Effects of rare kidney diseases on kidney failure: a longitudinal analysis of the UK National Registry of Rare Kidney Diseases (RaDaR) cohort.

BACKGROUND: Individuals with rare kidney diseases account for 5-10% of people with chronic kidney disease, but constitute more than 25% of patients receiving kidney replacement therapy. The National Registry of Rare Kidney Diseases (RaDaR) gathers longitudinal data from patients with these conditions, which we used to study disease progression and outcomes of death and kidney failure. METHODS: People aged 0-96 years living with 28 types of rare kidney diseases were recruited from 108 UK renal care facilities. The primary outcomes were cumulative incidence of mortality and kidney failure in individuals with rare kidney diseases, which were calculated and compared with that of unselected patients with chronic kidney disease. Cumulative incidence and Kaplan-Meier survival estimates were calculated for the following outcomes: median age at kidney failure; median age at death; time from start of dialysis to death; and time from diagnosis to estimated glomerular filtration rate (eGFR) thresholds, allowing calculation of time from last eGFR of 75 mL/min per 1·73 m2 or more to first eGFR of less than 30 mL/min per 1·73 m2 (the therapeutic trial window). FINDINGS: Between Jan 18, 2010, and July 25, 2022, 27 285 participants were recruited to RaDaR. Median follow-up time from diagnosis was 9·6 years (IQR 5·9-16·7). RaDaR participants had significantly higher 5-year cumulative incidence of kidney failure than 2·81 million UK patients with all-cause chronic kidney disease (28% vs 1%; p<0·0001), but better survival rates (standardised mortality ratio 0·42 [95% CI 0·32-0·52]; p<0·0001). Median age at kidney failure, median age at death, time from start of dialysis to death, time from diagnosis to eGFR thresholds, and therapeutic trial window all varied substantially between rare diseases. INTERPRETATION: Patients with rare kidney diseases differ from the general population of individuals with chronic kidney disease: they have higher 5-year rates of kidney failure but higher survival than other patients with chronic kidney disease stages 3-5, and so are over-represented in the cohort of patients requiring kidney replacement therapy. Addressing unmet therapeutic need for patients with rare kidney diseases could have a large beneficial effect on long-term kidney replacement therapy demand. FUNDING: RaDaR is funded by the Medical Research Council, Kidney Research UK, Kidney Care UK, and the Polycystic Kidney Disease Charity.

Longitudinal Analysis of Prophylactic Anticoagulation in Primary Nephrotic Syndrome: Low Incidence of Thromboembolic Complications.

Introduction: Thromboembolic events (TEEs) are a serious and potentially fatal complication of nephrotic syndrome (NS). Despite this, there is a lack of evidence examining the benefits of prophylactic anticoagulation (PAC) in NS. It was our objective to review the risk factors, rates of TEEs, and patterns of PAC in patients with primary NS, with the aim to provide a pragmatic approach to PAC in primary NS. Methods: This is a retrospective longitudinal cohort study of adult patients with primary NS. Included were as follows: biopsy-proven minimal change disease and focal segmental glomerulosclerosis (described as a combined podocytopathy cohort) plus membranous nephropathy (MN) over an 8-year period from a single centre. Anticoagulation practice, TEEs, and longer term outcomes were recorded. Results: Fifty-four patients with MN and 48 patients with podocytopathies were included. Baseline demographics and severity of NS were comparable. Those with MN were more likely to develop TEE 12 (22%) versus 4 (8%) (p = 0.027) though this difference was predominantly seen at index diagnosis. Only 2 patients developed TEEs during active incident NS. Rates of PAC were similar when comparing MN (53%) and podocytopathies (58%). Those with a serum albumin <20 g/L and HAS-BLED score <3 were most likely to receive PAC (22/30, 73% in MN vs. 21/30, 70% in podocytopathy). Warfarin was the most common agent used in MN cohort 18/26 (69%) versus prophylactic dose low-molecular-weight heparin in the podocytopathy cohort 12/28 (43%). Discussion/Conclusion: PAC practices applied in this cohort of patients were pragmatic and effective, with low TEE rates during active NS.

Thromboembolism in nephrotic syndrome: controversies and uncertainties.

Thromboembolism is one of the most serious complications of nephrotic syndrome, including both arterial and venous thromboembolic events. Rates of thromboembolism depend on a multitude of factors, including the severity and cause of nephrotic syndrome, with primary membranous nephropathy having the highest reported rates. In relation to arterial thromboembolism, the risk can be as high as 8 times that of an age- and sex-matched population. However, extrapolating risks is challenging, with published studies not being homogeneous, several being single center and retrospective, and including different causes of primary nephrotic syndrome. Determining thromboembolic risk in nephrotic syndrome is essential to enable decision making on preventive strategies. However, lack of proven strategies to help estimate risk-benefit aspects underpins variations in clinical practice. Although the use of anticoagulation following a thrombotic event is clear, this still leaves us with a clinical dilemma as to if, and who, should receive prophylactic anticoagulation, with what agent, and for how long. In the absence of clear evidence to answer these questions, prophylactic anticoagulation strategies for nephrotic syndrome currently rely on expert consensus opinion, such as in the recently published 2021 Kidney Disease Improving Global Outcomes glomerular disease guidelines. In the mainstay, these recommendations relate to patients with membranous nephropathy. Here, we detail the current controversies still faced by clinicians around the risk of thromboembolism in nephrotic syndrome, use of prophylactic anticoagulation in nephrotic syndrome and propose ways of advancing existing knowledge and practice in this field to unravel the conundrum.

PLA2R Antibody Does Not Outperform Conventional Clinical Markers in Predicting Outcomes in Membranous Nephropathy.

Introduction: The prognostic value of PLA2R antibody (Ab) test in clinical practice remains unclear. We aimed to evaluate its ability in predicting hard outcomes in primary membranous nephropathy (PMN) after adjustments to conventional markers of disease activity. Methods: A total of 222 patients diagnosed with PMN from January 2003 to July 2019 having had a serum PLA2R Ab test, were included from 3 centers in the north of England. Baseline conventional markers, PLA2R-Ab-status (positive vs. negative), Ab-titer (high vs. low), and time of testing (pre-PLA2R era vs. PLA2R era) were evaluated for association with outcomes. Primary outcome was time to progression (composite of doubling of creatinine, stage 5 chronic kidney disease, or death). Secondary outcomes were time to partial remission (PR) and time to immunosuppression. Cox proportional hazard testing was used. Results: During a median follow-up of 5.26 years, progression was seen in 65 (29.3%) and PR in 179 of 222 patients (80.6%). There was a clear association of estimated glomerular filtration rate (eGFR) (standardized hazard ratio [HRZ] = 0.767, P < 0.05) and urine protein-to-creatinine ratio (uPCR) (HRZ = 1.44, P < 0.005) with time to progression among all patients, and eGFR (HRZ = 0.606, P < 0.005) in Ab-positive patients. Baseline Ab-positivity was not associated with time to progression (adjusted hazard ratio [aHR] = 0.93, P = 0.71) or time to PR (aHR = 0.84, P = 0.13). Similarly, baseline high Ab-titer was not associated with time to progression (aHR = 1.07, P = 0.77) or time to PR (aHR = 0.794, P = 0.08). Conclusion: Once adjusted to conventional markers of disease activity, baseline PLA2R Ab-positivity or Ab-titer do not predict disease progression or time to PR. Further studies are needed to harness the utility of PLA2R Ab test in prognostication in PMN.

Long-Term Safety, Clinical and Immunological Outcomes in Primary Membranous Nephropathy with Severe Renal Impairment Treated with Cyclophosphamide and Steroid-Based Regimen.

Introduction and Aims: Therapy of primary membranous nephropathy (PMN) with progressive advanced kidney dysfunction is challenging with limited literature and no clear therapeutic strategies. This is due to the scant evidence of effectiveness and uncertainty around the risk-benefit profile of immunosuppression (ImS) when eGFR is less than 30 mL/min. We aimed to determine long-term clinical outcomes in patients with PMN and severe renal impairment treated with combined cyclophosphamide and steroids. Methods: The study is a single-center retrospective longitudinal cohort study. All patients (between 2004 and 2019) with biopsy confirmed PMN who initiated combination therapy with steroids and cyclophosphamide and had an eGFR of ≤30 mL/min/1.73 m2 at the time of initiation of therapy were included for analysis. Clinical and laboratory parameters including anti-PLA2R-Ab were monitored as per standard clinical guidance. Primary outcome was achievement of partial remission. Secondary outcomes included immunological remission, need for renal replacement therapy, and adverse effects. Results: Eighteen patients with median age of 68 (IQR 58-73) years and 5:1 M:F ratio received the combination therapy when eGFR was ≤30 mL/min/1.73 m2 (CKD-EPI). At time of ImS, median eGFR and uPCR were 23 (IQR 18-27) mL/min/1.73 m2 and 8.4 (IQR 6.9-10.7) g/g, respectively. Median follow-up was for 67 (IQR 27-80) months. 16 patients (89%) achieved partial remission and 7 (39%) achieved complete remission. eGFR increased by 7 mL/min/1.73 m2 (27%) after 1 year of starting ImS treatment and 12 mL/min/1.73 m2 at end of follow-up. Two patients (11%) developed end-stage renal disease needing renal replacement therapy. 67% achieved both immunological and clinical remission. At the end of the follow-up period, 2 (11%) patients required hospitalization secondary to infections, 4 (22%) patients developed cancer and 4 patients died (22%). Conclusion: Combination therapy with cyclophosphamide and steroids is effective in achieving partial remission and improving renal function in PMN with advanced renal dysfunction. Prospective controlled studies are required to provide further evidence to rationalize treatment and improve outcomes in such patients.

Membranous nephropathy in the UK Biobank.

BACKGROUND: Despite MN being one of the most common causes of nephrotic syndrome worldwide, its biological and environmental determinants are poorly understood in large-part due to it being a rare disease. Making use of the UK Biobank, a unique resource holding a clinical dataset and stored DNA, serum and urine for ~500,000 participants, this study aims to address this gap in understanding. METHODS: The primary outcome was putative MN as defined by ICD-10 codes occurring in the UK Biobank. Univariate relative risk regression modelling was used to assess the associations between the incidence of MN and related phenotypes with sociodemographic, environmental exposures, and previously described increased-risk SNPs. RESULTS: 502,507 patients were included in the study of whom 100 were found to have a putative diagnosis of MN; 36 at baseline and 64 during the follow-up. Prevalence at baseline and last follow-up were 72 and 199 cases/million respectively. At baseline, as expected, the majority of those previously diagnosed with MN had proteinuria, and there was already evidence of proteinuria in patients diagnosed within the first 5 years of follow-up. The highest incidence rate for MN in patients was seen in those homozygous for the high-risk alleles (9.9/100,000 person-years). CONCLUSION: It is feasible to putatively identify patients with MN in the UK Biobank and cases are still accumulating. This study shows the chronicity of disease with proteinuria present years before diagnosis. Genetics plays an important role in disease pathogenesis, with the at-risk group providing a potential population for recall.

Can use of the serum anti-PLA2R antibody negate the need for a renal biopsy in primary membranous nephropathy?

BACKGROUND: Since the emergence of the anti-PLA2R antibody (PLA2R-Ab) test, nephrology practice has not changed dramatically, with most nephrologists still relying on a kidney biopsy to diagnose membranous nephropathy. In this study, we examined the clinical accuracy of the anti-PLA2R antibody test using ELISA in routine clinical care. METHODS: We conducted a retrospective analysis of PLA2R-Ab testing in 187 consecutive patients seen at a single UK centre between 2003 and 2020. We compared the kidney biopsy findings with the PLA2R-ab antibody test. Patients' demography, urine protein creatinine ratios, serum albumin, and treatment characteristics including supportive and immunosuppressive treatment were recorded. The clinical accuracy of the test (e.g. sensitivity and specificity, positive [PPV] and negative [NPV] predictive values) was calculated using the kidney biopsy findings as the diagnostic reference. RESULTS: Mean levels of PLA2R-Ab titre in primary membranous nephropathy were 217RU/ml in comparison to 3RU/ml for both secondary membranous nephropathy and other diagnoses. Most patients with a positive PLA2R-Ab test had a confirmed renal biopsy diagnosis of primary membranous nephropathy with: PPV of 97.3%, sensitivity 75.5%, NPV was 79.8% and specificity was 97.8% at a cut-off threshold of >20 RU/ml. CONCLUSION: The anti-PLA2R antibody test is a highly specific test for diagnosing membranous nephropathy, and the test has the potential to allow for the diagnosis and treatment in up to 75% of PMN cases without the need for a renal biopsy. Nevertheless, patients with negative PLA2R-Ab tests will still require a biopsy to confirm their diagnosis.

Anti-thymocyte globulin for treatment of T-cell-mediated allograft rejection.

Anti-thymocyte globulin (ATG) is a pivotal immunosuppressive therapy utilized in the management of T-cell-mediated rejection and steroid-resistant rejection among renal transplant recipients. Commercially available as Thymoglobulin (rabbit-derived, Sanofi, United States), ATG-Fresenius S (rabbit-derived), and ATGAM (equine-derived, Pfizer, United States), these formulations share a common mechanism of action centered on their interaction with cell surface markers of immune cells, imparting immunosuppressive effects. Although the prevailing mechanism predominantly involves T-cell depletion via the com plement-mediated pathway, alternate mechanisms have been elucidated. Optimal dosing and treatment duration of ATG have exhibited variance across ran domised trials and clinical reports, rendering the establishment of standardized guidelines a challenge. The spectrum of risks associated with ATG administration spans from transient adverse effects such as fever, chills, and skin rash in the acute phase to long-term concerns related to immunosuppression, including susceptibility to infections and malignancies. This comprehensive review aims to provide a thorough exploration of the current understanding of ATG, encom passing its mechanism of action, clinical utility in the treatment of acute renal graft rejections, specifically steroid-resistant cases, efficacy in rejection episode reversal, and a synthesis of findings from different eras of maintenance immunosuppression. Additionally, it delves into the adverse effects associated with ATG therapy and its impact on long-term graft function. Furthermore, the review underscores the existing gaps in evidence, particularly in the context of the Banff classification of rejections, and highlights the challenges faced by clinicians when navigating the available literature to strike the optimal balance between the risks and benefits of ATG utilization in renal transplantation.

Renal sarcoidosis associated with certolizumab pegol treatment for psoriatic arthritis.

We present a case of certolizumab-associated renal sarcoidosis, the first reported case in a patient with psoriatic arthritis (PsA) that was effectively treated with corticosteroids. A 55-year-old Caucasian man with PsA diagnosed at age 47 and plaque psoriasis since his early twenties was on certolizumab pegol (CZP) for 7 months before presenting to the emergency department with seizures and renal failure. A renal biopsy confirmed renal sarcoidosis. His CZP therapy was stopped, and after several months taking prednisolone at a reducing regime, his renal function improved, and his PsA remained under control. When considering further treatment options for his PsA keeping in mind that other drugs, especially tumour necrosis factor-alpha inhibitors, have been reported to be associated with sarcoidosis, tofacitinib was considered to be a future treatment option acceptable to the patient, given current National Institute for Health and Care Excellence guidelines approving its use in PsA and the lack of reports of tofacitinib-associated sarcoidosis in the literature.

Peptide GAM immunoadsorption in anti-PLA2 R positive autoimmune membranous nephropathy. The PRISM trial.

Membranous nephropathy associated with anti-PLA2 R autoantibody is a significant cause of nephrotic syndrome worldwide. Treatment remains empiric with a significant side-effect burden despite an increase in our understanding of the disease. We studied the effect of selectively removing this pathogenic autoantibody using immunoadsorption in adult patients with biopsy proven anti-PLA2 R membranous nephropathy. This was a multicenter, single-arm prospective clinical trial carried out in the United Kingdom. Twelve patients underwent five consecutive sessions of peptide GAM immunoadsorption with 12 months follow-up. Primary outcome was anti-PLA2 R titer at week 2. Secondary outcomes were safety and tolerability of therapy, antibody profile, and change in proteinuria, renal excretory function, serum albumin, total immunoglobulin, and quality of life at weeks 12, 24, and 52. Patients were also stratified by the presence or absence of the high-risk allele (heterozygous or homozygous for HLA-DQA1*05). Median pretreatment anti-PLA2 R was 702.50 U/mL, 1045.00 U/mL at week 2 (P-value .023) and 165.00 U/mL at week 52 (P-value .017). The treatment was well tolerated and safe. Two patients required rescue immunosuppression during the follow-up period. There was a significant improvement in serum albumin with a median at baseline of 20.50 g/L rising to 25.00 g/L at week 52 (P-value <.001). There was no statistical difference over the follow-up period in proteinuria or renal function. Patients in possession of a high-risk allele saw improvement in anti-PLA2 R titers, possibly representing a cohort more likely to benefit from immunoadsorption. Immunoadsorption therapy is a safe treatment and well-tolerated treatment in anti-PLA2 R positive autoimmune membranous nephropathy.

A Case of IgG4-Related Disease and Membranous Nephropathy Associated with Thrombospondin Type-1 Domain-Containing 7A.

Background: IgG4-related disease (IgG4-RD) is a systemic multi-organ inflammatory disorder which affects the kidney 20% of the time. Patients with intrinsic IgG4-related kidney disease (IgG4-RKD) often have tubulointerstitial nephritis (TIN) whereas glomerular lesions like membranous nephropathy (MN) are less common. Antibodies to thrombospondin type-1 domain-containing 7A (THSD7A) have been described in primary MN, but never in association with IgG4-RKD. Case Report: We report the first case of IgG4-MN associated with THSD7A antibodies in serum and positivity on glomerular staining, in a 57-year-old Caucasian male with IgG4-RD affecting the pancreas, liver, lacrimal glands, extraocular muscles, and kidneys. This patient presented initially with glomerular disease including significant proteinuria consistent with MN. Glomerular staining for THSD7A antigen and serum THSD7A antibody titres was positive. Treatment with corticosteroids and cyclophosphamide successfully induced remission with resolution of proteinuria, and improvement in renal function. However, despite maintenance azathioprine, the patient relapsed 39 months later. On relapse, there was minimal proteinuria but a significant rise in creatinine. Subsequent renal biopsy showed less glomerular disease and instead a TIN pattern. Subsequent treatment with Rituximab and corticosteroids successfully induced remission. Conclusion: The role of THSD7A autoantibodies in MN is emerging, and as both IgG4-MN and presence of THSD7A antibody are rare occurrences in themselves, we speculate that there may be an undiscovered association between THSD7A and IgG4-MN. Routine testing for THSD7A in IgG4-MN may help to identify the link.

Non-invasive cardiac stress studies may not offer significant benefit in pre-kidney transplant evaluation: A retrospective cohort study.

BACKGROUND: Screening with cardiac non-invasive stress studies (NISS) prior to listing for kidney transplantation can help in identifying treatable coronary disease and is considered an integral part of pre-kidney transplant evaluation. However, few studies assessed their effectiveness in all patients evaluated for transplantation in clinical practice. To evaluate the role of NISS in pre-kidney transplant evaluation we analyzed their impact prior to waitlisting in 1053 adult CKD-5 patients consecutively evaluated in Greater Manchester, UK during a 6-year period. METHODS: 918 waitlisted patients were grouped based on presence or absence of Diabetes or Cardio-Vascular Disease (CVD): Group-1 (255 DM-/CVD-/NISS-), Group-2 (368 DM-/CVD-/NISS+) and Group-3 (295 with DM or CVD). RESULTS: Group-2 patients had longer 'time-to-listing' (5.5months in Group-1 vs 6.9months in 'Normal-NISS' vs 9.9months in 'Abnormal-NISS', p<0.01) but none with 'Abnormal-NISS' needed coronary revascularization before listing. NISS was followed by revascularization in 8 Group-3 patients (3%). In multi-variate analyses, there was no association of NISS on death or MACE in listed patients. During follow up, Transplantation was the most significant factor associated with improved outcomes in all subgroups (HR:0.97, p<0.001). 135 patients were considered unsuitable for waitlisting, with NISS influencing management in 11 of these patients (8%). CONCLUSIONS: Pre-kidney transplant evaluation with NISS influenced clinical management in 19 of 1053 (2%) patients. Screening with NISS added limited benefit but contributes to significant delays in listing and adding resource implications. Further studies are needed to assess clinical and cost effectiveness of NISS in pretransplant evaluation to optimize outcomes and resources.

The investigative burden of membranous nephropathy in the UK.

BACKGROUND: Membranous nephropathy (MN) represents two distinct disease entities. Primary MN is now recognized as an autoimmune condition associated with the anti-PLA2R antibody and secondary MN occurs in tandem with malignancy, infection, drug therapy and other autoimmune conditions. Prior to the development of accessible enzyme-linked immunosorbent assays, the diagnosis of MN was one of exclusion. We studied whether the introduction of serum anti-PLA2R antibody testing leads to a reduction in the frequency of investigations in MN patients. METHODS: Patients from three UK centres with a diagnosis of MN between 2009 and 2014 were identified. We compared patients who had a positive anti-PLA2R test within 6 months of biopsy with those who had no test or a negative test. Records were reviewed for investigations that took place 6 months prior to and 6 months following the biopsy date to see if these were normal or identified a secondary cause of MN. RESULTS: In total, 184 patients were included: 80 had no test, 66 had a negative anti-PLA2R test and 38 had a positive test within 6 months of diagnosis. In 2012, 46.5% of patients had an anti-PLA2R test, increasing to 93.3% in 2014. From 2012 to 2014 the number of screening tests dropped from 10.03 to 4.29 and the costs from £497.92 to £132.94. CONCLUSIONS: Since its introduction, a progressively higher proportion of patients diagnosed with MN had an anti-PLA2R test. This has led to a reduction in the number of screening tests and in the cost of investigations carried out. The anti-PLA2R test has the potential to reduce this burden as its use becomes more widespread.

Rituximab versus the modified Ponticelli regimen in the treatment of primary membranous nephropathy: a Health Economic Model.

Background: Membranous nephropathy is among the most common causes of nephrotic syndrome worldwide, with a high healthcare burden. Treatment using the modified Ponticelli regimen (mPR) has remained the standard of care for decades, but newer therapies such as rituximab offer promising results with reduced side effects. The cost of this treatment, however, is perceived as a barrier to widespread use, especially in resource limited healthcare systems. Methods: We developed a decision-analytic model to estimate the cost-effectiveness of rituximab versus the mPR from the perspective of the National Health Service in the UK over a 1 year, 5 year and lifetime horizon. Primary outcome is the cost-effectiveness of rituximab versus mPR at 5 years post-treatment. Secondary outcomes are cost-effectiveness at 1 and 10 years post-treatment and over a lifetime. Results: At 1-year post-treatment, rituximab therapy dominates mPR. At 5 years post-treatment, rituximab therapy is cheaper than the Ponticelli regimen but at a loss of 0.014 quality-adjusted life years (QALYs) with an incremental cost-effectiveness ratio (ICER) of £95 494.13. Over a lifetime, rituximab remains the cheaper option with an incremental cost of -£5251.03 but with a reduced quality of life (incremental QALY of -0.512) giving an ICER of £10 246.09. Conclusions: Our analysis indicates that rituximab has the potential to be a cost-effective treatment in the short and medium terms despite the high single-dose cost. This evaluation suggests that further research is warranted and highlights the need for a high-quality clinical trial to confirm the efficacy and cost-effectiveness of rituximab versus the current standard of care.

Intravenous pulse cyclophosphamide and steroids induce immunological and clinical remission in New-incident and relapsing primary membranous nephropathy.

AIM: Primary membranous nephropathy is associated with progression to end stage renal diseasein some patients. Standard therapy with cyclical cyclophosphamide and corticosteroids can be associated with significant adverse effects. We aimed to assess immunological and clinical response with intravenous pulse cyclophosphamide and oral steroids in patients with severe nephrotic syndrome - in a prospective observational cohort study. METHODS: A total of 17 consecutive patients (nine new-incident and eight relapses) with severe nephrotic syndrome received monthly intravenous pulse cyclophosphamide and oral steroids after failure to achieve remission with supportive therapy. Immunosuppressive therapy was discontinued at 6 months or earlier if proteinuria regressed to <100 mg/mmol and patients were followed for 12 months. Achievement of partial remission was primary outcome; changes in clinical parameters and anti-PLA2 R were secondary outcomes. RESULTS: Dose of cyclophosphamide received was 5.4 g in New-incident patients and 4.2 g in patients with relapses. All 17 patients achieved partial remission within 6 months: proteinuria improved from 656 to 102 mg/mmol at 6 months and 55 mg/mmol at 12 months (P < 0.001); eGFR improved from 31 to 48 mL/min per 1.73 m2 at 6 months and 45 mL/min per 1.73 m2 at 12 months (P < 0.05). Anti-PLA2 R levels reduced from 244 to 10 U/L at 6 months and 10 U/L at 12 months (P < 0.001). Two out of nine patients in the New-incident group developed subsequent relapse. Cumulative doses of cyclophosphamide and steroids that patients received was about half of the standard regime. CONCLUSION: Pulse cyclophosphamide with oral steroids induced immunological and clinical partial remission at significantly reduced doses in primary membranous nephropathy.

Peptide GAM immunoadsorption therapy in primary membranous nephropathy (PRISM): Phase II trial investigating the safety and feasibility of peptide GAM immunoadsorption in anti-PLA2 R positive primary membranous nephropathy.

INTRODUCTION: Membranous nephropathy (MN) is among the most common causes of nephrotic syndrome in adults worldwide. Most patients have primary MN (PMN), an autoimmune condition associated with the IgG anti-PLA2 R autoantibody. For patients with severe disease, standard of care continues to be a 6-month regime of rotating high dose steroids and immunosuppression that comes with a significant side-effect profile. Immunoadsorption is a relatively safe procedure for the extracorporeal removal of specific immunoglobulins without the need for medications. DESIGN: This is a Phase II multi-centre, single arm prospective clinical trial carried out across Northwest region of the United Kingdom to assess the safety and clinical effectiveness of immunoadsorption therapy in PMN. 12 adult patients with biopsy proven MN, nephrotic range proteinuria and serum anti-PLA2 R antibody titers of more than 170 µ/mL will undergo 5 consecutive daily sessions of immunoadsorption. Primary outcome is the reduction of serum anti-PLA2 R antibodies at day 14. Secondary outcomes are the safety and tolerability of immunoadsorption therapy in patients with primary MN at all-time points, reduction of serum anti-PLA2 R levels, proteinuria and improvement in renal function. Quality of life and Cost-effectiveness of treatment will be assessed from a UK National Health Service perspective. DISCUSSION: With proven efficacy in removing IgG antibodies and its use as a relatively safe treatment option in a multitude of conditions, immunoadsorption has the potential to offer patients with primary MN a more directed therapy free from the short and long-term side-effects generally seen in this condition.

Long-term outcomes of persistent disease and relapse in primary membranous nephropathy.

BACKGROUND: Primary membranous nephropathy is associated with variable clinical course ranging from spontaneous remission to slow progression to end stage renal failure. Achieving remission confers better renal survival in primary membranous nephropathy (PMN). Longer term outcomes such as patient survival and relapse of active disease remain poorly understood. METHODS: We performed a retrospective study of 128 consecutive adult patients diagnosed with biopsy proven PMN at a single UK centre between 1980 and 2010. These patients were followed prospectively over a median of 128 months. We assessed impact of persistent disease and relapse on Stage 5 chronic kidney disease (CKD-5) and patient survival and present longer term cumulative incidences of different end points. RESULTS: One hundred patients achieved partial remission (PartRem) and 28 patients did not achieve remission (NoRem). Nine per cent of patients achieving first remission developed CKD-5 and 75% of those with NoRem developed CKD-5 [hazard ratio (HR) 0.07, 95% confidence interval 0.03-0.19). Relapse following PartRem occurred in 31 patients (31%) during follow-up and was significantly associated with progression to CKD-5. Progression to CKD-5 was strongly associated with death (47 versus 6%, HR 23.4; P < 0.01). Cumulative incidence at 15 years following first presentation included: death, 14%; CKD-5, 28%; and relapse 40% (in patients who achieved first remission). CONCLUSIONS: Our data strongly suggest that mortality in PMN is seen in patients with disease progression to CKD-5. Achieving remission is strongly associated with improved renal survival after first presentation and following relapse. We suggest that patients who achieve remission should be followed up in longer term, and better strategies to help improve outcomes are needed in clinical practice.

Hepatitis e infection in a renal transplant recipient.

An asymptomatic 35-year-old renal transplant recipient was noted to have deranged liver function tests. Liver biopsy revealed a portal inflammatory process with mild lobular activity and portal fibrous expansion, consistent with a virally mediated process. An extensive viral screen confirmed infection with Hepatitis E virus genotype 3 (HEV-3). There is increased awareness about locally acquired Hepatitis E virus (HEV) infection in the transplant population in the UK. The important implications of this infection are becoming more apparent as progression to liver cirrhosis can occur. However, the incidence, natural history, and treatment of HEV infection in the transplant population are not well established. This report illustrates a case of delayed spontaneous clearance of the HEV infection.

Anti-PLA2R antibodies measured by ELISA predict long-term outcome in a prevalent population of patients with idiopathic membranous nephropathy.

Antibodies to the phospholipase A2 receptor 1 (PLA2R1) have been reported in 70% of cases of idiopathic membranous nephropathy (IMN). The genetic susceptibility of IMN has been accounted for by HLA DQA1 and PLA2R1 genes. Here we retrospectively quantified PLA2R antibodies by ELISA, and genotyped DQ alleles and PLA2R1 single-nucleotide polymorphisms for association with clinical criteria for disease activity at the time of first sample and with outcome over a median total follow-up of 90 months. In 90 prevalent patients with biopsy-proven IMN, anti-PLA2R antibodies were present in 75% of patients with IMN with active disease and were significantly higher than in patients in partial or complete remission at the time of antibody measurement. There was a differential IgG subclass response (4>2>3>1) at an early stage, i.e., within 6 months of biopsy. Levels of PLA2R antibodies were significantly linked to DQA1*05:01 and DQB1*02:01. Survival analysis of patients with IMN showed that PLA2R antibodies are significantly linked with outcome. Thus, high levels of PLA2R antibodies are linked with active disease and a higher risk of declining renal function during follow-up. Future therapeutic trials in IMN should monitor anti-PLA2R, as patients with a high antibody burden may benefit from earlier therapeutic intervention.