High grade urothelial carcinoma in kidney transplant patients with a history of BK viremia - Just a coincidence?

INTRODUCTION: Kidney transplant recipients (KTR) have a three-to-four-fold increased risk of developing urothelial carcinoma (UC) compared to the general population. BK polyoma virus (BKV) infection is known to affect approximately 15% of KTR. In vitro models support a potential pathogenic role for BKV in the development of UC. We describe a series of UC in kidney transplant recipients. METHODS: Electronic patient records were searched to identify KTR with UC who had undergone kidney only or simultaneous kidney and pancreas transplantation in a single UK center between 2009 and 2015. Where available, stored pathological samples were retrieved, re-examined and stained for SV40 as a marker of BKV using standard staining protocols for kidney biopsy samples. RESULTS: Fourteen KTR had developed UC post-transplant. Of these, 10 KTR had a history of BKV infection post-transplant. Six of these 10 KTR developed a rare micropapillary tumor subtype of UC which is typically only found in <1% of UC cases. All six micropapillary tumor samples stained positive for SV40, including samples from metastases. Three tumor samples were available from the four KTR with no history of BKV infection and were not micropapillary subtype and were negative for SV40. Three micropapillary tumors from immunocompetent patients were examined as controls and were negative for SV40. CONCLUSIONS: These findings would support a pathogenic role for BK virus in the development of rare micropapillary subtype urothelial tumors in the kidney transplant population.

Outcomes in ANCA-Associated Vasculitis in Scotland: Validation of the Renal Risk Score in a Complete National Cohort.

Introduction: Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) causes autoimmune-mediated inflammation of small blood vessels in multiple organs, including the kidneys. The ability to accurately predict kidney outcomes would enable a more personalized therapeutic approach. Methods: We used our national renal biopsy registry to validate the ability of ANCA Renal Risk Score (ARRS) to predict end-stage kidney disease (ESKD) for individual patients. This score uses histopathological and biochemical data to stratify patients as high, medium, or low risk for developing ESKD. Results: A total of 288 patients were eligible for inclusion in the study (low risk n = 144, medium risk n = 122, high risk n = 12). Using adjusted Cox proportional hazard models with the low-risk group as reference, we show that outcome differs between the categories: high-risk hazard ratio (HR) 16.69 (2.91-95.81, P = 0.002); medium risk HR 4.14 (1.07-16.01, P = 0.039). Incremental multivariable-adjusted Cox proportional hazards models demonstrated that adding ARRS to a model adjusted for multiple clinical parameters enhanced predictive discrimination (basic model C-statistic 0.864 [95% CI 0.813-0.914], basic model plus ARRS C-statistic 0.877 [95% CI 0.823-0.931]; P <0.01). Conclusion: The ARRS better discriminates risk of ESKD in AAV and offers clinicians more prognostic information than the use of standard biochemical and clinical measures alone. This is the first time the ARRS has been validated in a national cohort. The proportion of patients with high-risk scores is lower in our cohort compared to others and should be noted as a limitation of this study.

Incidence and Outcomes of Patients Receiving Chronic Kidney Replacement Therapy Admitted to Scottish ICUs Between 2009 and 2019-A National Observational Cohort Study.

OBJECTIVES: To determine the incidence and characteristics of ICU admissions in the Scottish population of patients treated with chronic kidney replacement therapy (KRT) over an 11-year period and determine factors associated with post-ICU admission mortality. DESIGN: Retrospective observational cohort study. SETTING: We analyzed admissions to Scottish intensive care environments between January 1, 2009, and December 31, 2019. PATIENTS: All patients receiving chronic KRT-including maintenance dialysis and kidney transplant-in Scotland. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Descriptive statistics and factors associated with mortality using logistic regression and Cox proportional hazard models. From 10,657 unique individuals registered in the Scottish Renal Registry over the 11-year study period and alive as of January 1, 2009, 1,402 adult patients were identified as being admitted to a Scottish critical care setting. Between 2009 and 2019, admissions to ICU increased in a nonlinear manner driven by increases in admissions for renal causes and elective cardiac surgery. The ICU admission rate was higher among patients on chronic dialysis than in kidney transplant recipients (59.1 vs 19.9 per 1,000 person-years), but post-ICU mortality was similar (about 24% at 30 d and 40% at 1 year). Admissions for renal reasons were most common (20.9%) in patients undergoing chronic dialysis, whereas kidney transplant recipients were most frequently admitted for pneumonia (19.3%) or sepsis (12.8%). Adjusted Cox PH models showed that receiving invasive ventilation and vasoactive drugs was associated with an increased risk of death at 30 days post-ICU admission (HR, 1.75; 95% CI, 1.28-2.39 and 1.72; 95% CI, 1.28-2.31, respectively). CONCLUSIONS: With a growing population of kidney transplant recipients and the improved survival of patients on chronic dialysis, the number of ICU admissions is rising in the chronic KRT population. Mortality post-ICU admission is high for these patients.

The Impact of Vaccination on Incidence and Outcomes of SARS-CoV-2 Infection in Patients with Kidney Failure in Scotland.

BACKGROUND: Patients with kidney failure requiring KRT are at high risk of complications and death following SARS-CoV-2 infection, with variable antibody responses to vaccination reported. We investigated the effects of COVID-19 vaccination on the incidence of infection, hospitalization, and death from COVID-19 infection. METHODS: The study design was an observational data linkage cohort study. Multiple health care datasets were linked to ascertain all SARS-CoV-2 testing, vaccination, hospitalization, and mortality data for all patients treated with KRT in Scotland from the start of the pandemic over a period of 20 months. Descriptive statistics, survival analyses, and vaccine effectiveness were calculated. RESULTS: As of September 19, 2021, 93% (n=5281) of the established KRT population in Scotland had received two doses of an approved SARS-CoV-2 vaccine. Over the study period, there were 814 cases of SARS-CoV-2 infection (15.1% of the KRT population). Vaccine effectiveness rates against infection and hospitalization were 33% (95% CI, 0 to 52) and 38% (95% CI, 0 to 57), respectively. Within 28 days of a SARS-CoV-2-positive PCR test, 9.2% of fully vaccinated individuals died (7% patients on dialysis and 10% kidney transplant recipients). This compares to <0.1% of the vaccinated general Scottish population admitted to the hospital or dying due to COVID-19 during that period. CONCLUSIONS: These data demonstrate that a primary vaccine course of two doses has limited effect on COVID-19 infection and its complications in patients with KRT. Adjunctive strategies to reduce risk of both COVID-19 infection and its complications in this population are urgently required.

ANCA-associated renal vasculitis is associated with rurality but not seasonality or deprivation in a complete national cohort study.

BACKGROUND: Small studies suggest an association between ANCA-associated vasculitis (AAV) incidence and rurality, seasonality and socioeconomic deprivation. We examined the incidence of kidney biopsy-proven AAV and its relationship with these factors in the adult Scottish population. METHODS: Using the Scottish Renal Biopsy Registry, all adult native kidney biopsies performed between 2014 and 2018 with a diagnosis of granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA) were identified. The Scottish Government Urban Rural Classification was used for rurality analysis. Seasons were defined as autumn (September-November), winter (December-February), spring (March-May) and summer (June-August). Patients were separated into quintiles of socioeconomic deprivation using the validated Scottish Index of Multiple Deprivation and incidence standardised to age. Estimated glomerular filtration rate and urine protein:creatinine ratio at time of biopsy were used to assess disease severity. RESULTS: 339 cases of renal AAV were identified, of which 62% had MPA and 38% had GPA diagnosis. AAV incidence was 15.1 per million population per year (pmp/year). Mean age was 66 years and 54% were female. Incidence of GPA (but not MPA) was positively associated with rurality (5.2, 8.4 and 9.1 pmp/year in 'urban', 'accessible remote' and 'rural remote' areas, respectively; p=0.04). The age-standardised incidence ratio was similar across all quintiles of deprivation (p=ns). CONCLUSIONS: Seasonality and disease severity did not vary across AAV study groups. In this complete national cohort study, we observed a positive association between kidney biopsy-proven GPA and rurality.

A National Registry Study of Patient and Renal Survival in Adult Nephrotic Syndrome.

INTRODUCTION: We aimed to determine the mortality rate, cause of death, and rate of end-stage kidney disease (ESKD) in adults with nephrotic syndrome (NS). METHODS: We conducted a national registry-based study, including all 522 adults who had a kidney biopsy for NS in Scotland in 2014-2017. We linked the Scottish Renal Registry to death certificate data. We performed survival and Cox proportional hazards analyses, accounting for competing risks of death and ESKD. We compared mortality rates with those in the age- and sex-matched general population. RESULTS: A total of 372 patients had primary NS; 150 had secondary NS. Over a median follow-up of 866 days, 110 patients (21%) died. In patients with primary NS, observed versus population 3-year mortality was 2.1% (95% CI 0.0%-4.6%) versus 0.9% (0.8%-1.0%) in patients aged <60 years and 24.9% (18.4%-30.8%) versus 9.4% (8.3%-10.5%) in those aged ≥60 years. In secondary NS, this discrepancy was 17.1% (5.6%-27.2%) versus 1.1% (0.9%-1.2%) in <60-year-olds and 49.4% (36.6%-59.7%) versus 8.1% (6.6%-9.6%) in ≥60-year-olds. In primary NS, cardiovascular causes accounted for 28% of deaths, compared with 18% in the general population. Eighty patients (15%) progressed to ESKD. Incidence of ESKD by 3 years was 8.4% (95% CI 4.9%-11.7%) in primary and 35.1% (24.3%-44.5%) in secondary NS. Early remission of proteinuria and the absence of early acute kidney injury (AKI) were associated with lower rates of death and ESKD. CONCLUSIONS: Adults with NS have high rates of death and ESKD. Cardiovascular causes account for excess mortality in primary NS.

The impact of age on patient tolerance of mycophenolate following kidney transplantation.

BACKGROUND: In Scotland, standard maintenance immunosuppression following kidney transplantation consists of mycophenolate (MPA), tacrolimus and prednisolone irrespective of recipient age. We analyzed the tolerability of this immunosuppression regimen and the association with transplant outcomes. METHODS: A national, multicentre retrospective analysis of patients transplanted in 2015 and 2016, comparing graft function, acute rejection, significant infection rates and immunosuppression dosing between patients aged 18 and 59 years (Group 1) and ≥60 years (Group 2). RESULTS: Of the 490 patients, 26% were aged ≥60 years. Acute rejection (AR) rates at 1 year were 15% and 11% in Groups 1 and 2, respectively. Full-dose MPA was poorly tolerated with 53% in Group 1 and 77% in Group 2 requiring dose reduction or cessation. Female gender and age ≥60 years were independent predictors for MPA dose changes. One year following MPA dose reduction, AR risk was low (5%) in Group 2, however, those remaining on full dose MPA had a 79% increased rate of serious infections. CONCLUSION: The majority of renal transplant recipients aged ≥60 fail to tolerate full-dose MPA. In this group, MPA dose reduction is associated with low rejection rates, but full-dose MPA is associated with high infection rates. We suggest that a tailored approach to immunosuppression in elderly recipients incorporating lower doses of MPA may be appropriate.

Estimated life expectancy in a Scottish cohort with type 1 diabetes, 2008-2010.

IMPORTANCE: Type 1 diabetes has historically been associated with a significant reduction in life expectancy. Major advances in treatment of type 1 diabetes have occurred in the past 3 decades. Contemporary estimates of the effect of type 1 diabetes on life expectancy are needed. OBJECTIVE: To examine current life expectancy in people with and without type 1 diabetes in Scotland. We also examined whether any loss of life expectancy in patients with type 1 diabetes is confined to those who develop kidney disease. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort of all individuals alive in Scotland with type 1 diabetes who were aged 20 years or older from 2008 through 2010 and were in a nationwide register (n=24,691 contributing 67,712 person-years and 1043 deaths). MAIN OUTCOMES AND MEASURES: Differences in life expectancy between those with and those without type 1 diabetes and the percentage of the difference due to various causes. RESULTS: Life expectancy at an attained age of 20 years was an additional 46.2 years among men with type 1 diabetes and 57.3 years among men without it, an estimated loss in life expectancy with diabetes of 11.1 years (95% CI, 10.1-12.1). Life expectancy from age 20 years was an additional 48.1 years among women with type 1 diabetes and 61.0 years among women without it, an estimated loss with diabetes of 12.9 years (95% CI, 11.7-14.1). Even among those with type 1 diabetes with an estimated glomerular filtration rate of 90 mL/min/1.73 m2 or higher, life expectancy was reduced (49.0 years in men, 53.1 years in women) giving an estimated loss from age 20 years of 8.3 years (95% CI, 6.5-10.1) for men and 7.9 years (95% CI, 5.5-10.3) for women. Overall, the largest percentage of the estimated loss in life expectancy was related to ischemic heart disease (36% in men, 31% in women) but death from diabetic coma or ketoacidosis was associated with the largest percentage of the estimated loss occurring before age 50 years (29.4% in men, 21.7% in women). CONCLUSIONS AND RELEVANCE: Estimated life expectancy for patients with type 1 diabetes in Scotland based on data from 2008 through 2010 indicated an estimated loss of life expectancy at age 20 years of approximately 11 years for men and 13 years for women compared with the general population without type 1 diabetes.

Steroid-responsive polyradiculopathy in association with focal segmental glomerulosclerosis.

An 80-year-old woman presented with simultaneous increasing muscle weakness and nephrotic syndrome. A renal biopsy confirmed focal segmental glomerulosclerosis (FSGS). Her neurological diagnosis best fitted with a Guillain-Barre-like syndrome. There have been several cases of FSGS in combination with both conventional and atypical Guillain-Barre syndrome (GBS). Our patient was treated with high-dose steroids and resolution of both nephrotic syndrome and neurological symptoms occurred over 6 months. This article reviews all previously published presentations of this nature and discusses putative mechanisms for the development of concurrent FSGS and GBS.

Granulomatous interstitial nephritis.

Granulomatous interstitial nephritis (GIN) is a rare histologic diagnosis. This series reports the presenting features, associated conditions, treatment, and outcome of patients with a diagnosis of GIN in Glasgow during a 15-yr period and compares this with the available literature. Eighteen cases were identified: Five cases were associated with sarcoidosis, two were associated with tubulointerstitial nephritis and uveitis, two were associated with medication, and nine were idiopathic. Patients presented with advanced renal failure (median estimated creatinine clearance 21 ml/min) and minimal proteinuria (urine albumin-to-creatinine ratio 9.9 mg/mmol). Sixteen patients were treated with prednisolone for a mean of 25 mo. Six patients relapsed with reduction in prednisolone dosage, and four patients required steroid-sparing agents. During the mean follow-up of 45 mo, renal function improved or stabilized in 17 patients; the rate of improvement in renal function was most marked in the first year after diagnosis with a gain in function of +1.9 ml/min per mo. The median estimated creatinine clearance at final visit was 56 ml/min. One patient required renal replacement therapy at diagnosis but recovered renal function with treatment. No patient required long-term renal replacement therapy. There was no correlation between the degree of fibrosis or inflammation on biopsy and renal outcome, and the features on biopsy did not help to determine the cause of GIN. GIN is a treatable cause of renal failure that highlights the value of renal biopsy in patients who present with renal failure even when there is minimal proteinuria. The rarity of GIN demonstrates the need for systematic data collection.

Randomized study comparing cyclosporine with azathioprine one year after renal transplantation-15-year outcome data.

BACKGROUND: The introduction of cyclosporine (CsA) improved 1-year graft survival and reduced the incidence of acute rejection episodes after renal transplantation compared to azathioprine (Aza). However, CsA has many side effects and reducing exposure of this drug after the first year may benefit long-term patient and graft survival. METHODS: We report 15-year outcome data from a single center, randomized controlled study comparing CsA withdrawal and conversion to Aza with continuation of CsA 1-year posttransplant. RESULTS: Two hundred sixteen patients who showed a serum creatinine less than 300 mumol/L with no acute rejection episodes in the preceding 6 months were enrolled (CsA 114, Aza 102). There was no difference in patient survival at 15 years: 62.4% in the CsA group and 64.4% in the Aza group (P=0.6). Fifteen-year transplant survival was 41.9% for the CsA group and 48.8% for the Aza group (P=0.8). Fifteen-year graft survival censoring for death with a functioning graft was 58% in the CsA group and 72% in the Aza group (P=0.5). Predictors of patient survival were younger recipient age (P<0.001) and lower systolic blood pressure at randomization (P=0.01). Predictors of graft survival were older recipient age (P<0.001) and better renal function at randomization (P=0.01). Assigned drug showed no effect on graft or patient survival. Patients assigned to CsA showed significantly worse renal function up to 10 years posttransplantation and required more anti-hypertensive treatment throughout the study period. CONCLUSION: In a selected group of patients, either Aza or low-dose CsA is safe and effective. Despite lower estimated glomerular filtration rate (eGFR) up to 10 years posttransplantation and increased use of anti-hypertensive agents, low-dose CsA was not associated with a worse patient or graft survival.

Predictors of new onset diabetes after renal transplantation.

The development of new onset diabetes after transplantation (NODAT) is associated with increased cardiovascular morbidity and mortality. This study aimed at identifying risk factors for the development of NODAT. We performed a retrospective review of 787 renal transplants performed between 1994 and 2004 at a single centre. NODAT was diagnosed in patients who had two random plasma glucose concentrations >11.1 mmol/L after the first month post-transplant or patients who required treatment for hyperglycaemia within the first month and continued treatment thereafter. The incidence of NODAT was 7.7%. The incidence of NODAT requiring either insulin or oral hypoglycaemic agents was 4.5%. Risk factors for the development of NODAT were older age (HR 1.04, 95% CI: 1.01-1.07, p < 0.01), heavier weight at time of transplantation (HR 1.04, 95% CI: 1.02-1.07, p < 0.01), higher mean pre-transplant random plasma glucose concentrations (HR 1.54, 95% CI: 1.14-2.08, p < 0.01), higher plasma glucose within the first seven d post-transplant (HR 1.27, 95% CI: 1.09-1.47, p < 0.01) and use of tacrolimus (HR 3.70, 95% CI: 1.61-8.46, p < 0.01). Ten yr actuarial patient survival was 67.1% in patients with NODAT compared with 81.9% for those without diabetes and 65.3% in patients known to have diabetes pre-transplant. There was no difference in graft survival. We have identified a high-risk group in which attempts should be made to reduce the incidence of NODAT by tailoring immunosuppression, lifestyle modification and selecting non-diabetogenic medications. Improvements in management of patients at higher risk of NODAT may help reduce the incidence of deaths with a functioning graft.

Influence of apolipoprotein E genotype on progression of diabetic nephropathy.

AIMS: Diabetic nephropathy progresses at a variable rate part of which may be explained by genetic polymorphisms. ApoE polymorphisms are associated with progression of atherosclerosis and because of the similarities between atherosclerosis and glomerulosclerosis, we chose to examine apoE and its role in progression of diabetic nephropathy. METHODS: The apoE genotypes of 90 patients with type 2 diabetes and nephropathy who were recruited into a 2-year prospective randomised controlled study comparing intensive medical management with routine clinical care were analysed. The primary endpoint was the rate of progression of renal disease in the second year. RESULTS: The apoE genotype frequencies were 49 with E3/3, 20 with E2/3, 17 with E3/4 and 4 with of E2/4. There were no significant differences in age, degree of renal failure, BP, albuminuria or glycaemic control between any genotype. The rate of progression of renal failure of patients with the E3/4 genotype was 0.80 ml/min/month compared to 0.30 ml/min/month for E2/3 and 0.18 ml/min/month for those with E3/3. Patients with E3/4 genotype had significantly faster rates of progression in the second year when compared with the other 3 genotypes (0.80 vs. 0.25 ml/min/month, p = 0.012). There was no difference in mortality according to apoE genotype. CONCLUSION: Patients who possess the apoE3/4 genotype had significantly faster rates of progression of renal failure.