Achieving consensus on psychosocial and physical rehabilitation management for people living with kidney disease

Background

People living with chronic kidney disease (CKD) need to be able to live well with their condition. The provision of psychosocial interventions (psychological, psychiatric and social care) and physical rehabilitation management is variable across England, as well as the rest of the UK. There is a need for clear recommendations for standards of psychosocial and physical rehabilitation care for people living with CKD, and guidance for the commissioning and measurement of these services. The National Health Service (NHS) England Renal Services Transformation Programme (RSTP) supported a programme of work and modified Delphi process to address the management of psychosocial and physical rehabilitation care as part of a larger body of work to formulate a comprehensive commissioning toolkit for renal care services across England. We sought to achieve expert consensus regarding the psychosocial and physical rehabilitation management of people living with CKD in England and the rest of the UK.

Methods

A Delphi consensus method was used to gather and refine expert opinions of senior members of the kidney multi-disciplinary team (MDT) and other key stakeholders in the UK. An agreement was sought on 16 statements reflecting aspects of psychosocial and physical rehabilitation management for people living with CKD.

Results

Twenty-six expert practitioners and other key stakeholders, including lived experience representatives, participated in the process. The consensus (>80% affirmative votes) amongst the respondents for all 16 statements was high. Nine recommendation statements were discussed and refined further to be included in the final iteration of the 'Systems' section of the NHS England RSTP commissioning toolkit. These priority recommendations reflect pragmatic solutions that can be implemented in renal care and include recommendations for a holistic wellbeing assessment for all people living with CKD who are approaching dialysis, or who are at listing for kidney transplantation, which includes the use of validated measurement tools to assess the need for further intervention in psychosocial and physical rehabilitation management. It is recommended that the scores from these measurement tools be included in the NHS England Renal Data Dashboard. There was also a recommendation for referral as appropriate to NHS Talking Therapies, psychology, counselling or psychotherapy, social work or liaison psychiatry for those with identified psychosocial needs. The use of digital resources was recommended to be used in addition to face-to-face care to provide physical rehabilitation, and all healthcare professionals should be educated to recognize psychosocial and physical rehabilitation needs and refer/sign-post people with CKD to appropriate services.

Conclusion

There was high consensus amongst senior members of the kidney MDT and other key stakeholders, including those with lived experience, in the UK on all aspects of the psychosocial and physical rehabilitation management of people living with CKD. The results of this process will be used by NHS England to inform the 'Systems' section of the commissioning toolkit and data dashboard and to inform the National Standards of Care for people living with CKD.

A Genetic Risk Score Distinguishes Different Types of Autoantibody-Mediated Membranous Nephropathy

Introduction

Membranous nephropathy (MN) is the leading cause of nephrotic syndrome in adults and is characterized by detectable autoantibodies against glomerular antigens, most commonly phospholipase A2 receptor 1 (PLA2R1) and thrombospondin type-1 domain containing 7A (THSD7A). In Europeans, genetic variation in at least five loci, PLA2R1, HLA-DRB1, HLA-DQA1, IRF4, and NFKB1, affects the risk of disease. Here, we investigated the genetic risk differences between different autoantibody states.

Methods

1,409 MN individuals were genotyped genome-wide with a dense SNV array. The genetic risk score (GRS) was calculated utilizing the previously identified European MN loci, and results were compared with 4,929 healthy controls and 422 individuals with steroid-sensitive nephrotic syndrome.

Results

GRS was calculated in the 759 MN individuals in whom antibody status was known. The GRS for MN was elevated in the anti-PLA2R1 antibody-positive (N = 372) compared with both the unaffected control (N = 4,929) and anti-THSD7A-positive (N = 31) groups (p < 0.0001 for both comparisons), suggesting that this GRS reflects anti-PLA2R1 MN. Among PLA2R1-positive patients, GRS was inversely correlated with age of disease onset (p = 0.009). Further, the GRS in the dual antibody-negative group (N = 355) was intermediate between controls and the PLA2R1-positive group (p < 0.0001).

Conclusion

We demonstrate that the genetic risk factors for PLA2R1- and THSD7A-antibody-associated MN are different. A higher GRS is associated with younger age of onset of disease. Further, a proportion of antibody-negative MN cases have an elevated GRS similar to PLA2R1-positive disease. This suggests that in some individuals with negative serology the disease is driven by autoimmunity against PLA2R1.

Contactin-1 links autoimmune neuropathy and membranous glomerulonephritis

Membranous glomerulonephritis (MGN) is a common cause of nephrotic syndrome in adults, mediated by glomerular antibody deposition to an increasing number of newly recognised antigens. Previous case reports have suggested an association between patients with anti-contactin-1 (CNTN1)-mediated neuropathies and MGN. In an observational study we investigated the pathobiology and extent of this potential cause of MGN by examining the association of antibodies against CNTN1 with the clinical features of a cohort of 468 patients with suspected immune-mediated neuropathies, 295 with idiopathic MGN, and 256 controls. Neuronal and glomerular binding of patient IgG, serum CNTN1 antibody and protein levels, as well as immune-complex deposition were determined. We identified 15 patients with immune-mediated neuropathy and concurrent nephrotic syndrome (biopsy proven MGN in 12/12), and 4 patients with isolated MGN from an idiopathic MGN cohort, all seropositive for IgG4 CNTN1 antibodies. CNTN1-containing immune complexes were found in the renal glomeruli of patients with CNTN1 antibodies, but not in control kidneys. CNTN1 peptides were identified in glomeruli by mass spectroscopy. CNTN1 seropositive patients were largely resistant to first-line neuropathy treatments but achieved a good outcome with escalation therapies. Neurological and renal function improved in parallel with suppressed antibody titres. The reason for isolated MGN without clinical neuropathy is unclear. We show that CNTN1, found in peripheral nerves and kidney glomeruli, is a common target for autoantibody-mediated pathology and may account for between 1 and 2% of idiopathic MGN cases. Greater awareness of this cross-system syndrome should facilitate earlier diagnosis and more timely use of effective treatment.

A case report of breast cancer and membranous nephropathy with positive anti phospholipase A2 receptor antibodies

BACKGROUND

Testing for antibodies against podocyte phospholipase A2 receptor-1 (PLA2R) allows clinicians to accurately identify primary membranous nephropathy (MN). Secondary MN is associated with a spectrum of pathology including solid organ malignancy. PLA2R positivity in these patients occurs, although no case of PLA2R-positive MN has been definitively linked to cancer.

CASE PRESENTATION

We describe a case of biopsy-proven PLA2R-positive MN, in whom invasive ductal carcinoma of the breast was discovered. The patient underwent surgery and adjuvant chemotherapy (including cyclophosphamide) and went into a sustained complete remission of her nephrotic syndrome.

DISCUSSION AND CONCLUSIONS

Case series have reported PLA2R positivity in patients with solid organ malignancy associated MN. Our case is unusual as it is a breast malignancy, and the patients nephrotic syndrome and anti-PLA2Rab titres improved with treatment of the cancer. Here we report, to the best of our knowledge, the first case of oestrogen receptor-2 positive breast cancer associated with PLA2R positive MN in a young lady that was treated successfully by treating the malignancy.

FC 030CONTACTIN-1 IS A NOVEL ANTIGEN IN IDIOPATHIC MEMBRANOUS GLOMERULONEPHRITIS AND IN CIDP- ASSOCIATED GLOMERULONEPHRITIS

Background and Aims

Recently a number of antigens have been identified as pathogenic antibody targets in cases of primary membranous glomerulonephritis(MGN), including phospholipase A2 receptor (PLA2R), thrombospondin type 1 domain containing 7A(THSD7A), and NELL-1, while exostosin is found in secondary (lupus associated) MGN. However, other as yet undiscovered antigens are thought to exist. Although rare, there is a recognised association between chronic inflammatory demyelinating polyneuriopathy (CIDP) and nephrotic syndrome.

Method

We investigated the link between CICP and MGN and the associations with Contactin-1(CNTN1), a node of Ranvier neuronal protein, as a potential common autoantigen, by immunohistochemistry, RT-PCR and proteomic analysis of isolated glomeruli. We tested sera from 468 patients with suspected immune-mediated neuropathies, 295 with idiopathic MGN, and 210 disease controls, for CNTN1 antibodies.

Results

We describe a series of 16 patients, all presenting with CIDP, nephrotic syndrome due to MGN, and with circulating and deposited anti-contactin-1 (CNTN1) antibodies (IgG4 predominant in those tested) in the kidney. The onset and resolution of both disorders had a close temporal relationship, and the majority of cases were resistant to first-line therapies typically employed for inflammatory neuropathies, but achieved a good outcome with non-standard treatment. Importantly, four (1.4%) further patients with isolated MGN identified from a serum bank of 295 idiopathic MGN patients with no CIDP were also positive for anti-CNTN1 antibodies. CNTN1 protein was detected by mass spectroscopy within glomeruli from patients with CNTN1 antibodies, but not in healthy kidney or anti-PLA2R associated MGN. CNTN1 mRNA was found in renal cortical tissue.

Conclusion

These data provide evidence that CNTN1 antibodies precipitate both autoimmune neuropathy and MGN. The temporal correlation of these disorders, as well as the presence of CNTN1 protein and antibodies in both peripheral nerve and diseased glomeruli, supports a common antibody-mediated pathological process, and defines a new antigenic target in MGN. CNTN1 antibodies have diagnostic and therapeutic relevance, and may additionally serve as a means of monitoring disease activity in both conditions. Other factors may explain presentation with isolated neurological disease or MGN.

HEROIC: a 5-year observational cohort study aimed at identifying novel factors that drive diabetic kidney disease: rationale and study protocol

INTRODUCTION

Diabetic kidney disease (DKD) is the leading cause of end-stage kidney disease worldwide and a major cause of premature mortality in diabetes mellitus (DM). While improvements in care have reduced the incidence of kidney disease among those with DM, the increasing prevalence of DM means that the number of patients worldwide with DKD is increasing. Improved understanding of the biology of DKD and identification of novel therapeutic targets may lead to new treatments. A major challenge to progress has been the heterogeneity of the DKD phenotype and renal progression. To investigate the heterogeneity of DKD we have set up The East and North London Diabetes Cohort (HEROIC) Study, a secondary care-based, multiethnic observational study of patients with biopsy-proven DKD. Our primary objective is to identify histological features of DKD associated with kidney endpoints in a cohort of patients diagnosed with type 1 and type 2 DM, proteinuria and kidney impairment.

METHODS AND ANALYSIS

HEROIC is a longitudinal observational study that aims to recruit 500 patients with DKD at high-risk of renal and cardiovascular events. Demographic, clinical and laboratory data will be collected and assessed annually for 5 years. Renal biopsy tissue will be collected and archived at recruitment. Blood and urine samples will be collected at baseline and during annual follow-up visits. Measured glomerular filtration rate (GFR), echocardiography, retinal optical coherence tomography angiography and kidney and cardiac MRI will be performed at baseline and twice more during follow-up. The study is 90% powered to detect an association between key histological and imaging parameters and a composite of death, renal replacement therapy or a 30% decline in estimated GFR.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Bloomsbury Research Ethics Committee (REC 18-LO-1921). Any patient identifiable data will be stored on a password-protected National Health Services N3 network with full audit trail. Anonymised imaging data will be stored in a ISO27001-certificated data warehouse.Results will be reported through peer-reviewed manuscripts and conferences and disseminated to participants, patients and the public using web-based and social media engagement tools as well as through public events.

P0467THE DIRECT USE OF ORAL ANTI-COAGULANTS IN MEMBRANOUS NEPHROPATHY

Background and Aims

Barts Health has a dedicated membranous nephropathy (MN) service with 15-20 incident cases per year. Nephrotic syndrome secondary to MN in particular is associated with arterial and venous thrombosis. There is little evidence to guide optimum pharmacological prophylaxis. In those considered high risk, options include warfarin, heparin or aspirin. The advent of direct oral anti-coagulants (DOACs) offers an alternative, though evidence of efficacy is isolated to case studies.

All patients with an albumin &lt;25g/L are offered anticoagulation. We describe our use of DOACs in a large single centre MN cohort.

Method

Retrospective data MN patients between 2015-2019 was analysed. This included: demographics; frequency, type and timing of thromboembolic and bleeding events; biochemical data at initiation and cessation of agent.

Results

Total number of patients: 26

DOAC treatment courses: 30

Exposure to drug (patient days): 9899

Malignancy was excluded in all cases, with the exception of 1 case of MN secondary to cancer.

There were 3 thromboembolic events in 3 patients; all events occurred on rivaroxaban and in PLA2Rab positive MN.

Thrombotic events were all arterial, with no venous events, 2 cerebral artery infarcts and 1 lower limb arterial thrombosis. These patient’s mean initial presentation PLA2Rab titres were 164 Kunits/L (75-248) and all were nephrotic at the time of the thromboembolic event. Events were 29, 128 and 340 days post DOAC initiation. 2 of these patients had a venous thrombosis prior to DOAC initiation. Event rate: 0.11 per patient year

Safety data also demonstrated 3 bleeds in this patient cohort - all were minor as per ISTH criteria. 2 epistaxes and 1 associated with rectal prolapse, all without a haemoglobin drop.

Conclusion

Our experience is that DOACs are safe and effective in patients with MN and offer a viable anti-coagulant alternative.

Do virtual renal clinics improve access to kidney care? A preliminary impact evaluation of a virtual clinic in East London

Background

Early identification of people with CKD in primary care, particularly those with risk factors such as diabetes and hypertension, enables proactive management and referral to specialist services for progressive disease.

The 2019 NHS Long Term Plan endorses the development of digitally-enabled services to replace the ‘unsustainable’ growth of the traditional out-patient model of care.Shared views of the complete health data available in the primary care electronic health record (EHR) can bridge the divide between primary and secondary care, and offers a practical solution to widen timely access to specialist advice.

Methods

We describe an innovative community kidney service based in the renal department at Barts Health NHS Trust and four local clinical commissioning groups (CCGs) in east London. An impact evaluation of the changes in service delivery used quantitative data from the virtual CKD clinic and from the primary care electronic health records (EHR) of 166 participating practices. Survey and interview data from health professionals were used to explore changes to working practices.

Results

Prior to the start of the service the general nephrology referral rate was 0.8/1000 GP registered population, this rose to 2.5/1000 registered patients by the second year of the service. The majority (> 80%) did not require a traditional outpatient appointment, but could be managed with written advice for the referring clinician. The wait for specialist advice fell from 64 to 6 days. General practitioners (GPs) had positive views of the service, valuing the rapid response to clinical questions and improved access for patients unable to travel to clinic. They also reported improved confidence in managing CKD, and high levels of patient satisfaction. Nephrologists valued seeing the entire primary care record but reported concerns about the volume of referrals and changes to working practices.

Conclusions

‘Virtual’ specialist services using shared access to the complete primary care EHR are feasible and can expand capacity to deliver timely advice. To use both specialist and generalist expertise efficiently these services require support from community interventions which engage primary care clinicians in a data driven programme of service improvement.

Predictors of late presentation to renal dialysis: a cohort study of linked primary and secondary care records in East London

OBJECTIVES

The outcomes and experience of care for patients who start renal replacement therapy (RRT) in an unplanned manner are worse than for those who have planned care. The objective of this study was to examine the primary care predictors of unplanned starts to RRT.

DESIGN

Retrospective cohort study with linked primary care and hospital data.

SETTING

128 general practices in East London with a combined population of 1 043 346 people.

PARTICIPANTS

999 consecutive patients starting dialysis at Barts Health National Health Service Trust between September 2014 and August 2017.

PRIMARY OUTCOME MEASURES

Unplanned versus a planned start to dialysis among the cohort of 389 patients with a linked primary care record. An unplanned start to dialysis is defined as receiving nephrology care in the low clearance clinic (or equivalent) for less than 90 days. A planned start is defined as access to pre-dialysis counselling and care for at least 90 days prior to commencing dialysis.

RESULTS

The adjusted logistic regression analysis showed that the most important modifiable risk factors for unplanned dialysis were the absence of a chronic kidney disease (CKD) code in the general practice (GP) record (OR 8.02, 95% CI 3.65 to 17.63) and the absence of prescribed lipid lowering medication (OR 2.37, 95% CI 1.05 to 5.34). Other contributing factors included male gender and a greater number of long-term conditions.

CONCLUSIONS

Improving CKD coding in primary care and the additional review and clinical scrutiny associated with this may contribute to a further reduction in unplanned RRT rates.

Nephrotic Syndrome: Oedema Formation and Its Treatment With Diuretics

Oedema is a defining element of the nephrotic syndrome. Its' management varies considerably between clinicians, with no national or international clinical guidelines, and hence variable outcomes. Oedema may have serious sequelae such as immobility, skin breakdown and local or systemic infection. Treatment of nephrotic oedema is often of limited efficacy, with frequent side-effects and interactions with other pharmacotherapy. Here, we describe the current paradigms of oedema in nephrosis, including insights into emerging mechanisms such as the role of the abnormal activation of the epithelial sodium channel in the collecting duct. We then discuss the physiological basis for traditional and novel therapies for the treatment of nephrotic oedema. Despite being the cardinal symptom of nephrosis, few clinical studies guide clinicians to the rational use of therapy. This is reflected in the scarcity of publications in this field; it is time to undertake new clinical trials to direct clinical practice.

Indexing dialysis dose for gender, body size and physical activity: Impact on survival

Current practice basing dialysis dose on urea distribution volume (V) has been questioned. We explored the impact on survival of scaling dialysis dose (Kt) to parameters reflective of metabolic activity. In a multicentre prospective cohort study of 1500 patients on thrice-weekly haemodialysis, body surface area (BSA) and resting energy expenditure (REE) were estimated using validated equations and physical activity by the Recent Physical Activity Questionnaire. Total energy expenditure (TEE) was estimated from REE and physical activity data. Kt was calculated from delivered (single-pool Kt/V)*Watson V. Kt/BSA, Kt/REE and Kt/TEE were then calculated at baseline and 6 monthly during follow-up for 2 years. In adjusted Cox models Kt/TEE, Kt/BSA, Kt/REE, in that order, had lower hazard ratios for death than single-pool Kt/V. On the basis of adjusted survival differences, putative minimum target doses were estimated for Kt/BSA as 27119 ml/m² and Kt/TEE as 25.79 ml/kcal. We identified spKt/V values equivalent to these estimated targets, ranging from 1.4 to 1.8 in patient groups based on gender, body size and physical activity. For sedentary patients, the minimum target dose was 1.4 for large males, 1.5 for small males and 1.7 for women. For active patients the target was 1.8 irrespective of gender and body-weight. Patients achieving these individualised minimum targets had greater adjusted two-year survival compared to those achieving conventional minimum targets. Metabolic activity related parameters, such as Kt/TEE and Kt/BSA, may have a clinically important role in scaling haemodialysis dose. Using such parameters or their spKt/V equivalents to adjust minimum target doses based on gender, body size and habitual physical activity may have a positive impact on survival.

Impact of Allograft Nephrectomy on Second Renal Transplant Outcome

OBJECTIVES

The impact of allograft nephrectomy on the outcome of a subsequent renal transplant is unclear. This study was conducted to assess the effects of the first allograft nephrectomy on outcomes of a second transplant.

MATERIALS AND METHODS

This study included 118 patients who received a second transplant between 1994 and 2015. Before the second transplant, 59 patients did not undergo a first allograft nephrectomy (group A). Group B comprised 59 patients who had undergone a first allograft nephrectomy. We compared sensitization, acute rejection, and survival of the second graft between groups. The risk factors of a second graft loss were assessed.

RESULTS

The first graft survival was significantly longer in group A than in group B (100.6 vs 3.7 months; P < .001). Prevalence of preformed donor-specific antibodies before the second allograft was similar between both groups (28.8% vs 39.0% for group A vs group B; P = .243). Numerically higher acute rejection rates occurred in group B than in group A (23.7% vs 15.3%; P = .245). In group A, graft survival rates at 1, 3, and 5 years were 93.0%, 87.0%, and 82.3% and were significantly higher than for group B (76.7%, 69.1%, and 62.5%; P ⟨ .05). On multivariate analysis, survival of the second graft was affected by acute rejection (hazard ratio = 2.24; 95% confidence interval, 1.10-4.45; P = .027) and the interval from first graft loss to second transplant (hazard ratio = 1.11; 95% confidence interval, 1.02-1.19; P = .008).

CONCLUSIONS

A first allograft nephrectomy was associated with inferior second graft survival. We recommend that recipients of second transplants should be considered as high risk if they had undergone prior allograft nephrectomy.

New ways of working; delivering better care for people with long-term conditions

Background

The cost-effectiveness of the traditional outpatient model for specialist care provision is increasingly being questioned in view of the changing patient needs, workforce challenges and technological advances.

Setting

This report summarises two RCGP London events showcasing new ways of delivering care for long-term conditions.

Questions

What are the alternative approaches to the traditional outpatient model and do they have common themes? What are the challenges and opportunities of these new models of care?

Methods

Presentation of examples of new ways of long-term condition care delivery and round-table facilitative discussion and reflection on the challenges and solutions around service re-design and implementation, the commissioning and funding of new models of care, the facilitation of system-wide learning and the collection of data for evaluation.

Results

Different ways of delivering care for people with Chronic Kidney Disease (CKD) and Chronic Obstructive Pulmonary Disease (COPD) were presented. Most of the interventions included virtual clinics (during which patient care was reviewed by a specialist remotely without the need for a face-to-face consultation), improved communication between primary and secondary care clinicians, an element of referral triage/prioritisation, the use of trigger tools to identify people at risk of deterioration, patient education and a multi-disciplinary approach.

Discussion-conclusions

Different models to the traditional outpatient long-term condition care are feasible and can result in improvements in the quality of care and staff satisfaction. However, such initiatives require careful planning, close collaboration between health care professionals and allocation of appropriate resources and training within primary care. There is also a need for systematic evaluation of such pilots to assess their cost-effectiveness and their acceptability to clinicians and patients. This requires systematic collection of population level data, agreement on the key outcomes for evaluation and a commitment of all stakeholders to sharing learning and resources to enable continuous improvement.

Membranous nephropathy: a retrospective observational study of membranous nephropathy in north east and central London

Background

Membranous nephropathy (MN) is the leading cause of nephrotic syndrome in adults. MN is a clinically heterogeneous disease and it is difficult to accurately predict outcomes (including end stage renal failure) at presentation and whom to treat with potentially toxic therapies. We aimed to identify factors predicting outcome in MN in our cohort from two large tertiary London units by undertaking a retrospective data analysis of 148 biopsy-proven MN patients from North East and Central London between 1995 and 2015.

Methods

Review of clinical and biochemistry databases.

Results

Surprisingly, patients that reached end stage renal failure (ESRF) had a less severe nephrosis compared to those that did not develop ESRF; serum albumin 33 g/L (3.3 g/dL) versus 24 g/L (2.4 g/dL), p = 0.002 and urinary protein creatinine ratio (uPCR) 550 mg/mmol (5500 mg/g) versus 902 mg/mmol (9020 mg/g), p = 0.0124. The correlation with ESRF was strongest with the presenting creatinine; 215 μmol/L (2.43 mg/dL) compared to 81 μmol/L (0.92 mg/dL), p < 0.0001. Patients presenting with creatinine of >120 μmol/L (1.36 mg/dL; corresponding to an eGFR of ≤60 ml/min in non-Black males) had an increased rate of ESRF and a faster decline. Other traditional risk factors for progression were not significantly associated with ESRF.

Black patients presented with higher serum creatinine but no statistically significant difference in the estimated glomerular filtration rate, a higher rate of progression to ESRF and had a poorer response to treatment.

Conclusions

This ethnically diverse cohort does not demonstrate the traditional risk profile associated with development of ESRF. Thus, careful consideration of therapeutic options is crucial, as current risk modelling cannot accurately predict the risk of ESRF. Further studies are required to elucidate the role of antibodies and risk genes.

Aggression on haemodialysis units: a mixed method study

BACKGROUND

Aggression on haemodialysis units is a growing problem internationally that has received little research attention to date. Aggressive behaviour by patients or their relatives can compromise the safety and well-being of staff and other patients sharing a haemodialysis session.

OBJECTIVES

The objectives of the study were twofold: First, to identify the prevalance and nature of aggression on haemodialysis units; and second, to investigate factors that contribute to aggressive behaviour on haemodialysis units.

DESIGN AND METHODS

A cross-sectional, sequential mixed method research design was adopted, with two research methods utilised. Incidents of aggressive behaviour were recorded over a 12-month period, using a renal version of the Staff Observation Aggression Scale. Six months after the incident data collection had commenced, semi-structured qualitative interviews were conducted with 29 multidisciplinary members of staff.

RESULTS

Over 12 months, 74 aggressive incidents were recorded. The majority of incidents involved verbal aggression, and the perpetrators were a minority of patients, relatives and staff. Two patients were responsible for 38% of all incidents; both patients had mental health problems. Distinct temporal patterns to the aggressive behaviour were observed according to the day of the week and time of day.

CONCLUSION

This study demonstrates that aggression is a significant problem on haemodialysis units, with verbal aggression most prevalent. The temporal patterns to aggression observed are related to the uniqueness of the haemodialysis setting, with a distinctly different treatment environment compared with other healthcare settings.

Patient safety and estimation of renal function in patients prescribed new oral anticoagulants for stroke prevention in atrial fibrillation: a cross-sectional study

OBJECTIVE

In clinical trials of dabigatran and rivaroxaban for stroke prevention in atrial fibrillation (AF), drug eligibility and dosing were determined using the Cockcroft-Gault equation to estimate creatine clearance as a measure of renal function. This cross-sectional study aimed to compare whether using estimated glomerular filtration rate (eGFR) by the widely available and widely used Modified Diet in Renal Disease (MDRD) equation would alter prescribing or dosing of the renally excreted new oral anticoagulants.

PARTICIPANTS

Of 4712 patients with known AF within a general practitioner-registered population of 930 079 in east London, data were available enabling renal function to be calculated by both Cockcroft-Gault and MDRD methods in 4120 (87.4%).

RESULTS

Of 4120 patients, 2706 were <80 years and 1414 were ≥80 years of age. Among those ≥80 years, 14.9% were ineligible for dabigatran according to Cockcroft-Gault equation but would have been judged eligible applying MDRD method. For those <80 years, 0.8% would have been incorrectly judged eligible for dabigatran and 5.3% would have received too high a dose. For rivaroxaban, 0.3% would have been incorrectly judged eligible for treatment and 13.5% would have received too high a dose.

CONCLUSIONS

Were the MDRD-derived eGFR to be used instead of Cockcroft-Gault in prescribing these new agents, many elderly patients with AF would either incorrectly become eligible for them or would receive too high a dose. Safety has not been established using the MDRD equation, a concern since the risk of major bleeding would be increased in patients with unsuspected renal impairment. Given the potentially widespread use of these agents, particularly in primary care, regulatory authorities and drug companies should alert UK doctors of the need to use the Cockcroft-Gault formula to calculate eligibility for and dosing of the new oral anticoagulants in elderly patients with AF and not rely on the MDRD-derived eGFR.

Literature review of passenger lymphocyte syndrome following renal transplantation and two case reports

Passenger lymphocyte syndrome (PLS) is an immune-mediated hemolysis. It occurs following ABO blood group mismatched solid organ and/or bone marrow transplantation between donor and recipient. We report two cases of PLS occurring after renal transplantation. Both recipients received live related kidney transplants; one from his mother and the other from his brother. The direction of blood group transfer, from donor to recipient, was O Rh D+ to A Rh D+ in both cases. Approximately 12 days after transplantation, both recipients showed a rapid fall in their hemoglobin levels with no identifiable bleeding source. DAT positive hemolysis was confirmed and anti-A antibodies were detected in recipient sera, confirming a diagnosis of PLS. Both cases required blood transfusion support to maintain their hemoglobin and both had good renal outcomes. We have identified 99 PLS cases following renal transplant in the English literature. Previous ABO sensitization, donor blood group O to recipient blood group A or B transfer, and ciclosporin treatment have been identified as risk factors for PLS. Clinical outcomes in general are good; nonetheless, cases of graft failure and deaths have been reported. Early diagnosis and appropriate treatment are important in at risk individuals.

Hyperkalaemia in the age of aldosterone antagonism

Hyperkalaemia is well recognized as a medical emergency. However, with the publication of trials showing benefit with renin-aldosterone axis suppression in heart failure, the epidemiology of patients presenting with hyperkalaemia has changed. The reported incidence of rate of serious hyperkalaemia (>6.0 mEq/l of potassium) ranges from 6 to 12% in patients on spironolactone with congestive cardiac failure (CCF). A rational choice of therapy based on present evidence is different from the traditionally used algorithm, given our understanding of the physiology relevant to this patient group. This article discusses the changing face of hyperkalaemia and the present evidence and discusses options in treatment of hyperkalaemia.

Infliximab as long-term maintenance in steroid-resistant and recurrent sarcoidosis in a renal transplant with central nervous system involvement

Sarcoidosis is a multisystemic, granulomatous disease of unknown aetiology, which commonly involves the lungs, skin and the eyes. Renal sarcoidosis is rare. Recurrent renal sarcoidosis leading to transplant graft failure in adults has not been reported. We report a single case of steroid-resistant sarcoid with recurrence in a renal transplant and the central nervous system that was managed with infliximab. We describe successful resolution of granulomas in the transplant kidney and stabilization of renal function with catastrophic central nervous system recurrence upon withdrawal of infliximab.

Guidelines for the prevention and management of Mycobacterium tuberculosis infection and disease in adult patients with chronic kidney disease

Guidelines have been compiled by the Joint Tuberculosis Committee of the British Thoracic Society for the prevention and management of Mycobacterium tuberculosis infection and disease in patients with all grades of renal impairment.

Belatacept as maintenance immunosuppression for postrenal transplant de novo drug-induced thrombotic microangiopathy

De novo posttransplant thrombotic microangiopathy (TMA) is a complication of solid organ transplantation, which remains difficult to treat. In many cases, immunosuppressants and particularly calcineurin inhibitors, trigger TMA. Although withdrawing the offending drug may lead to resolution of TMA, graft and patient outcomes are poor. Specific treatments, including plasma exchange, have not gained widespread acceptance in those with fulminant disease and new approaches to the condition are urgently needed. We report a case of posttransplant de novo TMA presenting serially in association with ciclosporin, tacrolimus and sirolimus in a young recipient of a living donor kidney transplant. We describe a patient treated with belatacept, a novel CTLA4 Ig fusion protein, as ongoing maintenance immunosuppression to allow avoidance of conventional agents once associated with TMA. We report excellent early graft outcome, with no adverse events using this strategy. We suggest that belatacept may have a role in this traditionally difficult-to-treat group of patients.

Resolution of cast nephropathy following free light chain removal by haemodialysis in a patient with multiple myeloma: a case report

INTRODUCTION

Acute renal failure in multiple myeloma is most frequently caused by cast nephropathy, when excess monoclonal free light chains co-precipitate with Tamm-Horsfall protein in the distal nephron, causing tubular obstruction. The natural history of cast nephropathy after diagnosis is unknown. This report provides supporting histological evidence that, as serum free light chain concentrations fall, intratubular casts may resolve within weeks.

CASE PRESENTATION

We report the case of a 61-year-old Caucasian woman who presented with multiple myeloma and dialysis-dependent acute renal failure, with serum kappa free light chain concentrations of 15,700 mg/litre (normal range 3.3 to 19.4 mg/litre). Renal biopsy demonstrated cast nephropathy with waxy casts in distal tubules and collecting ducts. There was an interstitial inflammatory cell infiltrate with diffuse fibrosis and tubular atrophy. Following rehydration, chemotherapy and free light chain removal using high cut-off haemodialysis, free light chain concentrations fell to less than 5% of the starting level (500 mg/litre). A repeat renal biopsy 6 weeks after the first showed resolution of cast nephropathy.

CONCLUSION

These observations indicate that cast nephropathy can quickly resolve on rapid reduction of monoclonal serum free light chains. This has important implications for the development of treatment strategies aimed at improving renal recovery rates for patients in this setting.

Trisodium citrate 46.7% selectively and safely reduces staphylococcal catheter-related bacteraemia

BACKGROUND

Trisodium citrate (TSC) 30% has been shown in a randomized control trial to be an effective antimicrobial catheter locking solution, able to significantly reduce catheter-related bacteraemia (CRB) in haemodialysis patients. Since that report, the formulation in Europe has been changed to 46.7% TSC without confirmatory data on efficacy. We report a 55 915 patient-day at risk experience in tunnelled lines of 46.7% TSC, emphasizing efficacy and changes in microbiology seen.

METHODS

On 1 July 2006, inter-dialytic catheter locking solution was changed from 5000 IU/ml heparin to Citra-lock(TM) (46.7% TSC) in all haemodialysis patients at Barts and the London Renal Unit dialysing through an incident or prevalent tunnelled catheter. Prospectively collected blood culture data for the 6 months prior to the switch and 3 months at the end of the first year of TSC use were analysed. TSC tolerability was excellent with only a single withdrawal for intolerance of the agent. No major adverse events were reported.

RESULTS

A major fall in CRB rates was noticed with a change from heparin (2.13/1000 catheter-days) in 2006 to TSC (0.81/1000 catheter-days) in 2007. This was due to significant reductions in staphylococcal CRB, true for sensitive, methicillin-resistant and coagulase-negative staphylococci. No increase in catheter malfunction was observed.

CONCLUSIONS

We found that 46.7% TSC is a safe, convenient and highly effective catheter locking solution, leading to significant reduction in CRB largely by preventing staphylococcal bloodstream infections. Given that Staphylococcus aureus in particular is associated with serious and often disseminated infection, TSC seems to be a powerful tool for dialysis units.

Inappropriately low aldosterone concentrations in adults with AIDS-related diarrhoea in Zambia: a study of response to fluid challenge

BACKGROUND

Chronic diarrhoea is one of the most debilitating consequences of HIV infection in sub-Saharan Africa and it carries a high mortality rate. We report unexpectedly low concentrations of circulating aldosterone in 12 patients (6 men, 6 women) in the University Teaching Hospital, Lusaka, who all had diarrhoea for over one month. Changes in serum electrolytes, blood pressure, Karnofsky score and serum aldosterone concentration were being monitored during a short study of responses to saline infusion (3 litres/24 h) over 72 hours.

FINDINGS

At baseline, 9/12 (75%) of the patients were hyponatraemic, 10/11 (91%) were hypokalaemic, and 6/12 (50%) had undetectable aldosterone concentrations. Blood pressure and Karnofsky score rose and creatinine concentration fell in response to the infusion.

CONCLUSION

Circulating aldosterone concentrations were inappropriately low and complicate the profound electrolyte deficiencies resulting from chronic diarrhoea. Management of these deficiencies needs to be more aggressive than is currently practised and consideration should be given to a formal clinical trial of mineralocorticoid replacement in these severely ill patients. If the inappropriately low aldosterone reflects a general adrenal failure, it may explain a considerable proportion of the high mortality seen both before and after initiation of anti-retroviral therapy.

Renal disease and the mouth

Oral manifestations of renal disease are common. They may present as unique signs of multi-system disease affecting the kidneys (such as vasculitis), or as common oral pathologies found at an increased prevalence in patients with end-stage renal disease. Despite more oral and dental disease in patients on renal replacement therapy, attendance at dental clinics is infrequent, and physician awareness of the problem is low. In our short review, aimed at renal, transplant, and general physicians, we discuss the link between clinical changes in the mouth and multi-systemic disease involving the kidney. We suggest a standardized approach to oral examination to increase diagnostic yield and discuss common oral complications in patients on dialysis or successfully transplanted. Finally, we suggest potential treatments for oral disease that nephrologists might safely institute.

Single UK centre experience on the treatment of PD peritonitis--antibiotic levels and outcomes

BACKGROUND

There are few studies of the pharmacokinetics of vancomycin and gentamicin in peritoneal dialysis (PD) patients and the influence of antibiotic concentrations on treatment outcome. Concerns about resistance to ceftazidime and potential of aminoglycoside toxicity make the choice of empiric antibiotic difficult.

METHODS

We retrospectively collected data from 613 patients on PD between 1 June 2002 and 31 December 2005. During this time, we adopted a protocol that minimized aminoglycoside exposure to patients with residual renal function and carefully monitored serum antibiotic concentrations.

RESULTS

There were no statistical differences in mean day-5 vancomycin concentrations for continuous ambulatory peritoneal dialysis (CAPD) vs automated peritoneal dialysis (APD) and for anuric vs not-anuric patients. However, low levels (<12 mg/l) were recorded for 12.8% CAPD and 15% APD patients. These remained low at day 10 in 16% patients (25% if not anuric) despite incremental dosing. Vancomycin concentration did not predict cure or relapse of Gram-positive or culture-negative peritonitis. Gentamicin concentration (>2 mg/l in >50% patients) did not predict outcome of Gram-negative and culture-negative peritonitis. Moreover, cure rates were the same irrespective of whether gentamicin was continued for 14 days or was switched to ceftazidime after 5 days.

CONCLUSION

We have confirmed that the International Society for Peritoneal Dialysis (ISPD) dosing guideline for vancomycin in CAPD and APD patients produces adequate serum concentrations of the antibiotics in the vast majority. However, large incremental dosing of vancomycin is needed if day-5 levels are low; especially for not-anuric patients. Whilst evidence of gentamicin toxicity in PD remains controversial, ISPD dosing regimen resulted in high levels for >50% patients. High gentamicin concentrations did not correlate with treatment success, but switching gentamicin to ceftazidime at day 5 appeared safe and limited aminoglycoside exposure. Increasing vancomycin and gentamicin concentrations do not appear to improve cure rates and alternative strategies (such as combination treatment) should be considered for future research.

Increased L-arginine transport via system b0,+ in human proximal tubular cells exposed to albumin

Albumin has complex effects on PTECs (proximal tubular epithelial cells) and is able to stimulate growth or injury depending on its bound moieties. Albumin itself is a mitogen, inducing proliferation through a number of pathways. In PTEC exposed to purified albumin, polyamines are required for entry into the cell cycle and are critical for proliferation. Polyamines are synthesized from L-ornithine (itself derived by the action of arginase on L-arginine), and the transport and availability of L-arginine may thus be important for subsequent polyamine-dependent proliferation. In the present study we investigated radiolabelled cationic amino-acid transport in cultured PTEC exposed to 20 mg/ml ultrapure recombinant human albumin, describing the specific kinetic characteristics of transport and the expression of transporters. L-[3H]Arginine transport capacity in human PTEC is increased after exposure for 24 h to human albumin, mediated by the broad-scope high-affinity system b0,+ and, to a lesser extent, system y+L (but not system y+) transport. Increased transport is associated with increased b0,+-associated transporter expression. Inhibition of phosphoinositide 3-kinase, a key regulator of albumin endocytosis and signalling, inhibited proliferation, but had no effect on the observed increase in transport. PTEC proliferated in response to albumin. L-Lysine, a competitive inhibitor of L-arginine transport, had no effect on albumin-induced proliferation; however, arginine deprivation effectively reversed the albumin-induced proliferation observed. In conclusion, in PTEC exposed to albumin, increased L-arginine transport is mediated by increased transcription and activity of the apical b0,+ transport system. This may make L-arginine available as a substrate for the downstream synthesis of polyamines, but is not critical for cell proliferation.

Albumin stimulates cell growth, L-arginine transport, and metabolism to polyamines in human proximal tubular cells

BACKGROUND

Pure albumin stimulates proximal tubular epithelial cell (PTEC) proliferation, and may have a role in homeostasis in health, as well as in disrupted PTEC turnover in proteinuric nephropathies. We investigated a role for arginine and its metabolites, the polyamines, in this process, given the ability of polyamines to trigger proliferation in other mammalian cells.

METHODS

[(3)H]-L-arginine uptake was examined after incubation with 20 mg/mL recombinant human serum albumin (rHSA) in HK-2 PTEC monolayers. Nitric oxide synthase (NOS) and arginase activity was measured; NOS, arginase, and ornithine decarboxylase (ODC) expression was identified by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). Polyamine synthesis and intracellular amino acid concentrations were compared using high-performance liquid chromatography, and cell growth measured by [(3)H]-thymidine incorporation.

RESULTS

In HK-2 PTEC exposed to 20 mg/mL rHSA for 24 hours, cell proliferation as determined by [(3)H]-thymidine incorporation was increased. In parallel, L-arginine transport capacity was increased in a dose- and time-dependent manner. This effect was specific to rHSA, and was not seen with transferrin or immunoglobulin G. The intracellular concentration of L-arginine remained unchanged, although L-ornithine was increased with rHSA incubation. rHSA up-regulated type II arginase mRNA, and increased arginase activity, although no difference in nitric oxide synthase expression or activity was seen. ODC mRNA was increased, as were intracellular polyamine concentrations. alpha-Difluoromethylornithine (DFMO), an ODC inhibitor, reduced intracellular polyamine concentrations and rHSA-induced cell proliferation to control levels.

CONCLUSION

The arginine-ornithine-polyamine pathway appears enhanced in PTEC incubated with rHSA and is involved in cellular proliferation; this may offer novel approaches to understanding progressive proteinuric nephropathies.