean haemoglobin concentration [OR: 0.86 (0.75–1.00), P = 0.049] and average C-reactive protein (CRP) level [OR: 1.13 (1.02–1.25), P = 0.02] (Figure 1). The median dialysis free survival was significantly lower in KTR who developed post-transplant CVD (14.7 versus 20 years, P = 0.009).

In the multivariate Cox regression analysis, the factors associated with worse dialysis free survival in our cohort (survival with a functioning graft) were older age at transplantation [hazard ratio (HR): 1.03; P  &lt; 0.001), a history of post-transplant CVD (HR: 1.68; P = 0.006), higher post-transplant parathormone levels (HR: 1.02; P &lt; 0.001), higher mean urine protein creatinine ratio (uPCR) (HR: 1.003: P &lt; 0.001), a greater annual rise in uPCR (HR: 1.002; P  &lt; 0.001) and a history of acute rejection (HR: 1.56; P = 0.03). Statin treatment was associated with better dialysis free survival outcome (HR: 0.60; P = 0.01).

CONCLUSION

The incidence of post-transplant CVD in KTR with no history of pre-transplant CVD was 16%. Age at transplantation and average CRP were independent predictors of post-transplant CVD whereas treatment with Tacrolimus was associated with a lower risk of CVD. Statin therapy was associated with better dialysis free survival whereas a higher PTH was linked to poor survival. It was interesting to note that diabetes was not independently associated with the risk and outcome of post-transplant CVD in our cohort.

MO986: Incidence And Predictors of Post-Transplant De-Novo Malignancy: A Single-Centre Retrospective Cohort Study

BACKGROUND AND AIMS

Improvement in short to medium term kidney transplant outcomes and increasingly successful transplantation older patients have led to increasing occurrence of long-term complications of transplantation. Amongst these complications, cancer has become an important cause of mortality following kidney transplantation necessitating the need to better understand the risk factors for the development of de novo malignancy.

This study aimed to evaluate the prevalence and the risk factors of de-novo malignancy in a single UK tertiary nephrology centre.

METHOD

This retrospective cohort study included all kidney transplant recipients (KTR) at our centre, that underwent kidney transplantation between 2000 and 2020 and followed up at our centre. The incidence and types of malignancies excluding non-melanoma skin cancer (NMSC) were analysed. The characteristics of KTR with post-transplant malignancy (excluding NMSC) were compared to those without post-transplant malignancy. Univariate and multivariate logistic regression analyses were conducted to identify the risk predictors of post-transplant cancers. Graft survival and dialysis free survival and death with functioning graft were assessed using Kaplan-Mayer analysis and Cox-regression.

RESULTS

We analysed the records of 962 KTR (mean age = 47 ± 15 years), followed-up over a median period of 16 years. About 365 (38%) were women, and 783(81%) were Caucasian. 268(32%) had a pre-emptive transplant and 277(29%) had a live donor transplant.

Post-transplant malignancy was diagnosed in 84(9%) KTR. KTR with post-transplant cancers were likely to be older (53 ± 14 versus 47 ± 15 years; P = 0.004), on long-term steroid maintenance therapy (64% versus 47%; P = 0.004) and have a history of post-transplant DNA virus infection (40% versus 29%; P = 0.029). Conversely, those with cancers are less likely to be on mycophenolic acid (MPA) therapy (65% versus 78%; P = 0.023). The most common cancers diagnosed were genitourinary cancers (27%) followed by gastrointestinal (24%) and haematological cancers (24%). Respiratory, neurological and others accounted for 10%, 2.4% and 11% of the diagnosed cancers.

In multivariate logistic regression analysis, increasing risk of post-transplant cancer was associated with older age at transplantation [OR: 1.81 (1.3–2.5; P &lt; 0.001)], male gender [OR 2.3 (1.3–8.3; P = 0.01)], corticosteroid maintenance [OR 2.3 (1.1–5.2: P = 0.03)], Tobacco smoking [OR: 3.33 (1.2–8.9: P = 0.01)], higher Baseline estimated glomerular filtration rate (eGFR), [OR: 1.2 (1.0–1.4; P = 0.02)], and post-transplant DNA-virus infection [OR: 2.3 (1.0–5.1; P = 0.02)] (Figure 1).

There was no difference in the death censored graft survival between the cancer group and the no-cancer group (log-rank, P = 0.51). However, those with cancers had a significantly worse dialysis free survival (log-rank; P = 0.04) and significantly higher death with functioning graft (log-rank; P = 0.02). In the multivariate Cox regression, adjusted for several confounders, dialysis free survival did not differ significantly between the cancer and non-cancer groups (adjusted hazard ratio; aHR: 1.6; P = 0.10). However, age (aHR: 1.16; P = 0.01), male gender (aHR: 1.6; P = 0.01), cardiovascular disease (CVD) (HR: 1.6; P = 0.01) and acute rejection (aHR: 1.7; P = 0.02) were predictors of lower dialysis free survival.

CONCLUSION

Post-transplant cancers occurred in 9% of our cohort during a median follow-up of 16years. Genitourinary cancers were the most commonly occurring cancers. Older age, male gender, corticosteroid maintenance, smoking and DNA virus infections were the risk factors of malignancy. There was no significant difference in dialysis free survival between the cancer group and the no cancer groups. Lower dialysis free survival was predicted by age, gender, CVD and a history of acute rejection.

Erythropoietin-Stimulating Agent Hyporesponsiveness in Patients Living with Chronic Kidney Disease

BACKGROUND

Erythropoietin-stimulating agent (ESA) hyporesponsiveness is commonly observed in patients with anemia secondary to chronic kidney disease (CKD). Because of its complexity, a global consensus on how we should define ESA hyporesponsiveness remains unavailable. The reported prevalence and demographic information on ESA hyporesponsiveness within the CKD population are variable with no consensus definition.

SUMMARY

ESA hyporesponsiveness is defined as having no increase in hemoglobin concentration from baseline after the first month of treatment on appropriate weight-based dosing. The important factors associated with ESA hyporesponsiveness include absolute or functional iron deficiency, inflammation, and uremia. Hepcidin has been demonstrated to play an important role in this process. Mineral bone disease secondary to CKD and non-iron malnutrition among other factors are also associated with ESA hyporesponsiveness. There is continued debate toward determining a gold-standard treatment pathway to manage ESA hyporesponsiveness. The development of hypoxia-inducing factor-stabilizers brings new insights and opportunities in the management of ESA hyporesponsiveness.

KEY MESSAGE

Management of ESA hyporesponsiveness involves a comprehensive multidisciplinary team approach to address its risk factors. The progression of basic and clinical research on identifying risk factors and management of ESA hyporesponsiveness brings greater hope on finding solutions to eventually tackling one of the most difficult problems in the topic of anemia in CKD.

Does previous stroke modify the relationship between inflammatory biomarkers and clinical endpoints in CKD patients?

Background

Chronic kidney disease (CKD) is an independent risk factor for stroke. Stroke is also an independent risk factor for worse CKD outcomes and inflammation may contribute to this bidirectional relationship. This study aims to investigate inflammatory biomarkers in patients with non-dialysis CKD (ND-CKD) with and without stroke.

Methods

A propensity matched sample from > 3000 Salford Kidney Study (SKS) patients, differentiated by previous stroke at study recruitment, had stored plasma analyzed for interleukin- 6 (IL-6), Von Willebrand Factor (VWF) and C-reactive protein (CRP). Multivariable cox regression analysis investigated associations between inflammation and death, end-stage renal disease (ESRD) and future non-fatal cardiovascular events (NFCVE).

Results

A total of 157 previous stroke patients were compared against 162 non-stroke patients. There were no significant differences in inflammatory biomarkers between the two groups. Previous stroke was associated with greater mortality risk, hazard ratio (HR) (95% CI) was 1.45 (1.07–1.97). Higher inflammatory biomarker concentrations were independently associated with death but not ESRD or NFCVE in the total population. For each 1 standard deviation (SD) increase in log IL-6, VWF and CRP, the HR for all-cause mortality were 1.35 (1.10–1.70), 1.26 (1.05–1.51) and 1.34 (1.12–1.61), respectively. CRP retained its independent association (HR 1.47 (1.15–1.87)) with death in the stroke population.

Conclusion

Previous stroke is an important determinant of mortality. However, the adverse combination of stroke and ND-CKD does not seem to be driven by higher levels of inflammation detected after the stroke event. Biomarkers of inflammation were associated with worse outcome in both stroke and non-stroke ND-CKD patients.

Trial registration

15/NW/0818.

What you see may not be what you get! Simulate towards effective planning of pediatric intensive care unit

AIMS AND OBJECTIVES

This study aimed to describe the application of low-cost inter-professional simulation over 4 phases in identifying structural and design issues, latent safety threats as well as test systems, processes, including facilitated team training during the design of a new pediatric intensive care unit (PICU).

MATERIALS AND METHODS

The four-phase inter-professional simulation sessions involving clinical and non-clinical teams were conducted over a 3-month period in a corporate hospital during the designing of a new PICU. Low-cost resources, such as floor tapes, low-tech manikins, reused sterilized consumables, and actual patient beds and equipment, were used for the in situ simulation sessions. A plus-delta method of debriefing was done, and changes agreed on consensus were implemented after each simulated session.

RESULTS

There were 10 simulation sessions conducted over 4 phases during the 3-month period of designing the PICU. The participants included 10 doctors from PICU and adult critical care, 25 critical care nurses, 12 members from the project team, and 2 hospital administrators in various combinations. The first phase led to the re-design of workspace and clinical areas for better space utilization. The second phase required further revision to facilitate better mobility and facilities. In the third phase, the number of beds was reduced to 6 beds following the simulated drills involving the actual placement of patient cots and equipment. The fourth phase had thematic 5 simulated exercises involving the newly recruited clinical teams that enabled the identification of systems and process issues. Cognitive aids and video orientation of the setup, team training, and human factors training were addressed, and the unit was open for patient care in a week.

CONCLUSION

A phased inter-professional simulation exercise with low-cost resources can enable the identification of structural challenges, design issues, latent safety threats, test systems, processes, patient flow, and facilitated team training during the design of a new PICU. Further studies are needed to understand the generalization of the study findings into designing PICU.

A Quality Improvement Project to Minimize COVID-19 Infections in Patients Receiving Haemodialysis and the Role of Routine Surveillance Using Nose and Throat Swabs for SARS-CoV-2 rRT-PCR and Serum Antibody Testing

Background

Patients receiving in-centre haemodialysis (ICHD) are highly vulnerable to COVID-19.

Objective

We created a quality improvement (QI) project aimed to eliminate outbreaks of COVID-19 in haemodialysis units and evaluated the utility of surveillance rRT-PCR test and SARS-CoV-2 serum antibodies for prompt identification of patients infected with COVID-19.

Methods

A multifaceted QI programme including a bundle of infection prevention control (IPC) measures was implemented across 5 ICHD units following the first wave of the pandemic in June 2020. Primary outcomes evaluated before and after QI implementation were incidence of outbreaks and severe COVID-19 illness defined as COVID-19-related death or hospitalization. Secondary outcomes included the proportion of patients identified in the pre-symptomatic/asymptomatic phase on surveillance rRT-PCR screening and the incidence and longevity of SARS-CoV-2 antibody response.

Results

Following the implementation of the QI project, there were no further outbreaks. Pre- and post-implementation comparison showed a significant reduction in COVID-19-related mortality and hospitalization (26 vs. 13 events, respectively, p < 0.001). Surveillance rRT-PCR screening identified 39 asymptomatic or pre-symptomatic cases out of a total of 59 rRT-PCR-positive patients (39/59, 66%). SARS-CoV-2 antibody levels were detected in 72/74 (97%) rRT-PCR-positive patients. Amongst rRT-PCR-positive patients diagnosed before August 2020, 96% had detectable antibodies until January 2021 (days from the rRT-PCR test to last antibody testing, 245–280).

Conclusions

Systematic implementation of a bundle of IPC measures using QI methodology and surveillance rRT-PCR eliminated outbreaks in HD facilities. Most HD patients mount and sustain antibody response to COVID-19 for over 8 months.

Native and transplant kidney histopathological manifestations in association with COVID-19 infection: A systematic review

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can result in clinically significant multi-system disease including involvement in the kidney. The underlying histopathological processes were unknown at the start of the pandemic. As case reports and series have been published describing the underlying renal histopathology from kidney biopsies, we have started to gain an insight into the renal manifestations of this novel disease.

AIM

To provide an overview of the current literature on the renal histopathological features and mechanistic insights described in association with coronavirus disease 2019 (COVID-19) infection.

METHODS

A systematic review was performed by conducting a literature search in the following websites-‘PubMed’, ‘Web of Science’, ‘Embase’ and ‘Medline-ProQuest’ with the following search terms-“COVID-19 AND kidney biopsy”, “COVID-19 AND renal biopsy”, “SARS-CoV-2 AND kidney biopsy” and “SARS-CoV-2 AND renal biopsy”. We have included published data up until February 15, 2021, which includes kidney biopsies (native, transplant and postmortem) from patients with COVID-19. Data on clinical presentation, histopathological features, management and outcome was extracted from the reported studies.

RESULTS

The total number of biopsies reported on here is 288, of which 189 are postmortem, 84 native and 15 transplants. The results are varied and show underlying pathologies ranging from collapsing glomerulopathy and acute tubular injury (ATI) to anti-nuclear cytoplasmic antibody associated vasculitis and pigment nephropathy. There was variation in the specific treatment used for the various renal conditions, which included steroids, hydroxychloroquine, eculizumab, convalescent plasma, rituximab, anakinra, cyclophosphamide and renal replacement therapy, amongst others. The pathological process which occurs in the kidney following COVID-19 infection and leads to the described biopsy findings has been hypothesized in some conditions but not others (for example, sepsis related hypoperfusion for ATI). It is important to note that this represents a very small minority of the total number of cases of COVID-19 related kidney disease, and as such there may be inherent selection bias in the results described. Further work will be required to determine the pathogenetic link, if any, between COVID-19 and the other renal pathologies.

CONCLUSION

This report has clinical relevance as certain renal pathologies have specific management, with the implication that kidney biopsy in the setting of renal disease and COVID-19 should be an early consideration, dependent upon the clinical presentation.

Etanercept-Induced Anti-Glomerular Basement Membrane Disease

Anti-glomerular basement membrane (anti-GBM) disease is a rare form of small-vessel vasculitis that typically causes rapidly progressive glomerulonephritis with or without alveolar haemorrhage. Previously, there has only been one reported case of tumour necrosis factor-α (TNF-α) antagonist-induced anti-GBM disease. Here, we describe the first reported case of etanercept-induced anti-GBM disease. A 55-year-old Caucasian man was referred to our tertiary specialist renal centre with a history of painless macroscopic haematuria. The patient has been receiving weekly etanercept injections over the past 12 months for psoriatic arthropathy. The serum immunology panel results highlighted a significantly raised anti-GBM titre (370.1 U). Etanercept was stopped, and the patient was empirically commenced on pulsed methylprednisolone, cyclophosphamide, and plasma exchange. A renal biopsy showed crescentic glomerulonephritis. Few days after admission, he tested positive for coronavirus disease 2019 (COVID-19), and a decision was made to withhold cyclophosphamide. There was further decline in renal function with hyperkalaemia for which he received 2 sessions of haemodialysis. He was restarted on cyclophosphamide upon discharge. The patient was switched to rituximab treatment afterwards as he developed leucopenia 2 weeks following the commencement of cyclophosphamide. The serum creatinine level continued to improve and remained dialysis-independent. In conclusion, with the increased use of etanercept and other TNF-α antagonists, the prescribing clinician must be aware of the rare but life-threatening drug-induced vasculitis. We recommend careful monitoring of renal indices with the use of this class of medications.

New-Onset and Relapsed Kidney Histopathology Following COVID-19 Vaccination: A Systematic Review

INTRODUCTION

The introduction of COVID-19 vaccination programs has become an integral part of the major strategy to reduce COVID-19 numbers worldwide. New-onset and relapsed kidney histopathology have been reported following COVID-19 vaccination, sparking debate on whether there are causal associations. How these vaccines achieve an immune response to COVID-19 and the mechanism that this triggers kidney pathology remains unestablished. We describe the results of a systematic review for new-onset and relapsed kidney histopathology following COVID-19 vaccination.

METHODS

A systematic literature search of published data up until 31 August 2021 was completed through the Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) guideline. Research articles reporting new onset or relapsed kidney histopathology in adult patients (>18 years) following COVID-19 vaccination were included for qualitative review. Only full-text articles published in the English language were selected for review.

RESULTS

Forty-eight cases from thirty-six articles were included in the qualitative synthesis of this systematic review. Minimal change disease (19 cases) was the most frequent pathology observed, followed by IgA nephropathy (14 cases) and vasculitis (10 cases). Other cases include relapse of membranous nephropathy, acute rejection of kidney transplant, relapse of IgG4 nephritis, new-onset renal thrombotic microangiopathy, and scleroderma renal crisis following COVID-19 vaccination. There was no mortality reported in any of the included cases. Patients in all but one case largely recovered and did not require long-term renal replacement therapy.

CONCLUSION

This systematic review provides insight into the relationship between various kidney pathologies that may have followed COVID-19 vaccination. Despite these reported cases, the protective benefits offered by COVID-19 vaccination far outweigh its risks. It would be recommended to consider early biopsy to identify histopathology amongst patients presenting with symptoms relating to new-onset kidney disease following vaccination and to monitor symptoms for those with potential relapsed disease.

Longitudinal change in c-terminal fibroblast growth factor 23 and outcomes in patients with advanced chronic kidney disease

BACKGROUND

Fibroblast growth factor23 (FGF23) is elevated in CKD and has been associated with outcomes such as death, cardiovascular (CV) events and progression to Renal Replacement therapy (RRT). The majority of studies have been unable to account for change in FGF23 over time and those which have demonstrate conflicting results. We performed a survival analysis looking at change in c-terminal FGF23 (cFGF23) over time to assess the relative contribution of cFGF23 to these outcomes.

METHODS

We measured cFGF23 on plasma samples from 388 patients with CKD 3-5 who had serial measurements of cFGF23, with a mean of 4.2 samples per individual. We used linear regression analysis to assess the annual rate of change in cFGF23 and assessed the relationship between time-varying cFGF23 and the outcomes in a cox-regression analysis.

RESULTS

Across our population, median baseline eGFR was 32.3mls/min/1.73m², median baseline cFGF23 was 162 relative units/ml (RU/ml) (IQR 101-244 RU/mL). Over 70 months (IQR 53-97) median follow-up, 76 (19.6%) patients progressed to RRT, 86 (22.2%) died, and 52 (13.4%) suffered a major non-fatal CV event. On multivariate analysis, longitudinal change in cFGF23 was significantly associated with risk for death and progression to RRT but not non-fatal cardiovascular events.

CONCLUSION

In our study, increasing cFGF23 was significantly associated with risk for death and RRT.

MO733RISK FACTORS FOR INFECTIVE ENDOCARDITIS IN PATIENTS RECEIVING HAEMODIALYSIS- A PROPENSITY MATCHED COHORT STUDY

Background and Aims

Infective endocarditis (IE) is a serious infective complication that usually results in prolonged hospitalisation and is associated with high morbidity and mortality. It is sometimes difficult to promptly diagnose infective endocarditis when a patient receiving hemodialysis presents with signs and symptoms of bacteremia, a delay which can lead to worse outcomes. In this study, we aimed to identify the risk factors that can predict infective endocarditis in haemodialysis patients with bacteremia.

Method

This retrospective observational study was conducted on all patients diagnosed with infective endocarditis (IE) and receiving maintenance hemodialysis between 2005 and 2018 in Salford Royal Hospital and its satellite dialysis units (catchment population of 1.5 million). The IE patients were propensity score matched in a 1:2 ratio with similar hemodialysis patients without IE but with bacteremia between 2011 and 2015. Propensity scores were generated by using binary logistic regression analysis incorporating age, gender, diabetes status, and dialysis vintage as variables. Logistic regression analysis was used to predict the risk factors associated with developing IE. Statistics were performed using SPSS version-24.

Results

We had a sample of 105 patients (35 IE vs 70 bacteremia). The median age of the patients was 65 years with a predominance of males (60%). 43% were diabetic, 11.5% were receiving immunosuppression and 72% had a catheter for dialysis access. IE patients had higher peak C-reactive protein (CRP) during admission compared to patients with bacteremia and no IE (253 mg/l vs 152 mg/l, p=0.001). Patients who developed IE had a longer duration of dialysis catheter use than the bacteremia group (150 vs 19 days; p&lt;0.001) (table 1). There was no significant difference between causative microorganisms in both groups. Staphylococcus aureus caused most cases (54% in IE and 47% in bacteremia). Our study showed clearly that patients who had IE had longer hospital stay (45 vs 18 days, p=0.001) with a far higher 30-day mortality rate (54.3% vs 17.1%, p&lt;0.001). Logistic regression analysis showed previous valvular heart diseases (OR: 20.1; p&lt;0.001), a higher peak CRP (OR:1.01; p=0.001), and a longer duration of catheter use (OR: 1.01; p=0.035) as significant predictors for infective endocarditis (table 2).

Conclusion

Bacteremia in patients receiving hemodialysis through a catheter as access should be actively investigated with a high index of suspicion for IE particularly those having valvular heart diseases, hypertension, higher peak CRP, and those with a longer duration of dialysis catheter usage. Work up may need to include invasive investigations such as transesophageal echocardiogram to confirm or reliably rule out this devastating condition.

MO287REAL WORLD COMPARISON OF THE PREDICTIVE UTILITY OF INTERNATIONAL IGA RISK PREDICTION SCORE AND KIDNEY FAILURE RISK EQUATION IN IGA NEPHROPATHY PATIENTS

Background and Aims

IgA nephropathy is the most prevalent cause of glomerular disease worldwide. The international IgA risk prediction (IgAN) score is a well validated tool to predict the risk of 50% decline in eGFR or end stage renal disease (ESRD) at five years after biopsy in patients with IgA nephropathy. Also, the four variable kidney failure risk equation (KFRE) is another validated tool used to predict the two- and five-year risk of progression to ESRD of all cause chronic kidney disease (CKD 3-5).

Our aim is to compare the predictive utility of IgAN score and the KFRE in a real-world cohort of Caucasian patients with long-term follow-up data.

Method

All available patients with biopsy-proven IgA nephropathy in our centre between January 2001 and December 2013 were included in this observational study. Baseline (biopsy date) data relevant to the scores including demographics, laboratory and the histopathological features were collated at the time of biopsy. Follow up data on renal functions and renal outcome (50% decline in eGFR or reaching ESRD) were collected until an arbitrary end date 31/12/2018.

Results

We had a total of 115 patients recorded over this 13-year period. The median age of our cohort at time of biopsy was 41 years. Men represented 71% of the cohort. At baseline 84% were hypertensive and 11% diabetic. 77% were on a renin-angiotensin blocker, with 53% being on a statin. Out of the 115 patients, 74 were eligible to undergo analysis. The percentage risk of reaching the endpoint (50% decline in eGFR or reaching ESRD) was calculated at 2 years and 5 years for all patients. These results can be seen in table 1 and 2. At 2 years, 7 patients had reached the endpoint: 2 patients had a &gt;50% decline in eGFR, 3 patients received RRT and 2 patients underwent transplantation. At 5 years, 14 patients had reached the endpoint: 3 patients had a &gt;50% decline in eGFR, 6 patients received RRT and 5 underwent transplantation.

Conclusion

Our data suggests that the KRFE tool underpredicts the risk of reaching endpoint, compared to the IgAN. Our study has helped to compare the two tools, but further statistical validation is required using a larger cohort.

MO306IGA NEPHROPATHY: A 20 YEAR RETROSPECTIVE SINGLE CENTRE EXPERIENCE

Background and Aims

IgA nephropathy is the most common glomerulonephritis worldwide. The clinical course is heterogeneous and not always easy to predict. As such, determining which patients to treat with immunosuppression has been the cause of much debate. Over recent years there has been a focus on risk prediction to help with treatment decisions (such as the widely validated International IgA Risk Prediction Tool). Here, we present a 20 year retrospective study from a single centre with the following aims: to describe the epidemiology of our cohort, to assess outcomes (such as progression to ESKD requiring RRT, mortality), and to determine if treatment choices have changed over time.

Method

We collected all cases of IgA nephropathy from our biopsy database between January 2020 and December 2019. This totalled 525 biopsies. Of these, a number were excluded from analysis, including transplant biopsies and repeat biopsies in the same patient. After exclusion, the original 525 biopsies were narrowed down to 452 patients for analysis. We collected demographic data for each patient, along with creatinine and proteinuria values over time, MEST-C scores, progression to ESKD, mortality, use of RAAS blockade and immunosuppressants. Initial analysis was performed using Excel. We plan to perform further multivariate Cox regression analysis to determine if there are associations with progression to ESKD such as degree of proteinuria, MEST-C scores and immunosuppression treatment.

Results

We identified 452 patients with biopsy confirmed IgA nephropathy at our centre between January 2000 and December 2019. 138 (30.5%) were female and 314 (69.4%) were male. The average age at time of biopsy was 45.7 years. Mortality over this period was 19.2% (87 patients). 126 (27.9%) progressed to ESKD requiring RRT, 6 (1.3%) required temporary dialysis whilst 313 (69.2%) did not require RRT. With regards to treatment, 329 (72.8%) were treated with RAAS blockade in comparison to 85 (18.8%) who were not (in 38 patients this was unclear). No immunosuppression was used in 349 (77.2%), whilst a combination of prednisolone; IV cyclophosphamide and prednisolone; and MMF and prednisolone was used in 97 (21.5%).

Conclusion

We present here a large single centre dataset of IgA nephropathy patients over a 20 year period. We show that there remains a significant risk of progression to ESKD over time. It is important to identify those patients most at risk of progression early on in their disease course so that optimal treatment can be initiated. Further analysis of this dataset will allow us to assess whether treatment strategies in recent years has had a beneficial effect on outcomes, and also to assess the correlation between MEST-C scores and treatment decisions.

MO090TRANSPLANT KIDNEY BIOPSY FINDINGS IN COVID-19: A SYSTEMATIC REVIEW

Background and Aims

Patients with transplanted kidneys are more susceptible to COVID-19 infections compared to those with native kidneys because of chronic immunosuppression and co-existing co-morbidities. A wide spectrum of renal pathologies has been reported from renal biopsies taken from patients with native kidneys following COVID-19 presentation. In comparison, biopsy-proven findings in the setting of kidney transplantation and COVID-19 diagnosis are seldom described. Our study aims to review early reported histological findings of transplant kidney biopsies from patients testing positive for COVID-19.

Method

This is a secondary analysis of a larger study (PROSPERO registration number: CRD42020218048) which reviewed the histopathological findings of kidney biopsies in adults with concurrent COVID-19 infection. A systematic literature search was conducted independently by two authors (HW, VJ) through ‘PubMed’, ‘Web of Science’, ‘Embase’ and ‘Medline-ProQuest’ using the following keywords: “COVID-19 AND Kidney Biopsy”, “COVID-19 AND Renal Biopsy”, “SARS-CoV-2 AND Kidney Biopsy” and “SARS-CoV-2 AND Renal Biopsy”. Articles were screened by three authors (HW, VJ, RC) for relevance and duplicates were removed. The study selection process was carried out as per the PRISMA guideline. In this analysis, we included all research articles reporting biopsies in transplanted kidneys in adults over age > 18 who tested positive with COVID-19 following a PCR swab test. We only included articles published in the English language. All relevant articles published before November 1^st 2020 were included in this review. Information regarding demographic data, co-morbidities, renal presentation, renal parameters at time of COVID-19 diagnosis, management, need for renal replacement therapy and outcomes were extracted from selected articles.

Results

Our review identified 11 cases reporting transplant kidney biopsies in patients with positive COVID-19 status. These 11 cases were reported from 7 articles, which were either single case reports or part of a case series. Mean age of the reported cases was 43.6 years ± 10.7. Transplant kidney biopsies were taken from 4 female and 7 male patients, where 7 patients were of black ethnicity. The review involved 3 live donor and 6 deceased donor transplanted kidneys, and 2 cases did not report type of kidney transplant received. All of the documented cases presented with acute kidney injury. 9 patients have essential hypertension or hypertension secondary to other co-morbidities. Biopsy findings revealed 2 cases of acute T-cell mediated and antibody mediated rejection, 2 cases of acute tubular injury, 5 cases of either FSGS or collapsing FSGS and 1 report of post-transplant kidney infarction. Acute treatment received involved different regimes. All 11 patients were eventually discharged from hospital, where 2 patients required dialysis following discharge. Table 1 describes data from the extracted cases.

Conclusion

There are multiple histological pathologies observed amongst transplant kidney biopsies taken from patients admitted following COVID-19 diagnosis. Early results suggest aggressive medical treatment to manage inflammation, transplant rejection and co-morbidities such as hypertension may optimize general and renal-specific outcomes. Collation of further cases is required to determine a clearer association between COVID-19 and characteristics demonstrated from transplant kidney biopsies.

MO284UTILITY OF SERUM IGA/C3 RATIO IN PREDICTING RENAL DISEASE PROGRESSION IN IGA NEPHROPATHY

Background and Aims:

IgA nephropathy is the most prevalent and predominantly slow progressing glomerular disease. Risk prediction tools like the international IgAN help to guide the prognosis in this group of patients. The IgA/C3 ratio has been shown to be a useful predictor of poor outcomes in Chinese cohort but such a study is lacking in the Caucasians. The study aims to investigate the utility of IgA/C3 score in predicting renal outcome in 5 years (50% decline in five years or reaching ESRD) in a Caucasian cohort.

Method

All available patients with biopsy-proven IgA nephropathy in our centre between January 2001 and December 2013 were included in this observational study (115 patients). Baseline (biopsy date) data relevant to the scores including demographics, laboratory and the histopathological features were collated at the time of biopsy. Follow up data on renal functions and renal outcome (50% decline in eGFR at 5 years) were collected until an arbitrary end date 31/12/2018. IgA/C3 ratio was available in 46 (40%) of the patients and this cohort wase split into two groups based on IgA/C3 ratio (A- ratio &lt;/=3 and B- ratio &gt;3) and analysed.

Results

We had a total of 115 patients recorded over this 13-year period. The median age of our cohort at time of biopsy was 41 years with a predominance of male gender (71%). At baseline 84% were hypertensive and 11% diabetic. 77% were on a renin-angiotensin blocker, with 53% being on a statin.

At 2 years follow-up the median decline in estimated glomerular filtration (eGFR) between the groups was similar (Group- A 2.65 ml/min vs Group- B 2 ml/min, p=0.557). At 5 years, the median decline in eGFR was higher in Group B though not statistically significant (9.3ml/min vs 4.6ml/min, p=0.475) (Table-1). At 5 years a higher IGA/C3 ratio was showing appositive corelation to the decline in eGFR (Figure–2).

Conclusion

Patients with higher IgA/C3 ratio had a higher drop in estimated glomerular filtration rate at five years of follow-up. Validation in a larger sample is warranted before this can be used clinically.