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.

Humoral Response in Hemodialysis Patients Following COVID-19 Vaccination and Breakthrough Infections during Delta and Omicron Variant Predominance.

BACKGROUND: The advancement of COVID-19 vaccination programs globally has been viewed as an integral strategy to reduce both the number of COVID-19 cases and consequential complications of COVID-19, particularly for high-risk patient groups. There are limited data on the antibody response and protection from disease infection and severity in patients requiring hemodialysis (HD) following COVID-19 vaccination during the Delta and Omicron variant predominance. We conducted a study aiming to evaluate humoral immunity derived from two different COVID-19 vaccines administered to our in-centre HD population and investigated the characteristics of breakthrough COVID-19 infections occurring post-vaccination within this population. METHODS: This is a prospective observational study including patients receiving HD at Salford Royal Hospital. The first and second doses of COVID-19 vaccinations (Pfizer BioNTech BNT162b2 or Oxford AstraZeneca ChAdOx1 nCoV-19) were administered to this patient cohort since January 2021. The incidence of any breakthrough COVID-19 infections occurring in double vaccinated patients between 1 April 2021 and 15 January 2022 was recorded. Patients were screened weekly with nasal and pharyngeal nasopharyngeal swabs for real-time Reverse Transcription Polymerase Chain Reaction (rRT-PCR) for COVID-19, whilst SARS-CoV-2 antibody testing was performed alongside monthly routine HD bloods. RESULTS: Four hundred eleven patients receiving HD were included in this study, of which 170 of 178 patients (95.5%) with available data on antibody status following two doses of the Pfizer BioNTech BNT162b2 vaccination had detectable antibody response, whilst this was the case for 97 of 101 patients (96.1%) who received two doses of the Oxford AstraZeneca ChAdOx1 nCoV-19 vaccine. For 12 seronegative patients who received a booster vaccine (third dose), nine seroconverted, while one remained negative and two were not tested. No statistically significant differences were observed with regards to antibody status between those receiving Pfizer BioNTech BNT162b2 and Oxford AstraZeneca ChAdOx1 nCoV-19 vaccines. Sixty-three of 353 patients with two doses of COVID-19 vaccination had breakthrough COVID-19 infection (40 during Delta and 23 during Omicron variant predominance). Of the 40 patients during the delta period, five were admitted into hospital and there were two reported deaths due to COVID-19-related illness. There were no COVID-19 associated hospitalizations or deaths during the Omicron variant predominance. CONCLUSIONS: The vast majority of HD patients who received two doses of the Pfizer BioNTech BNT162b2 or Oxford AstraZeneca ChAdOx1 nCoV-19 vaccinations developed detectable antibody responses. Our results support the value of booster vaccination with mRNA-based COVID-19 vaccine in HD patients and highlight the need for ongoing surveillance programmes with rRT-PCR and antibody testing for timely detection of positive cases.

Safely reducing haemodialysis frequency during the COVID-19 pandemic.

BACKGROUND: Patients undergoing haemodialysis (HD) are at higher risk of developing worse outcomes if they contract COVID-19. In our renal service we reduced HD frequency from thrice to twice-weekly in selected patients with the primary aim of reducing COVID 19 exposure and transmission between HD patients. METHODS: Dialysis unit nephrologists identified 166 suitable patients (38.4% of our HD population) to temporarily convert to twice-weekly haemodialysis immediately prior to the peak of the COVID-19 pandemic in our area. Changes in pre-dialysis weight, systolic blood pressure (SBP) and biochemistry were recorded weekly throughout the 4-week project. Hyperkalaemic patients (serum potassium > 6.0 mmol/L) were treated with a potassium binder, sodium bicarbonate and received responsive dietary advice. RESULTS: There were 12 deaths (5 due to COVID-19) in the HD population, 6 of which were in the twice weekly HD group; no deaths were definitively associated with change of dialysis protocol. A further 19 patients were either hospitalised and/or developed COVID-19 and thus transferred back to thrice weekly dialysis as per protocol. 113 (68.1%) were still receiving twice-weekly HD by the end of the 4-week project. Indications for transfer back to thrice weekly were; fluid overload (19), persistent hyperkalaemia (4), patient request (4) and compliance (1). There were statistically significant increases in SBP and pre-dialysis potassium during the project. CONCLUSIONS: Short term conversion of a large but selected HD population to twice-weekly dialysis sessions was possible and safe. This approach could help mitigate COVID-19 transmission amongst dialysis patients in centres with similar organisational pressures.

Small vessel multi-organ vasculitis and marantic endocarditis complicating rheumatoid arthritis.

Marantic endocarditis is an extremely rare extra-articular complication of rheumatoid arthritis. To date, documented cases typically occurred in the absence of other systemic features of disease activity. We report a rare and exceptional example of marantic endocarditis secondary to fulminant systemic rheumatoid vasculitis with multi-organ disease. Findings from this case and literature review suggest that marantic endocarditis associated with rheumatoid vasculitis displays a tendency to affect the mitral valve with high risk of embolization.

Effect of a Quality Improvement Program to Improve Guideline Adherence and Attainment of Clinical Standards in Dialysis Care: Report of Outcomes in Year 1.

BACKGROUND: Best practice in dialysis is synthesised in clear international guidelines. However, a large gap remains between the international guidelines and the actual delivery of care. In this paper, we report outcomes for the first year of a multifaceted dialysis improvement programme in our network. METHODS: One year collaborative involving 3 haemodialysis units and a peritoneal dialysis (PD) programme involving 299 dialysis patients. Each unit addressed a different indicator (unit A - catheter-related bloodstream infection [CRBSI], unit B - pre-dialysis blood pressure [BP], unit C - dialysis dose, unit D - anaemia) with a shared aim to match the top 10% in the UK. Tailored multifaceted approaches include a modified collaborative methodology with an aim, framework, driver diagram, learning sessions, facilitated meetings, plan-do-study-act cycles and continuous measurement. Analysis of outcomes, costings, erythropoietin stimulating agent and iron use, and safety culture attributes. RESULTS: Unit A reduced CRBSI from 2.65 to 0.5 per 1,000 catheter days (p = 0.02). Unit B improved attainment of target BP from 37.5 to 67.2% (p = 0.003). Unit C improved attainment of target urea reduction ratio from 75.8 to 91.4% (p = 0.04). PD unit D improved attainment of target haemoglobin from 45.5 to 62.7% (p = 0.01), with no significant change in the indicators in a non-intervention unit. Safety culture attributes improved. Costs associated with admission for fluid overload and infection, erythropoietin, iron and thrombokinase use decreased 36% (£415,620-£264,143). CONCLUSIONS: Units that took part in this collaborative improved guideline adherence compared both to their own pre-intervention performance and a non-intervention unit. Such multifaceted interventions are a useful methodology to improve dialysis care.

CMV disease complicating induction immunosuppressive treatment for ANCA-associated vasculitis.

We present a case of a 71-year-old woman who initially presented with renal-limited antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. Following standard therapy with cyclophosphamide, steroids and plasma exchange, her renal function began to improve. However, despite appropriate treatment, her renal function subsequently deteriorated and she suffered haemoptysis. Owing to diagnostic uncertainty, bronchoscopy and a repeat renal biopsy were performed. The bronchoscopy washings demonstrated positivity for cytomegalovirus (CMV) DNA, and in combination with a positive serum CMV PCR, immunosuppression was withheld. Treatment with ganciclovir was started. Repeat renal biopsy demonstrated active vasculitis and, following successful treatment of CMV disease, immunosuppression was re-started alongside prophylactic valganciclovir. This resulted in a successful outcome for the patient. Pulmonary CMV disease may mimic pulmonary disease associated with vasculitis, posing a diagnostic challenge to clinicians. We recommend a low threshold when testing for CMV in these patients.

Myosin heavy chain-9-related disorders (MYH9-RD): a case report.

Myosin heavy chain-9-related disorders (MYH9-RDs) are a group of autosomal-dominant disorders caused by mutations in the MYH9 gene. The features include congenital macrothrombocytopaenia, inclusion bodies in neutrophils and a variable risk of developing sensorineural deafness, progressive renal impairment and presenile cataracts. A 44-year-old Caucasian man was initially thought to have Alport's syndrome and thrombocytopaenia secondary to idiopathic thrombocytopaenic purpura (ITP). A detailed family history and genetic analysis revealed a diagnosis of MYH9-RD. This case highlights the implications of a delayed diagnosis and the ongoing challenges encountered during management of individuals with this condition.

Lipid-lowering therapy in chronic kidney disease: is there a role for ezetimibe?

The use of lipid-lowering therapy (LLT) in chronic kidney disease (CKD) results in a reduction in atherosclerotic cardiovascular events but not mortality. The risk reduction for patients on dialysis appears to be less than in pre-dialysis CKD. These findings may be due to the higher rate of non-atherosclerotic cardiovascular disease found in end-stage disease. Because of this, the role of LLT is less clear in CKD than in the general population. This review outlines the results of recent trials of LLT, particularly Ezetimibe, and implications for patients with CKD. The evidence in favour of lipid lowering in CKD comes largely from the SHARP study. This study used combined simvastatin and Ezetimibe to reduce cholesterol. Though the benefits of statins are well proven, there is no evidence that Ezetimibe independently reduces cardiovascular events in any population. Data which support the use of Ezetimibe show only that it effectively reduces cholesterol. Surrogate end-point data are contentious. Some studies suggest benefit whilst others suggest off-target effects that question the validity of Ezetimibe in the absence of quality cardiovascular outcome data.

Urinary proteomic analysis of chronic allograft nephropathy.

The pathogenesis of progressive renal allograft injury, which is termed chronic allograft nephropathy (CAN), remains obscure and is currently defined by histology. Prospective protocol-biopsy trials have demonstrated that clinical and standard laboratory tests are insufficiently sensitive indicators of the development and progression of CAN. The study aim was to determine if CAN could be characterized by urinary proteomic data and identify the proteins associated with disease. The urinary proteome of 75 renal transplant recipients and 20 healthy volunteers was analyzed using surface enhanced laser desorption and ionization MS. Patients could be classified into subgroups with normal histology and Banff CAN grades 2-3 with a sensitivity of 86% and a specificity of 92% by applying the classification algorithm Adaboost to urinary proteomic data. Several urinary proteins associated with advanced CAN were identified including α1-microglobulin, ß2-microglobulin, prealbumin, and endorepellin, the antiangiogenic C-terminal fragment of perlecan. Increased urinary endorepellin was confirmed by ELISA and increased tissue expression of the endorepellin/perlecan ratio by immunofluoresence analysis of renal biopsies. In conclusion, analysis of urinary proteomic data has further characterized the more severe CAN grades and identified urinary endorepellin, as a potential biomarker of advanced CAN.

Diagnostic potential of urine proteome: a broken mirror of renal diseases.

This brief overview of studies into the urine proteome illustrates its potential value for diagnostic, prognostic, and pathophysiologic discovery. Hypothesis-targeted investigations of individual proteins as well as proteome-wide searches for urinary biomarkers of various diseases and their progression are reviewed. The majority of urine proteins appear as cleavage products that are found not only as free solutes but also in secreted membrane vesicles called exosomes. Described are several recent examples of important diagnostic findings using urine proteomics along with the idea that signature profiles of injury to individual nephron segments can be measured by this technology. Shared are some thoughts on the most challenging step: Integration of seemingly unrelated findings of various protein fragments into a rational pathogenetic pathway(s). The future chance that the centuries-old technique of uroscopy will reveal its secrets using modern proteomic approaches makes gradual improvement.

Chronic NOS inhibition actuates endothelial-mesenchymal transformation.

Chronic kidney diseases are accompanied by the accumulation of substances like asymmetric dimethylarginine, phenylacetic acid, homocysteine, and advanced glycation end products, known to either inhibit endothelial nitric oxide synthase (eNOS) or uncouple it, consequently limiting the amount of available nitric oxide (NO). Reduced bioavailability of NO induces endothelial dysfunction. An early loss of peritubular capillaries in tubulointerstitial fibrotic areas and injury to endothelial cells have been linked to progressive renal disease. Screening endothelial genes in cells treated with NOS inhibitors showed upregulation of collagen XVIII, a precursor of a potent antiangiogenic substance, endostatin. This finding was confirmed at the level of mRNA and protein expression. Tie-2 promoter-driven green fluorescent protein mice treated with nonhypertensinogenic doses of a NOS inhibitor exhibited upregulation of collagen XVIII/endostatin and rarefaction of capillary profiles. This was accompanied by the increased expression of transforming growth factor-beta and connective tissue growth factor in the kidney. Occasional endothelial cells expressed both the marker of endothelial lineage (green fluorescent protein) and mesenchymal marker (alpha-smooth muscle actin or calponin). In vitro studies of endothelial cells treated with asymmetric dimethylarginine showed decreased expression of eNOS and Flk-1 and enhanced expression of calponin and fibronectin, additional markers of smooth muscle and mesenchymal cells. These cells overexpressed transforming growth factor-beta and connective tissue growth factor, as well as endostatin. In conclusion, data presented here 1) ascribe to NO deficiency in endothelial cells the function of a profibrotic stimulus associated with the expression of an antiangiogenic fragment of collagen XVIII (endostatin) and 2) provide evidence of endothelial-mesenchymal transdifferentiation in the course of inhibition of NOS by a pathophysiologically important antagonist, asymmetric dimethylarginine. Both mechanisms may account for microvascular rarefaction.

Technology Insight: renal proteomics--at the crossroads between promise and problems.

Knowledge of the human genome has fertilized research in the embryonic field of proteomics. The aim of this Review is to examine the recent application of emerging proteomic technologies to diagnosis of renal disease. We discuss the roles, efficacy and diagnostic potential of different proteomic approaches, focusing on current difficulties and potential solutions. Our rudimentary knowledge of the healthy human urine proteome is described, as are studies that have sought to use the urinary proteome as a tool for diagnosis of renal disease. Vignettes of renal proteome are also presented. The integral role of bioinformatics, and the need for standardized sample preservation and reporting of results, are discussed.

Urinary proteome of steroid-sensitive and steroid-resistant idiopathic nephrotic syndrome of childhood.

The response to steroid therapy is used to characterize the idiopathic nephrotic syndrome (INS) of childhood as either steroid-sensitive (SSNS) or steroid-resistant (SRNS), a classification with a better prognostic capability than renal biopsy. The majority (approximately 80%) of INS is due to minimal change disease but the percentage of focal and segmental glomerulosclerosis is increasing. We applied a new technological platform to examine the urine proteome to determine if different urinary protein excretion profiles could differentiate patients with SSNS from those with SRNS. Twenty-five patients with INS and 17 control patients were studied. Mid-stream urines were analyzed using surface enhanced laser desorption and ionization mass spectrometry(SELDI-MS). Data were analyzed using multiple bioinformatic techniques. Patient classification was performed using Biomarker Pattern Software and a generalized form of Adaboost and predictive models were generated using a supervised algorithm with cross-validation. Urinary proteomic data distinguished INS patients from control patients, irrespective of steroid response, with a sensitivity of 92.3%, specificity of 93.7%, positive predictive value of 96% and a negative predictive value of 88.2%. Classification of patients as SSNS or SRNS was 100%. A protein of mass 4,144 daltons was identified as the single most important classifier in distinguishing SSNS from SRNS. SELDI-MS combined with bioinformatics can identify different proteomic patterns in INS. Characterization of the proteins of interest identified by this proteomic approach with prospective clinical validation may yield a valuable clinical tool for the non-invasive prediction of treatment response and prognosis.

Emerging studies of the urinary proteome: the end of the beginning?

PURPOSE OF REVIEW: Urinary proteomics is a rapidly growing field, holding the promise of discovery of biomarkers of various disease processes and elucidation of pathophysiologic mechanisms of disease states. This may be true not only for renal disease but for diseases of other organs and systemic disorders. RECENT FINDINGS: Recent advances in separation technologies and rapid, high-throughput, and accurate protein detection and identification now permit rigorous examination of complex biological fluids. This review sketches the progress achieved in recent years and the existing hurdles in describing a normal urinary proteome, its aberrations in pathological conditions, and the search for biomarkers of several renal and non-renal diseases. SUMMARY: The first wave of urinary proteomic studies has now arrived and their results are summarized. Future lines of investigation are delineated.

Endothelial microparticles affect angiogenesis in vitro: role of oxidative stress.

Endothelium-derived microparticles have recently been described as a new marker of endothelial cell dysfunction. Increased levels of circulating microparticles have been documented in inflammatory disorders, diabetes mellitus, and many cardiovascular diseases. Perturbations of angiogenesis play an important role in the pathogenesis of these disorders. We demonstrated previously that isolated endothelial microparticles (EMPs) impair endothelial function in vitro, diminishing acetylcholine-induced vasorelaxation and nitric oxide production by rat aortic rings and simultaneously increasing superoxide production. Herein, using the Matrigel assay of angiogenesis in vitro and a topological analysis of the capillary-like network by human umbilical vein endothelial cells (HUVECs), we investigated the effects of EMPs on formation of the vascular network. All parameters of angiogenesis were affected by treatment for 48 h with isolated EMPs in a concentration of 10(5) but not 10(3) or 10(4) EMPs/ml. The effects included decreases in total capillary length (24%), number of meshes (45%), and branching points (36%) and an increase in mesh area (38%). The positional and topological order indicated that EMPs affect angiogenic parameters uniformly over the capillary network. Treatment with the cell-permeable SOD mimetic Mn(III)tetrakis(4-benzoic acid) porphyrin chloride (Mn-TBAP) partially or completely restored all parameters of angiogenesis affected by EMPs. EMPs reduced cell proliferation rate and increased apoptosis rate in time- and dose-dependent manners, and this phenomenon was also prevented by Mn-TBAP treatment. Our data demonstrate that EMPs have considerable impact on angiogenesis in vitro and may be an important contributor to the pathogenesis of diseases that are accompanied by impaired angiogenesis.

Endothelial cell dysfunction: the syndrome in making.

Endothelial cell dysfunction is emerging as the ultimate culprit for diverse cardiovascular diseases and cardiovascular complications in patients with chronic renal diseases, yet the definition of this new syndrome, its pathophysiology and therapy remain poorly defined. Here, we summarize some molecular mechanisms leading from hyperhomocysteinemia, elevated asymmetric dimethylarginine (ADMA) and advanced glycation end products (AGEs)-modified proteins to atherogenic endothelial phenotype and offer a model of endothelial dysfunction based on the interconnectedness of diverse functions.

Bioinformatic analysis of the urine proteome of acute allograft rejection.

The urinary proteome in health and disease attracts increasing attention because of the potential diagnostic and pathophysiologic biomarker information carried by specific excreted proteins or their constellations. This cross-sectional study aimed to analyze the urinary proteome in patients with biopsy-proven acute rejection (n = 23) compared with transplant recipients with stable graft function (n = 22) and healthy volunteers (n = 20) and to correlate this with clinical, morphologic, and laboratory data. Urine samples were preadsorbed on four different protein chip surfaces, and the protein composition was analyzed using a surface-enhanced laser desorption/ionization time-of-flight mass spectrometer platform. The data were analyzed using two independent approaches to sample classification. Patients who experienced acute rejection could be distinguished from stable patients with a sensitivity of 90.5 to 91.3% and a specificity of 77.2 to 83.3%, depending on the classifier used. Protein masses that were important in constructing the classification algorithms included those of mass 2003.0, 2802.6, 4756.3, 5872.4, 6990.6, 19,018.8, and 25,665.7 Da. Normal urine was distinguished from transplant urine using a protein marker of mass 78,531.2 Da with both a sensitivity and a specificity of 100%. In conclusion, (1) urine proteome in transplant recipients with stable graft function was significantly different from healthy control subjects, and (2) acute rejections were characterized by a constellation of excreted proteins. Analysis of the urinary proteome may expedite the noninvasive prediction of acute graft rejection, thus importantly assisting in establishing the diagnosis.

Madura foot in the U.K.: fungal osteomyelitis after renal transplantation.

We report the case of an ethnic Asian patient who attended the renal transplant follow-up clinic complaining of pain in the right great toe. He had undergone transplantation nine months earlier and was maintained on triple immunosuppression. Initially, a clinical diagnosis of gout was made and the patient treated with analgesia. Two weeks later he remained symptomatic and developed a discharging sinus on his toe. A plain X-ray revealed a lytic lesion with minimal periosteal reaction. Aspiration of his first right metatarsal phalangeal joint was performed and fungal hyphae were observed in the fluid. Subsequently, despite surgical debridement and treatment with Itraconozaole amputation of the toe was required. Microbiological analysis revealed the organism to be Madurella grisea,which was resistant to both Itraconazole and Amphotericin B. He has remained well since amputation. We believe this to be the first case of Madurella infection to be described in a transplant patient.