Adrenal insufficiency is common amongst kidney transplant recipients receiving maintenance prednisolone and can be predicted using morning cortisol.

BACKGROUND: Long-term glucocorticoid therapy is a key component of immunosuppression for kidney transplant recipients (KTRs), leading to significant cumulative glucocorticoid exposure. The aims of this study are to investigate the prevalence of adrenal insufficiency (AI) in KTRs taking prednisolone and to develop a screening algorithm to identify patients at the highest risk of AI. METHODS: In this cross-sectional cohort study, 67 KTRs receiving prednisolone underwent a short synacthen test (SST) and measurement of cumulative glucocorticoid exposure. RESULTS: A total of 72% (n = 48) of participants failed the SST. Participants with AI had a higher daily prednisolone dose (4.9 versus 4.2 mg/day; P = .002) and greater cumulative glucocorticoid exposure (289 versus 111 mg/kg; P = .03) than those with intact adrenal function. Participants with AI had lower baseline cortisol than participants with intact adrenal function (143 versus 303 nmol/L; P < .001). Morning cortisol of >288 nmol/L predicted a normal SST with 100% specificity [95% confidence interval (CI) 92-100] and 70% sensitivity (95% CI 56-78%), therefore excluding AI. CONCLUSIONS: Our results suggest KTRs are at a higher risk for AI than previously reported. A morning serum cortisol measurement is a useful screening tool in this cohort, reducing the need for stimulatory testing by 44%. KTRs with AI need education regarding glucocorticoid sick rules, similar to patients with other forms of AI.

Would hemodialysis patients benefit from a Staphylococcus aureus vaccine?

Staphylococcus aureus bloodstream infection can have potentially catastrophic consequences for patients on hemodialysis. Consequently, an effective vaccine to prevent S aureus infection would have a significant influence on morbidity and mortality in this group. To date, however, efforts to develop a vaccine have been unsuccessful. Previous antibody-inducing vaccine candidates did not prevent or attenuate S aureus infection in clinical trials. Recent advances have helped to elucidate the role of specific T-cell subsets, notably T-helper cell 1 and T-helper cell 17, in the immune response to S aureus. These cells are essential for coordinating an effective phagocytic response via cytokine production, indirectly leading to destruction of the organism. It is now widely accepted that next-generation S aureus vaccines must also induce effective T-cell-mediated immunity. However, there remains a gap in our knowledge: how will an S aureus vaccine drive these responses in those patients most at risk? Given that patients on hemodialysis are an immunocompromised population, in particular with specific T-cell defects, including defects in T-helper cell subsets, this is likely to affect their ability to respond to an S aureus vaccine. We urgently need a better understanding of T-cell-mediated immunity in this cohort if an efficacious vaccine is ever to be realized for these patients.

Monogenic causes of chronic kidney disease in adults.

Approximately 500 monogenic causes of chronic kidney disease (CKD) have been identified, mainly in pediatric populations. The frequency of monogenic causes among adults with CKD has been less extensively studied. To determine the likelihood of detecting monogenic causes of CKD in adults presenting to nephrology services in Ireland, we conducted whole exome sequencing (WES) in a multi-centre cohort of 114 families including 138 affected individuals with CKD. Affected adults were recruited from 78 families with a positive family history, 16 families with extra-renal features, and 20 families with neither a family history nor extra-renal features. We detected a pathogenic mutation in a known CKD gene in 42 of 114 families (37%). A monogenic cause was identified in 36% of affected families with a positive family history of CKD, 69% of those with extra-renal features, and only 15% of those without a family history or extra-renal features. There was no difference in the rate of genetic diagnosis in individuals with childhood versus adult onset CKD. Among the 42 families in whom a monogenic cause was identified, WES confirmed the clinical diagnosis in 17 (40%), corrected the clinical diagnosis in 9 (22%), and established a diagnosis for the first time in 16 families referred with CKD of unknown etiology (38%). In this multi-centre study of adults with CKD, a molecular genetic diagnosis was established in over one-third of families. In the evolving era of precision medicine, WES may be an important tool to identify the cause of CKD in adults.

Progressive improvement in short-, medium- and long-term graft survival in kidney transplantation patients in Ireland - a retrospective study.

It is often quoted that while short-term graft survival in kidney transplantation has improved in recent years, it has not translated into a commensurate improvement in long-term graft survival. We considered whether this was true of the entire experience of the national kidney transplant program in Ireland. A retrospective analysis of the National Kidney Transplant Service (NKTS) database was undertaken to investigate patient and graft survival for all adult first deceased donor kidney transplant recipients in Ireland, 1971-2015. Three thousand two hundred and sixty recipients were included in this study. Kaplan-Meier methods were used to estimate survival at each time period post transplant for the various eras of transplantation. Uncensored graft survival has improved over the course of the program in Ireland at various time points despite risk factors for graft failure progressively increasing over successive eras. For example the graft survival at 15 years post transplant has increased from 10% in 1971-1975 to 45% by 1996-2000. Ireland has experienced a progressive improvement in long-term graft survival following kidney transplantation. Whether these trends are attributable to biological or nonbiological factors is unclear but likely involves a combination of both.

The Irish living kidney donor program - why potential donors do not proceed to live kidney donation?

BACKGROUND: Living donation is not only a method to increase access to kidney transplantation but can also offer superior outcomes. We report the experience of the living donor (LD) program in the Republic of Ireland and explore reasons why potential donors do not proceed to live donation. METHODS: Retrospective cohort study of all potential donors from January 2000 to March 2014 who presented wishing to undergo donor work-up and their subsequent outcomes. RESULTS: A total of 956 donors for 496 recipients contacted the live kidney donation program of which 883 potential donors proceeded to the initial stage of assessment. The donor dropout rate at this stage was 64.2% (614/956 potential donors did not proceed to further evaluation). Thereafter, 269 (28.1%) donors underwent further assessment by the multidisciplinary team. In total, 93 (9.7%) donors were declined following this assessment with 176 (18.4%) donors ultimately proceeding to live kidney donation. The major reason for declining a donor was a medical contraindication (n = 63, 67.7%). In term of recipients, 54.2% (n = 269/496) had a potential donor proceed for further assessment of which 65.4% (n = 176/269) ultimately proceeding to live donation. CONCLUSION: Further evaluation of the declined donor group is warranted to allow for expansion of the LD program.

Factors affecting eGFR 5-year post-deceased donor renal transplant: analysis and predictive model.

AIM: Long-term survival of renal allografts has improved over the last 20 years. However, less is known about current expectations for long-term allograft function as determined by estimated glomerular filtration rate (eGFR). The aim of this study was to investigate factors which affect graft function at 5 years' post-renal transplantation. The statistically significant factors were then used to construct a predictive model for expected eGFR at five years' post-transplant. METHODS: We retrospectively reviewed all adult patients who received a renal transplant in the Republic of Ireland between 1990 and 2004. Data collected included era of transplantation (1990-1994, 1995-1999, 2000-2004), donor and recipient age and gender, number of human leucocyte antigen mismatches, cold ischemia time (CIT), number of prior renal transplants, immunosuppressive regimen used and acute rejection episodes. Estimated GFR was calculated at 5 years after transplantation from patient data using the Modified Diet in Renal Disease (MDRD) equation. Consecutive sampling was used to divide the study population into two equal unbiased groups of 489 patients. The first group (derivation cohort) was used to construct a predictive model for eGFR five years' post-transplantation, the second (validation cohort) to test this model. RESULTS: Nine hundred and seventy eight patients were analyzed. The median age at transplantation was 43 years (range 18-78) and 620 (63.4%) were male. One hundred and seventy five patients (17.9%) had received a prior renal transplant. Improved eGFR at five years' post-transplantation was associated with tacrolimus-based combination immunosuppression, younger donor age, male recipient, absence of cytomegalovirus disease and absence of acute rejection episodes as independently significant factors (p < 0.05). The predictive model developed using these factors showed good correlation between predicted and actual median eGFR at five years. The model explained 20% of eGFR variability. The validation model findings were consistent with the derivation model (21% variability of eGFR explained by model using same covariates on new data). CONCLUSION: The predictive model we have developed shows good correlation between predicted and actual median eGFR at five years' post-transplant. Applications of this model include comparison of current and future therapy options such as new immunosuppressive regimens.

Glomerular disease recurrence in second and subsequent kidney transplants.

INTRODUCTION: Primary glomerular diseases such as primary focal segmental glomerular sclerosis (FSGS), IgA Nephropathy and membrano-proliferative glomerulonephritis (MPGN) may recur in renal transplants, and can potentially lead to graft failure. The rate of recurrence in second and subsequent renal transplants, following failure of the first graft due to recurrence, is unclear. METHODS: A retrospective review of the Irish transplant database from 1982 to 2009 was performed. Patients were included for analysis if their first graft failed due to biopsy-confirmed recurrent glomerular disease (primary FSGS, IgA nephropathy or MPGN) and they underwent subsequent re-transplantation. RESULTS: 3,330 deceased and living renal transplants were performed during the time period in question. 33 patients had a deceased donor renal transplant following recurrence of primary FSGS, IgA nephropathy or MPGN causing first graft failure. Clinically significant disease recurrence was seen in 44% of re-transplants at 10 years. Median second graft survival in this group was 9.1 years. The median graft survival was 10.5 years for all other re-transplants performed in Ireland during the same time period. CONCLUSION: Clinically significant disease recurrence does not necessarily affect re-transplants following loss of the first graft to disease recurrence. Selected patients who experience first graft failure due to recurrent glomerular disease should not be precluded from receiving a second transplant.

Clinical and pathologic characteristics of hereditary apolipoprotein A-I amyloidosis in Ireland.

AIM: Apolipoprotein A-I amyloidosis is a rare, autosomal dominant disorder characterized by progressive accumulation of amyloid fibrils in tissues, leading to renal and hepatic disease. We describe the clinical manifestations and pathologic features of kidney disease in three Irish families. METHODS: This observational study examines all known cases of chronic kidney disease due to hereditary apolipoprotein A-I amyloidosis in Ireland. Patients were identified by physician interview. In all of the affected individuals the disease was caused by the Gly26Arg heterozygous mutation. Immunohistochemistry confirmed that amyloid deposits were composed of apolipoprotein A-I fibrils. Family trees and clinical data were obtained via analysis of patient medical records. RESULTS: The vast majority of affected cases had demonstrable kidney disease, with variable liver disease. Renal disease most commonly manifested as slowly progressive renal impairment with mild proteinuria. In one kindred, a severe, debilitating peripheral neuropathy was common among affected family members. Histology demonstrated tubulointerstitial fibrosis with amyloid deposition in the medulla. There was very high penetrance within affected families. Of five patients who were transplanted, one transplant was lost after 5 years due to recurrent disease. One patient died from sepsis shortly after transplant. CONCLUSION: Hereditary apolipoprotein A-I amyloidosis is characterized by slowly progressive renal disease. Amyloid is deposited in the renal medulla highlighting the need to examine the medulla on renal biopsy. Overall, kidney transplantation conferred a survival advantage.

Concordance of outcomes of pairs of kidneys transplanted into different recipients.

Kidney transplant outcomes are influenced by donor characteristics, including age and gender. Additional donor factors, both genetic and environmental, also influence graft outcome. We aim to assess the strength of donor factors in determining kidney transplant outcomes by comparing paired kidneys from a single donor transplanted into different recipients. We conducted a retrospective cohort study of outcomes of pairs of deceased donor kidneys transplanted in our centre between 1992 and 2008. We examined the relationship within pairs for eGFR at 1 year and at 5 years post-transplant using Spearman's Correlation and the concordance of pairs of transplant kidneys with respect to the occurrence of acute rejection and delayed graft function (DGF). A total of 652 recipient pairs were analysed. Spearman's correlation for eGFR was 0.36 at 1 year and 0.36 at 5 years post-transplant. The incidence of DGF was 11%. The odds ratio of DGF occurring if the contralateral kidney had DGF was 5.99 (95% CI, 3.19-11.25). There is a significant degree of relationship within pairs of kidneys transplanted from the same donor for serum creatinine at 1 year and 5 years post-transplant and also for the occurrence of delayed graft function.

Effect of perioperative blood transfusions on long term graft outcomes in renal transplant patients.

BACKGROUND: It is established that blood transfusions will promote sensitization to human leucocyte antigen (HLA) antigens, increase time spent waiting for transplantation and may lead to higher rates of rejection. Less is known about how perioperative blood transfusion influence patient and graft outcome. This study aims to establish if there is an association between perioperative blood transfusion and graft or patient survival. MATERIALS AND METHODS: This was a single center, national, retrospective cohort study. Data was collected on patients who received kidney transplants over a 14-year period (n = 2,013). The primary outcomes were graft survival and mortality in patients who received blood transfusions in the perioperative period compared to those who did not. RESULTS: Patients who received blood transfusions had lower hemoglobin levels, were more likely to be male, and had higher rates of delayed graft function compared to those who did not receive a transfusion. The one year graft survival of those transfused was 83% compared to 94% in those not transfused (p = < 0.0001). Adjustment for confounding showed that the receipt of a blood transfusion remained associated with increased graft loss. Hemoglobin levels prior to transfusion did not have an influence on graft outcome. CONCLUSION: Perioperative blood transfusion is associated with reduced long-term graft survival.

Management and Outcomes of ANCA-Associated Vasculitis at a Tertiary Healthcare Facility.

RESULTS: Thirty-six patients were included in the final study. Cyclophosphamide was used in 24 patients (66.7%) and, comparatively, rituximab in 7 patients (19.4%) for induction. Seven patients (19.4%) had a documented relapse, and six patients (85.7%) had rituximab as induction therapy for relapse. The majority of patients were on azathioprine (61.1%, 57.1% relapse population) as maintenance therapy. Progression to ESRD occurred in 11 (30.6%), death in 4 (11.1%), established CKD in 15 (41.7%), and preservation of renal function in 6 (16.7%) patients by the end of the follow-up period. CONCLUSIONS: While cyclophosphamide remains the choice of induction immunosuppression therapy, we favour rituximab as an induction agent in the relapse of AAV. Despite aggressive immunosuppression therapy, the incidence of ESRD and death remains high in these patients.

Progressive survival improvement of incident dialysis patients in a tertiary center, Ireland.

BACKGROUND: The survival of incident dialysis patients' end-stage kidney disease in some European and American has been reported to improve in modern era compared to earlier periods. However, in Ireland, this has not been well documented. AIM: To investigate the survival outcomes of incident end-stage kidney failure dialysis patients in a tertiary center over a 24-year period, 1993-2017. METHODS: A retrospective analysis was carried out utilizing the Beaumont Hospital Renal Database. Consecutive adults with incident dialysis were analyzed. Kaplan-Meier methods and the estimated mean survival times were used to evaluate survival at successive 4-year periods of time. RESULTS: In total, 2106 patients were included, of whom 830 underwent subsequent renal transplantation during follow-up. During the study period, from 1993 up to 2017, the mean patients' age increased from 56.3 ± 17.4 in 1993-1996 to 60.6 ± 18.3 in 2014-2017. There was an overall decrement in mortality over successive time intervals which were mirrored by the improvements in median survival after commencement of dialysis treatment from 6.14 years during 1993-1996 to 8.01 years during 2009-2012. Patients' survival has steadily improved, with the 5-year survival has risen over time, by almost 15%. This positive signal persisted and became more pronounced after adjusting Kaplan-Meier curve to age, where the 5-year survival estimates were exceeding 80% in 2014-2017. CONCLUSION: Survival rates among incident dialysis patients have improved progressively between 1993 and 2017 in Beaumont Hospital in Dublin, Ireland. The factors which led to this improvement are not entirely clear, but likely to be multifactorial.

Risk factors and long-term consequences of new-onset diabetes after renal transplantation.

BACKGROUND: New-onset diabetes after transplant (NODAT) confers risk of diabetes-related complications as well as a threat to graft function and overall patient survival. The reported incidence of NODAT varies from 14 to 37% in renal transplant recipients worldwide; however, NODAT is yet to be studied in the Irish renal transplant population. AIMS: Primary aims of this project were to estimate the incidence, to determine associated risk factors and to assess the long-term consequences of NODAT on graft survival and patient survival in the Irish renal transplant population. METHODS: Retrospective data collection of 415 renal transplant recipients over a 12-year period was performed to record presence of NODAT, patient characteristics and perioperative management. Preoperative screening was reviewed in a subgroup of patients to determine concordance with the International Consensus Guidelines. Statistical analysis was performed using Kaplan-Meier survival functions estimating NODAT detection over time, graft and patient survival. Risk factor association was determined using Cox proportional-hazards models. RESULTS: NODAT incidence was 10.2% in the first 5 years of post-transplant. Risk factors for developing NODAT were recipient age and body weight. Risk of NODAT was highest in the first year of post-transplant and conferred decreased patient survival; however, it did not significantly affect graft survival. Only seven patients of a subgroup of 21 patients who developed NODAT had preoperative testing for diabetes. CONCLUSIONS: NODAT incidence in the Irish renal transplant population is slightly below international figures. This project has highlighted current deficits in the national transplant guidelines for the detection of NODAT and NODAT-related risk factors.

Early results of a controlled non-heart-beating kidney donor programme.

BACKGROUND: We present our experience of a controlled non-heart beating donation (CNHBD) programme in a University Hospital. METHODS: Data from all referrals for CNHBD between January 2005 and January 2008 were collected prospectively. Donor and recipient data were analysed and compared to other cadaveric and HBD transplants performed during the same period. RESULTS: During the period, 79 donors were referred resulting in 35 proceeding to retrieval and 61 kidneys being successfully transplanted. The median time from withdrawal of therapy to asystole was 15 min (IQR 10.0-23.0). The median primary warm ischaemic time was 20 min (IQR 16.0-27.0). The mean cold ischaemia time was 16.6 +/- 4.21 h for CNHBD (16.6 +/- 5.91 for HBD) kidneys. Compared to HBD kidneys, CNHBD kidneys had more HLA mismatches and significantly more delayed graft function (44% versus 14%), and the mean time to halving of serum creatinine was significantly greater (12.8 versus 5 days). However, 1-year patient and graft survival (88% and 93%) were excellent and mean creatinine at 12 months for CNHB kidneys was not significantly different from HBD kidneys (141 mumol/l versus 131 mumol/l). CONCLUSIONS: Structured implementation resulted in a successful CNHBD programme providing 61 successful renal transplants from 35 donors in 3 years-contributing to approximately 50% of the total number of cadaveric renal transplants during the period. At 12 months, CNHBD kidney graft function was equivalent to HBD organs.

Assessing the discrimination of the Kidney Donor Risk Index/Kidney Donor Profile Index scores for allograft failure and estimated glomerular filtration rate in Ireland's National Kidney Transplant Programme.

BACKGROUND: The Kidney Donor Risk Index (KDRI)/Kidney Donor Profile Index (KDPI) is relied upon for donor organ allocation in the USA, based on its association with graft failure in time-to-event models. However, the KDRI/KDPI has not been extensively evaluated in terms of predictive metrics for graft failure and allograft estimated glomerular filtration rate (eGFR) outside of the USA. METHODS: We performed a retrospective analysis of outcomes in the Irish National Kidney Transplant Service Registry for the years 2006-13. Associations of the KDRI/KDPI score with eGFR at various time points over the follow-up and ultimate graft failure were modelled. RESULTS: A total of 772 patients had complete data regarding KDRI/KDPI calculation and 148 of these allografts failed over the follow-up. The median and 25-75th centile for KDRI/KDPI was 51 (26-75). On repeated-measures analysis with linear mixed effects models, the KDRI/KDPI (fixed effect covariate) associated with eGFR over 5 years: eGFR = -0.25 (standard error 0.02; P < 0.001). The variability in eGFR mathematically accounted for by the KDRI/KDPI score was only 21%. The KDRI/KDPI score did not add significantly to graft failure prediction above donor age alone (categorized as > and <50 years of age) when assessed by the categorical net reclassification index. CONCLUSIONS: In this cohort, while the KDRI/KDPI was predictive of eGFR over the follow-up, it did not provide additive discrimination above donor age alone in terms of graft failure prediction. Therefore it is unlikely to help inform decisions regarding kidney organ allocation in Ireland.

TNP-470, an angiogenesis inhibitor, attenuates the development of allograft vasculopathy.

Fischer 344 rat recipients of Lewis allografts were treated with TNP-470, a synthetic fumagillin derivative and a well-established angiogenesis inhibitor. TNP-470 alone resulted in some prolongation of graft survival as compared with untreated recipients, but all grafts ultimately failed. In contrast, treatment with cyclosporine (CsA) from day 0 to 30 resulted in prolonged graft survival and marked cardiac allograft vasculopathy (CAV) by histology (mean score 2.28+/-0.2). There were many neovessels within the intima of CAV lesions. When TNP-470 was administered in combination with CsA from day 0 to 30, the degree of CAV was similar to that with CsA alone (mean score 2.22+/-0.26). However, when TNP-470 was administered from day 30 to 120 after discontinuation of CsA, there was a marked reduction in the degree of CAV (mean score 1.08+/-0.11). Therefore, TNP-470 interrupts the progression of CAV when given late but does not prevent its development when given immediately posttransplantation.

Statin specific toxicity in organ transplant recipients: case report and review of the literature.

Statins are widely prescribed to organ transplant recipients with hyperlipidemia. We report the case of a cardiac transplant recipient who developed severe rhabdomyolysis and acute renal failure after being switched from pravastatin to simvastatin. The patient's other medications included cyclosporin A and diltiazem. Unlike pravastatin, the metabolism and tissue concentrations of simvastatin--and of other statins - can be greatly affected by these drugs. The propensity of the individual statins to interact with drugs commonly prescribed to transplant recipients is reviewed.

DNA microarrays: applicability to renal physiology and disease.

The utilization of DNA microarray is increasing in all areas of medical research as evidenced by the exponential increase in the number of publications on MedLine. Improvements in DNA microarray technology and the bioinformatic techniques for data analysis continue to take place and result in improved reliability, reproducibility, and volume of data. Replicate analysis remains important in order to allow statistical examination of significance. Expression of key genes should also be confirmed by alternative techniques. Single microarray experiments yield such vast amounts of data that shortage of manpower is the limiting factor to progression of full scientific discovery. Sharing of microarray data on the internet and its distribution to a broader scientific community will help overcome this manpower shortage. Currently, DNA microarray technology serves as a research tool. Ultimately, microarray technology may be used widely in the clinical setting as fingerprinting of cells, tissue, and disease states, though more targeted strategies using a limited repertoire of genes may be most valuable.