Investigating Biomarkers for USH2A Retinopathy Using Multimodal Retinal Imaging

Pathogenic mutations in USH2A are a leading cause of visual loss secondary to non-syndromic or Usher syndrome-associated retinitis pigmentosa (RP). With an increasing number of RP-targeted clinical trials in progress, we sought to evaluate the photoreceptor topography underlying patterns of loss observed on clinical retinal imaging to guide surrogate endpoint selection in USH2A retinopathy. In this prospective cross-sectional study, twenty-five patients with molecularly confirmed USH2A-RP underwent fundus autofluorescence (FAF), spectral-domain optical coherence tomography (SD-OCT) and adaptive optics scanning laser ophthalmoscopy (AOSLO) retinal imaging. Analysis comprised measurement of FAF horizontal inner (IR) and outer (OR) hyperautofluorescent ring diameter; SD-OCT ellipsoid zone (EZ) and external limiting membrane (ELM) width, normalised EZ reflectance; AOSLO foveal cone density and intact macular photoreceptor mosaic (IMPM) diameter. Thirty-two eyes from 16 patients (mean age ± SD, 36.0 ± 14.2 years) with USH2A-associated Usher syndrome type 2 (n = 14) or non-syndromic RP (n = 2) met the inclusion criteria. Spatial alignment was observed between IR-EZ and OR-ELM diameters/widths (p < 0.001). The IMPM border occurred just lateral to EZ loss (p < 0.001), although sparser intact photoreceptor inner segments were detected until ELM disruption. EZ width and IR diameter displayed a biphasic relationship with cone density whereby slow cone loss occurred until retinal degeneration reached ~1350 μm from the fovea, beyond which greater reduction in cone density followed. Normalised EZ reflectance and cone density were significantly associated (p < 0.001). As the strongest correlate of cone density (p < 0.001) and best-corrected visual acuity (p < 0.001), EZ width is the most sensitive biomarker of structural and functional decline in USH2A retinopathy, rendering it a promising trial endpoint.

Cellular imaging of inherited retinal diseases using adaptive optics

Adaptive optics (AO) is an insightful tool that has been increasingly applied to existing imaging systems for viewing the retina at a cellular level. By correcting for individual optical aberrations, AO offers an improvement in transverse resolution from 10-15 μm to ~2 μm, enabling assessment of individual retinal cell types. One of the settings in which its utility has been recognised is that of the inherited retinal diseases (IRDs), the genetic and clinical heterogeneity of which warrants better cellular characterisation. In this review, we provide a summary of the basic principles of AO, its integration into multiple retinal imaging modalities and its clinical applications, focusing primarily on IRDs. Furthermore, we present a comprehensive summary of AO-based cellular findings in IRDs according to their associated disease-causing genes.

Characterisation of microvascular abnormalities using OCT angiography in patients with biallelic variants in USH2A and MYO7A

AIMS

Using optical coherence tomography angiography (OCTA) to characterise microvascular changes in the retinal plexuses and choriocapillaris (CC) of patients with MYO7A and USH2A mutations and correlate with genotype, retinal structure and function.

METHODS

Twenty-seven patients with molecularly confirmed USH2A (n=21) and MYO7A (n=6) mutations underwent macular 6×6 mm OCTA using the AngioVue. Heidelberg spectral-domain OCT scans and MAIA microperimetry were also performed, the preserved ellipsoid zone (EZ) band width and mean macular sensitivity (MS) were recorded. OCTA of the inner retina, superficial capillary plexus (SCP), deep capillary plexus (DCP) and CC were analysed. Vessel density (VD) was calculated from the en face OCT angiograms of retinal circulation.

RESULTS

Forty-eight eyes with either USH2A (n=37, mean age: 34.4±12.2 years) or MYO7A (n=11, mean age: 37.1±12.4 years), and 35 eyes from 18 age-matched healthy participants were included. VD was significantly decreased in the retinal circulation of patients with USH2A and MYO7A mutations compared with controls (p<0.001). Changes were observed in both the SCP and DCP, but no differences in retinal perfusion were detected between USH2A and MYO7A groups. No vascular defects were detected in CC of the USH2A group, but peripheral defects were detected in older MYO7A patients from the fourth decade of life. VD in the DCP showed strong association with MS and EZ width (Spearman's rho =0.64 and 0.59, respectively, p<0.001).

CONCLUSION

OCTA was able to detect similar retinal microvascular changes in patients with USH2A and MYO7A mutations. The CC was generally affected in MYO7A mutations. OCT angiography may further enhance our understanding of inherited eye diseases and their phenotype-genotype associations.

Progressive cone and cone-rod dystrophies: clinical features, molecular genetics and prospects for therapy

Progressive cone and cone-rod dystrophies are a clinically and genetically heterogeneous group of inherited retinal diseases characterised by cone photoreceptor degeneration, which may be followed by subsequent rod photoreceptor loss. These disorders typically present with progressive loss of central vision, colour vision disturbance and photophobia. Considerable progress has been made in elucidating the molecular genetics and genotype-phenotype correlations associated with these dystrophies, with mutations in at least 30 genes implicated in this group of disorders. We discuss the genetics, and clinical, psychophysical, electrophysiological and retinal imaging characteristics of cone and cone-rod dystrophies, focusing particularly on four of the most common disease-associated genes: GUCA1A, PRPH2, ABCA4 and RPGR Additionally, we briefly review the current management of these disorders and the prospects for novel therapies.

Reciprocity to Increase Participation of Compatible Living Donor and Recipient Pairs in Kidney Paired Donation

Inclusion of compatible living donor and recipient pairs (CPs) in kidney paired donation (KPD) programs could increase living donor transplantation. We introduce the concept of a reciprocity-based strategy in which the recipient of a CP who participates in KPD receives priority for a repeat deceased donor transplant in the event their primary living donor KPD transplant fails, and then we review the practical and ethical considerations of this strategy. The strategy limits prioritization to CPs already committed to living donation, minimizing the risk of unduly influencing donor behavior. The provision of a tangible benefit independent of the CP's actual KPD match avoids many of the practical and ethical challenges with strategies that rely on finding the CP recipient a better-matched kidney that might provide the CP recipient a future benefit to increase KPD participation. Specifically, the strategy avoids the potential to misrepresent the degree of future benefit of a better-matched kidney to the CP recipient and minimizes delays in transplantation related to finding a better-matched kidney. Preliminary estimates suggest the strategy has significant potential to increase the number of living donor transplants. Further evaluation of the acceptance of this strategy by CPs and by waitlisted patients is warranted.

Providing Coverage for the Unique Lifelong Health Care Needs of Living Kidney Donors Within the Framework of Financial Neutrality

Organ donation should neither enrich donors nor impose financial burdens on them. We described the scope of health care required for all living kidney donors, reflecting contemporary understanding of long-term donor health outcomes; proposed an approach to identify donor health conditions that should be covered within the framework of financial neutrality; and proposed strategies to pay for this care. Despite the Affordable Care Act in the United States, donors continue to have inadequate coverage for important health conditions that are donation related or that may compromise postdonation kidney function. Amendment of Medicare regulations is needed to clarify that surveillance and treatment of conditions that may compromise postdonation kidney function following donor nephrectomy will be covered without expense to the donor. In other countries lacking health insurance for all residents, sufficient data exist to allow the creation of a compensation fund or donor insurance policies to ensure appropriate care. Providing coverage for donation-related sequelae as well as care to preserve postdonation kidney function ensures protection against the financial burdens of health care encountered by donors throughout their lives. Providing coverage for this care should thus be cost-effective, even without considering the health care cost savings that occur for living donor transplant recipients.

Integrating APOL1 Gene Variants Into Renal Transplantation: Considerations Arising From the American Society of Transplantation Expert Conference

Thirteen percent of individuals of African ancestry express two variant copies of the gene encoding apolipoprotein 1 (APOL1) that has been associated with an increased risk of end-stage renal disease (ESRD) in the general population. Limited studies suggest that the survival of transplanted kidneys from donors expressing two APOL1 risk alleles is inferior to that of kidneys from donors with zero or one risk allele. In living kidney donation, two case reports describe donors expressing two APOL1 risk alleles who developed ESRD. Given the potential impact of APOL1 variants on the utility and safety of kidney transplantation and living kidney donation, the American Society of Transplantation convened a meeting with the goals of summarizing the current state of knowledge with respect to transplantation and APOL1, identifying knowledge gaps and studies to address these gaps, and considering approaches to integrating APOL1 into clinical practice. The authors recognize that current data are not sufficient to support traditional evidence-based guidelines but also recognize that it may require several years to generate the necessary data. Thus, approaches as to how APOL1 might currently be integrated into the clinical decision-making process were considered. This report summarizes the group's deliberations.

Towards Improving the Transfer of Care of Kidney Transplant Recipients

Kidney transplant recipients require specialized medical care and may be at risk for adverse health outcomes when their care is transferred. This document provides opinion-based recommendations to facilitate safe and efficient transfers of care for kidney transplant recipients including minimizing the risk of rejection, avoidance of medication errors, ensuring patient access to immunosuppressant medications, avoidance of lapses in health insurance coverage, and communication of risks of donor disease transmission. The document summarizes information to be included in a medical transfer document and includes suggestions to help the patient establish an optimal therapeutic relationship with their new transplant care team. The document is intended as a starting point towards standardization of transfers of care involving kidney transplant recipients.

Timing of Pregnancy After Kidney Transplantation and Risk of Allograft Failure

The optimal timing of pregnancy after kidney transplantation remains uncertain. We determined the risk of allograft failure among women who became pregnant within the first 3 posttransplant years. Among 21 814 women aged 15-45 years who received a first kidney-only transplant between 1990 and 2010 captured in the United States Renal Data System, n = 729 pregnancies were identified using Medicare claims. The probability of allograft failure from any cause including death (ACGL) at 1, 3, and 5 years after pregnancy was 9.6%, 25.9%, and 36.6%. In multivariate analyses, pregnancy in the first posttransplant year was associated with an increased risk of ACGL (hazard ratio [HR]: 1.18; 95% confidence interval [CI] 1.00, 1.40) and death censored graft loss (DCGL) (HR:1.25; 95% CI 1.04, 1.50), while pregnancy in the second posttransplant year was associated with an increased risk of DCGL (HR: 1.26; 95% CI 1.06, 1.50). Pregnancy in the third posttransplant year was not associated with an increased risk of ACGL or DCGL. These findings demonstrate a higher incidence of allograft failure after pregnancy than previously reported and that the increased risk of allograft failure extends to pregnancies in the second posttransplant year.

Engaging Living Kidney Donors in a New Paradigm of Postdonation Care

Recent studies have highlighted the need for better understanding of the long-term health outcomes of living donors. Barriers to establishment of a dedicated long-term donor follow-up data system in the United States include infrastructure costs and donor retention. We propose providing all previous and future living donors with a lifelong health insurance benefit for the primary purpose of facilitating acquisition of health information after donation as an alternative to establishment of a dedicated donor follow-up data system. Donors would consent to allow collection and analysis of their medical data, and continuation of insurance coverage would require completion of regular health assessments. The extension of health insurance would be analogous to the established practice of paying people for participation in a research study and would provide a mechanism to engage donors in a new paradigm of postdonation care in which donors are actively involved in their own health maintenance. Rather than acting as an inducement for donation, providing donors with the ability to easily contribute information about their health status represents a practical strategy to acquire the long-term medical information necessary to better inform future generations of living kidney donors.

Prevalence of Multidrug-resistant, Extensively Drug-resistant, and Pandrug-resistant Pseudomonas aeruginosa from a Tertiary Level Intensive Care Unit

Background:

Infection by Pseudomonas aeruginosa is common in the Intensive Care Unit (ICU), leading to increased morbidity and mortality. The organism is classified into various phenotypes based on the drug resistance pattern, namely, drug-resistant (DR), multi-DR (MDR), extensively DR (XDR), and pan-DR (PDR). We aim to study the incidence of P. aeruginosa phenotypes in a tertiary level ICU.

Materials and Methods:

We conducted this prospective, observational study for 2 years (January 2014-December 2015) and collected appropriate clinical samples (blood, urine, wound discharge, etc.,) from all the patients admitted to ICU. We excluded patients with known septicemia and P. aeruginosa infection. Group 1 comprised a total 1915 patient samples and Group 2 comprised 100 active surveillance samples, collected from the medical staff and the hospital environment. The data were analyzed using appropriate statistical methods, and a P < 0.05 was considered statistically significant.

Results:

We isolated 597 pathogenic bacteria out of 1915 specimens, giving a culture positivity rate of 31.2%. Klebsiella (43%), Acinetobacter (22%), and P. aeruginosa (15%) were the top three isolated bacteria. None of the surveillance samples grew P. aeruginosa. Antibiotic resistance studies revealed that 47.7% of P. aeruginosa isolates were DR, 50% were MDR, and 2.3% were XDR phenotype. None of the strains showed PDR phenotype.

Conclusion:

Our data revealed a high prevalence of DR phenotypes of P. aeruginosa in the ICU. Judicious use of antibiotics and strict infection control measures are essential to reduce the prevalence of drug resistance.

Advances in the understanding of complement mediated glomerular disease: implications for recurrence in the transplant setting

Recent advances in the understanding of the role of complement in glomerular disease allow for more accurate assessment of the risk of disease recurrence after transplantation, and inform the development of targeted treatment strategies to overcome specific defects in the alternate pathway of the complement system. These advances along with remaining knowledge deficits are reviewed with specific relevance to membranoproliferative glomerulonephritis (MPGN) and C3 glomerulopathy, a heterogenous group of diseases with a high rate of recurrence leading to allograft failure. Recommendations to establish an accurate diagnosis and inform therapeutic decision making in transplant candidates with a histologic diagnosis of MPGN are provided.

Economic consequences incurred by living kidney donors: a Canadian multi-center prospective study

Some living kidney donors incur economic consequences as a result of donation; however, these costs are poorly quantified. We developed a framework to comprehensively assess economic consequences from the donor perspective including out-of-pocket cost, lost wages and home productivity loss. We prospectively enrolled 100 living kidney donors from seven Canadian centers between 2004 and 2008 and collected and valued economic consequences ($CAD 2008) at 3 months and 1 year after donation. Almost all (96%) donors experienced economic consequences, with 94% reporting travel costs and 47% reporting lost pay. The average and median costs of lost pay were $2144 (SD 4167) and $0 (25th-75th percentile 0, 2794), respectively. For other expenses (travel, accommodation, medication and medical), mean and median costs were $1780 (SD 2504) and $821 (25th-75th percentile 242, 2271), respectively. From the donor perspective, mean cost was $3268 (SD 4704); one-third of donors incurred cost >$3000, and 15% >$8000. The majority of donors (83%) reported inability to perform usual household activities for an average duration of 33 days; 8% reported out-of-pocket costs for assistance with these activities. The economic impact of living kidney donation for some individuals is large. We advocate for programs to reimburse living donors for their legitimate costs.

Hypercalcemia in renal transplant patients: prevalence and management in Canadian transplant practice

Hypercalcemia, occurring in up to 25% of patients within 12 months following renal transplantation, and persistent hyperparathyroidism were evaluated following renal transplantation, by retrospective chart review of 1000 adult patients transplanted between January 1, 2003 and January 31, 2008 with at least six months follow-up. Serum calcium, parathyroid hormone, and phosphate levels were recorded at 12, 24, 36, and 48 months. Average follow-up was 766 (535) d (mean (SD); median 668 d). Majority were first transplants (85%); deceased donor 57%. Point prevalence of hypercalcemia (serum Ca(2+) > 2.6 mM) was 16.6% at month 12, 13.6% at month 24, 9.5% at month 36, and 10.1% at month 48. Point prevalence of serum parathyroid hormone (PTH) > 10 pM was 47.6% at month 12, 51.1% at month 24, 43.4% at month 36, and 39.3% at month 48. Estimated glomerular filtration rate (GFR) was maintained throughout and was not different between patients with or without hypercalcemia or elevated PTH. Cinacalcet was prescribed in 12% of patients with hypercalcemia and persistent hyperparathyroidism; parathyroidectomy was performed in 112/1000 patients, 15 post-transplant. Persistent hyperparathyroidism, often accompanied by hypercalcemia, is common following successful renal transplantation, but the lack of clear management suggests the need for further study and development of evidence-based guidelines.

The survival benefit of kidney transplantation in obese patients

Obese patients have a decreased risk of death on dialysis but an increased risk of death after transplantation, and may derive a lower survival benefit from transplantation. Using data from the United States between 1995 and 2007 and multivariate non-proportional hazards analyses we determined the relative risk of death in transplant recipients grouped by body mass index (BMI) compared to wait-listed candidates with the same BMI (n = 208 498). One year after transplantation the survival benefit of transplantation varied by BMI: Standard criteria donor transplantation was associated with a 48% reduction in the risk of death in patients with BMI ≥ 40 kg/m(2) but a ≥ 66% reduction in patients with BMI < 40 kg/m2. Living donor transplantation was associated with ≥ 66% reduction in the risk of death in all BMI groups. In sub-group analyses, transplantation from any donor source was associated with a survival benefit in obese patients ≥ 50 years, and diabetic patients, but a survival benefit was not demonstrated in Black patients with BMI ≥ 40 kg/m(2). Although most obese patients selected for transplantation derive a survival benefit, the benefit is lower when BMI is ≥ 40 kg/m(2), and uncertain in Black patients with BMI ≥ 40 kg/m(2).

Lower incidence of inappropriate shock therapy in patients with combined cardiac resynchronisation therapy defibrillators (CRT-D) compared with patients with non-CRT defibrillators (ICDs)

INTRODUCTION

A significant number of patients experience inappropriate shock therapy (IST) from implantable cardioverter-defibrillators (ICD). An increasing number of patients with advanced heart failure receive combined ICD and cardiac resynchronisation therapy devices (CRT-D). The incidence of IST in this group is less well described. We aimed to assess the incidence and predictors of IST in CRT-D patients.

METHODS

A retrospective cohort study of prospectively collected data on patients who received an ICD and CRT-D between October 2007 and January 2009 at our institution were studied. The primary outcome measures were the IST event rate and all-cause mortality.

RESULTS

A total of 185 patients with ICD/CRT-D (100/85) were included in the analysis. Eighteen patients experienced 35 episodes of IST during the follow-up (21 ± 13 months). There was a significantly lower IST cumulative event rate in the CRT-D vs. ICD group, 5% (CI: 1-13%) vs. 19% (95% CI: 11-30%) by 24 months, (p = 0.017). The majority of the IST was caused by atrial arrhythmias with atrial fibrillation accounting for 28 episodes of IST in nine patients. Multivariate analysis using Cox hazard model including baseline characteristics and coexisting appropriate shock therapy showed that a history of atrial fibrillation/flutter was the strongest independent predictor of IST with a hazard ratio of 3.53 (p = 0.019).

CONCLUSION

Patients with CRT-D had a significantly lower incidence of IST compared with patients receiving an ICD. Given that atrial arrhythmia remained the commonest trigger for IST, our finding lends support to the hypothesis that CRT may reduce atrial fibrillation burden in patients receiving CRT-D.

Quantification of the early risk of death in elderly kidney transplant recipients

To inform decision making regarding transplantation in patients ≥ 65 years, we quantified the early posttransplant risk of death by determining the time to equal risk and equal survival between transplant recipients and wait-listed dialysis patients in the United States between 1995 and 2007 (total n = 25 468). Survival was determined using separate multivariate nonproportional hazards analyses in low-, intermediate- and high-risk cardiovascular risk patients. Compared to wait-listed patients with similar cardiovascular risk, standard criteria (SCD) and expanded criteria (ECD) recipients had a higher risk of death in the perioperative and early-posttransplant period. In contrast, low and intermediate risk living donor (LD) recipients had an immediate survival advantage compared to similar risk wait-listed patients. In all risk groups, transplantation was associated with a long-term survival advantage compared to dialysis, but there were marked differences in time to equal risk of death, and time to equal survival by donor type. For example, survival in high-risk recipients of an LD, SCD and ECD transplant became equal to that in similar risk wait-listed patients 130, 368 and 521 days after transplantation. Early posttransplant mortality risk is eliminated in low- and intermediate-risk patients, and markedly reduced in high-risk patients with LD transplantation.

Yield and fibre quality associated with cotton leaf curl disease of Bt-cotton in Punjab

Cotton leaf curl disease (CLCuD), caused by Gemini virus and transmitted through whitefly (Bemisia tabaci) is a serious problem in Northern India, affecting the productivity to a great extent. Depending upon the severity of infection in susceptible varieties, the disease can cause upto 90.0 % yield losses besides this, it also causes deterioration in fibre quality. The objective of the present study was to determine the effect of cotton leaf curl disease on seed cotton yield and fibre characters of two popular Bt-cotton hybrids in Punjab. The disease caused 52.7% reduction in number of bolls and 54.2 % in boll weight in Bt cotton hybrid RCH 134. Similarly, it reduced the fibre length from 29.1 to 26.2 mm (9.9%); fibre uniformity from 68.9 to 68.1% (1.1%); fibre strength from 29.1 to 26.9 g per texture (7.5%) and miconaire value from 5.2 to 5.0 g inch(-1) (3.8%). Similar results were reported in Bt cotton hybrid MRC 6304, where the disease reduced the boll number and boll weight by 46.1 and 43.4%, respectively. However, to the fibre quality was not much affected by varying level of disease severity. The studies clearly reflect the adverse impact of CLCuD on yield and fibre quality especially 2.5% span length. Thus suggesting the management of disease using integrated disease management strategies to avoid quantitative and qualitative losses.

Income of living kidney donors and the income difference between living kidney donors and their recipients in the United States

Disincentives for living kidney donation are common but are poorly understood. We studied 54 483 living donor kidney transplants in the United States between 2000 and 2009, limiting to those with valid zip code data to allow determination of median household income by linkage to the 2000 U.S. Census. We then determined the income and income difference of donors and recipients. The median household income in donors and recipients was $46 334 ±$17 350 and $46 439 ±$17 743, respectively. Donation-related expenses consume ≥ 1 month's income in 76% of donors. The mean ± standard deviation income difference between recipients and donors in transplants involving a wealthier recipient was $22 760 ± 14 792 and in 90% of transplants the difference was <$40 000 dollars. The findings suggest that the capacity for donors to absorb the financial consequences of donation, or of recipients to reimburse allowable expenses, is limited. There were few transplants with a large difference in recipient and donor income, suggesting that the scope and value of any payment between donors and recipients is likely to be small. We conclude that most donors and recipients have similar modest incomes, suggesting that the costs of donation are a significant burden in the majority of living donor transplants.

Modeling oxygen transport in human placental terminal villi

Oxygen transport from maternal blood to fetal blood is a primary function of the placenta. Quantifying the effectiveness of this exchange remains key in identifying healthy placentas because of the great variability in capillary number, caliber and position within the villus-even in placentas deemed clinically "normal". By considering villous membrane to capillary membrane transport, stationary oxygen diffusion can be numerically solved in terminal villi represented by digital photomicrographs. We aim to provide a method to determine whether and if so to what extent diffusional screening may operate in placental villi. Segmented digital photomicrographs of terminal villi from the Pregnancy, Infection and Nutrition study in North Carolina 2002 are used as a geometric basis for solving the stationary diffusion equation. Constant maternal villous oxygen concentration and perfect fetal capillary membrane absorption are assumed. System efficiency is defined as the ratio of oxygen flux into a villus and the sum of the capillary areas contained within. Diffusion screening is quantified by comparing numerical and theoretical maximum oxygen fluxes. A strong link between various measures of villous oxygen transport efficiency and the number of capillaries within a villus is established. The strength of diffusional screening is also related to the number of capillaries within a villus. Our measures of diffusional efficiency are shown to decrease as a function of the number of capillaries per villus. This low efficiency, high capillary number relationship supports our hypothesis that diffusional screening is present in this system. Oxygen transport per capillary is reduced when multiple capillaries compete for diffusing oxygen. A complete picture of oxygen fluxes, capillary and villus areas is obtainable and presents an opportunity for future work.

Aggressive renal angiomyolipoma extending into the renal vein and inferior vena cava - an uncommon entity

Renal angiomyolipoma is recognised as a benign hamartomatous lesion with no obvious malignant potential. However, the tumour may show extrarenal/perinephric extension at times. Rarely, the lesion may extend into the renal vein and inferior vena cava (IVC) indicating aggressive behaviour. We present a case of an angiomyolipoma of the kidney with sonographic, CT and MRI evidence of extension into the renal vein and IVC.

The impact of pancreas transplantation on kidney allograft survival

Whether pancreas after kidney transplantation (PAK) compromises kidney allograft survival, and what pre-PAK glomerular filtration rate (GFR) should be used to select patients for PAK is unclear. We analyzed all (n = 2776) PAK recipients in the United States between 1989 and 2007 and compared their risk of kidney failure to a comparator group of n = 13 635 young adult diabetic kidney only transplant recipients during the same time after accounting for selection bias by the use of a propensity score for PAK in a multivariate time to event analysis. In a secondary analysis, we determined the association of pre-PAK GFR with subsequent kidney allograft survival. Despite an increased risk of death early after pancreas transplantation, PAK recipients had a decreased long-term risk of kidney allograft failure compared to diabetic kidney only transplant recipients HR = 0.89; 95% CI: [0.78-1.00]; p = 0.05. An association of pre-PAK GFR with kidney survival was not evident until 3 years after pancreas transplantation, and patients with a pre-PAK GFR of 30-39 mL/min still attained 10-year post-PAK kidney survival of 69%. We conclude that PAK is associated with improved kidney allograft survival, and pre-PAK GFR 30-39 mL/min should not preclude PAK. Expanded use of PAK is warranted.

The long-term quality of life of living kidney donors: a multicenter cohort study

Previous studies that described the long-term quality of life of living kidney donors were conducted in single centers, and lacked data on a healthy nondonor comparison group. We conducted a retrospective cohort study to compare the quality of life of 203 kidney donors with 104 healthy nondonor controls using validated scales (including the SF36, 15D and feeling thermometer) and author-developed questions. Participants were recruited from nine transplant centers in Canada, Scotland and Australia. Outcomes were assessed a median of 5.5 years after the time of transplantation (lower and upper quartiles of 3.8 and 8.4 years, respectively). 15D scores (scale of 0 to 1) were high and similar between donors and nondonors (mean 0.93 (standard deviation (SD) 0.09) and 0.94 (SD 0.06), p = 0.55), and were not different when results were adjusted for several prognostic characteristics (p = 0.55). On other scales and author-developed questions, groups performed similarly. Donors to recipients who had an adverse outcome (death, graft failure) had similar quality of life scores as those donors where the recipient did well. Our findings are reassuring for the practice of living transplantation. Those who donate a kidney in centers that use routine pretransplant donor evaluation have good long-term quality of life.

Ureteric sarcoidosis--a rare entity

Primary ureteric involvement in sarcoidosis is very rare; to our knowledge, only a few cases have been reported in the literature. We present here a rare case of ureteric sarcoidosis presenting with obstructive uropathy.

Religious beliefs, coping skills and responsibility to family as factors protecting against deliberate self-harm

<p><strong>Background.</strong> Deliberate self-harm (DSH) ranges from behaviours aiming to communicate distress or relieve tension, but where suicide is not intended, to actual suicide. Not all individuals are prone to DSH, which suggests that there are factors that protect against it. Identifying these could play an important role in the management and prevention of DSH.</p><p><strong>Objectives.</strong> This study examined whether religious beliefs, coping skills and responsibility to family serve as factors protecting against DSH in Kota Kinabalu, Sabah, Malaysia. <strong></strong></p><p><strong>Method.</strong> A cross-sectional comparative study assessed DSH patients consecutively admitted or directly referred to Queen Elizabeth General Hospital and Hospital Mesra Bukit Padang during the period December 2006 - April 2007. DSH patients (N=42) were matched with controls (N=42) for gender, age, religion, race, occupation and marital status. The DSH and control groups were compared using psychosocial tests that assess coping skills, religious beliefs and responsibility to family.</p><p><strong>Results.</strong> There were significant differences in religious beliefs (p=0.01) and responsibility to family (p=0.03) between the DSH patients and the control group. There were also significant differences in coping skills, DSH patients tending to use emotion-orientated coping (p=0.01) as opposed to task- and avoidance-orientated coping.<strong> </strong></p><p><strong>Conclusion.</strong> Consistent with international studies, coping skills (i.e. task-orientated skills), religious beliefs and responsibility to family were more evident in patients who did not attempt DSH than in those who did. These findings imply that treating DSH should not start only at the point of contact. Protective factors such as religious beliefs, responsibility to family and coping strategies can be inculcated from a very young age. However, caution is required in generalising the results owing to limitations of the study. Further extensive research on religious and psychotherapeutic interventions and prospective studies on protective factors will be helpful.</p>

The system of health insurance for living donors is a disincentive for live donation

The health insurance system for living donors is derived from insurance policies designed to cover accidental death or dismemberment. The system covers only the direct consequences of organ removal, and recoups the costs of related medical services from the transplant recipient's health insurance provider. The system forces transplant programs to differentiate between health services that are, or are not directly attributable to donation and may compromise the pretransplant evaluation, postoperative care and long-term care of living donors. The system is particularly problematic in the United States, where a significant proportion of donors do not have medical insurance. The requirement to assign donor costs to a particular recipient is poorly suited to facilitate advances in living donation such as the use of nondirected donors and living-donor paired exchange programs. We argue that given the current understanding regarding the long-term risks of living donation, the provision of basic medical insurance is a necessity for living donation and that the system of attributing donor costs to the recipient's insurance is inefficient, has the potential to undermine the care of living donors and is a disincentive to the expansion of living donation.

Cancer mortality in kidney transplantation

Immunosuppression is associated with an increased risk of cancer in kidney transplant recipients compared to the general population. It is less clear whether standardized cancer mortality ratios (SMRs) are also increased. This study's hypothesis is that SMRs are not increased because of competing risks of death. During the median follow-up of 5.05 years (Q1-Q3: 2.36-8.62), there were 1937 cancer deaths and 36 619 noncancer deaths among 164 078 first kidney-only transplant recipients captured in the United States Renal Data System between January 1990 and December 2004. The observed cancer death rate was 206 per 100 000 patient-years compared to an expected rate of 215 per 100,000 patient-years in the general population. The overall age- and sex-adjusted SMR was only 0.96 (95% CI 0.92-1.00). However, patients <50 years had SMRs significantly greater than unity while patients >60 had SMRs lower than unity. Up to 25% of cancer-related deaths occurred after allograft failure. These findings challenge the notion that cancer is a major cause of premature death in all kidney transplant recipients and has implications for design of cancer prevention strategies in kidney transplant recipients.

Recipient outcomes for expanded criteria living kidney donors: the disconnect between current evidence and practice

Older individuals or those with medical complexities are undergoing living donor nephrectomy more than ever before. Transplant outcomes for recipients of kidneys from these living expanded criteria donors are largely uncertain. We systematically reviewed studies from 1980 to June 2008 that described transplant outcomes for recipients of kidneys from expanded criteria living donors. Results were organized by the following criteria: older age, obesity, hypertension, reduced glomerular filtration rate (GFR), proteinuria and hematuria. Pairs of reviewers independently evaluated each citation and abstracted data on study and donor characteristics, recipient survival, graft survival, serum creatinine and GFR. Transplant outcomes for recipients of kidneys from older donors (> or =60 years) were described in 31 studies. Recipients of kidneys from older donors had poorer 5-year patient and graft survival than recipients of kidneys from younger donors [meta-analysis of 12 studies, 72% vs. 80%, unadjusted relative risk (RR) of survival 0.89, 95% confidence interval (CI) 0.83-0.95]. In meta-regression, this association diminished over time (1980s RR 0.79, 95% CI 0.65-0.96 vs. 1990s RR 0.91, 95% CI 0.85-0.99). Few transplant outcomes were described for other expanded criteria. This disconnect between donor selection and a lack of knowledge of recipient outcomes should give transplant decision-makers pause and sets an agenda for future research.

The pregnancy rate and live birth rate in kidney transplant recipients

Fertility is one of the potential benefits for women undergoing kidney transplantation; however, population-based information about the likelihood of pregnancy and successful fetal outcome is not available. In this observational study of 16 195 female kidney transplant recipients aged 15-45 years in the United States between 1990 and 2003, we determined the pregnancy rate and live birth rate using Medicare claims data from the first three posttransplant years. The pregnancy rate was 33 per thousand female transplant recipients between 1990 and 2003 and progressively declined from 59 in 1990 to 20 in 2000. The live birth rate between 1990 and 2003 was 19 per thousand female transplant recipients and declined in parallel with the pregnancy rate. Despite a decrease in therapeutic abortions over time, the proportion of pregnancies resulting in fetal loss (45.6%) remained constant during the study due to an increase in spontaneous abortions and other causes of fetal loss. The pregnancy rate in kidney transplant recipients was markedly lower and declined more rapidly than reported in the general American population during the same period. The live birth rate was substantially lower than reported in voluntary registries of transplant recipients, and the proportion of pregnancies resulting in unexpected fetal loss increased over time.

A subject-specific technique for respiratory motion correction in image-guided cardiac catheterisation procedures

We describe a system for respiratory motion correction of MRI-derived roadmaps for use in X-ray guided cardiac catheterisation procedures. The technique uses a subject-specific affine motion model that is quickly constructed from a short pre-procedure MRI scan. We test a dynamic MRI sequence that acquires a small number of high resolution slices, rather than a single low resolution volume. Additionally, we use prior knowledge of the nature of cardiac respiratory motion by constraining the model to use only the dominant modes of motion. During the procedure the motion of the diaphragm is tracked in X-ray fluoroscopy images, allowing the roadmap to be updated using the motion model. X-ray image acquisition is cardiac gated. Validation is performed on four volunteer datasets and three patient datasets. The accuracy of the model in 3D was within 5mm in 97.6% of volunteer validations. For the patients, 2D accuracy was improved from 5 to 13mm before applying the model to 2-4mm afterwards. For the dynamic MRI sequence comparison, the highest errors were found when using the low resolution volume sequence with an unconstrained model.

Deceased organ donation in Canada: an opportunity to heal a fractured system

There has been no significant increase in the number of deceased organ donors in Canada over the past decade. Canada's donation and transplant system will be restructured with the formation of a new national organization to oversee activity in provincially governed donation and transplantation services. We review the current status of deceased organ donation, highlight issues contributing to the current stagnation in donation and identify changes that will enable success in a new Canadian system. Determining Canada's organ donation performance is difficult because the data required to calculate meaningful metrics of donation performance are not available. Canadians wait longer for transplantation than Americans, and Canada is falling further behind the United States primarily because of fewer donations after cardiac death. The ongoing divide between intergovernmental jurisdictional domains limits national initiatives to improve Canada's donation system. The success of a new national system will be enabled by uniform provincial legislation to ensure that all patients are offered the option to donate, commitment of resources to support organ donation by provincial governments, transparent reporting of comparable metrics of donation performance, establishment of processes to introduce and implement new initiatives and alterations to reimbursement models for organ donation and recovery.

Nephrectomy after transplant failure: current practice and outcomes

The role of transplant nephrectomy after transplant failure is uncertain. We report the use and consequences of transplant nephrectomy among 19 107 transplant failure patients between 1995 and 2003 in the United States. Among 3707 patients with early transplant failure (graft survival <12 m), nephrectomy was performed in 56%, and was associated with an increased risk of death (HR 1.13, 95% CI 1.01-1.26). In contrast, among 15,400 patients with late transplant failure (graft survival > or =12 m), nephrectomy was performed in 27%, and was associated with a decreased risk of death (HR 0.89, 95% CI 0.83-0.95). In early transplant failure patients, nephrectomy was associated with a lower risk of repeat transplant failure (HR 0.72, 95% CI 0.56-0.94), while among late transplant failure patients; nephrectomy was associated with a higher risk of repeat transplant failure (HR 1.20, 95% CI 1.02-1.41). Definitive conclusions are not possible from this observational study. The role of nephrectomy in the management of dialysis treated transplant failure patients, and the implications of nephrectomy for repeat transplantation should be further studied in prospective studies.

Mortality of Canadians treated by peritoneal dialysis in remote locations

Patients residing in remote locations may be more likely to initiate peritoneal dialysis when starting renal replacement therapy to avoid relocation. These patients may have reduced access to medical care, however. To examine the hypothesis that patients residing some distance from their nephrologists would be more likely to select peritoneal dialysis but have an increased risk of mortality, we used prospectively collected data in a random sample of 26,775 patients initiating dialysis in Canada between 1990 and 2000. The distance between the patient's residence at dialysis inception and the practice location of their nephrologists was calculated. We used Cox proportional hazard models to determine the adjusted relation between this distance and clinical outcomes over a mean follow-up period of 2.5 years up to 14 years. Remote-dwelling patients were more likely than urban dwellers to commence peritoneal dialysis in distances ranging from 50 to greater than 300 km than those residing within 50 km. The adjusted rates of death and the adjusted hazard ratio among patients initiating peritoneal dialysis was significantly higher in those living further from the nephrologists than those living within 50 km. Further study into the quality of care delivered to remote-dwelling patients on peritoneal dialysis is needed.

Patient and allograft survival of Indo Asian and East Asian dialysis patients treated in Canada

Kidney failure is relatively common among Canadians of Asian origin. However, little is known about the health outcomes after initiation of renal replacement therapy in this population. Our study evaluates differences in the likelihood of renal transplantation and graft loss among Asian and white patients. We studied 21 523 adults of East Asian, Indo Asian or white ethnicity who had initiated dialysis in Canada from 1990-2000. Subjects were followed until death, loss to follow-up or end of study (2004). The proportion of the eligible subjects who were East Asian, Indo Asian, or white was 6, 3, and 91%, respectively. Compared to white patients, East Asian and Indo Asian patients were significantly less likely to receive a renal transplant after adjusting for potential confounding factors. This disparity is greater for transplants from living donors as compared to those from deceased donors. The adjusted death censored graft loss in transplant recipients was not significantly different between ethnic groups. The adjusted risk of death following transplantation, however, was significantly lower in Indo Asian than in white patients. Our findings show that in a Canadian population, patients of East Asian or Indo Asian origin had lower rates of renal transplantation than white patients, especially for living donor transplantation. These findings warrant further study, especially given the good graft outcomes in these individuals.

The importance of transitions between dialysis and transplantation in the care of end-stage renal disease patients

Analyses describing outcomes of kidney transplantation usually exclude the survival of wait-listed patients and dialysis patients with failed kidney transplants, and thus reflect only a portion of the typical transplant process. We determined death rates during the continuum of wait-listing, transplantation, and after allograft failure among adult end-stage renal disease patients in the United States between 1995 and 2003. Before transplantation, death rates increased with longer waiting times. Death rates were lowest during the period of allograft function and highest after allograft failure. Patients were at particularly high risk during periods of transition between dialysis and transplantation (death rates during the peri-transplant period and during the re-initiation of dialysis after transplant failure were 8.2/100 patient-years (95% confidence interval (CI) 7.7, 8.8) and 17.9/100 patient-years (95% CI 15.7, 20.3), respectively compared to 6.4/100 patient-years (95% CI 6.25, 6.51) during the period of wait-listing. Diabetic patients and older patients were at increased risk at all time points. The most common known cause of death in all age subgroups was cardiovascular disease. The proportion of death owing to sepsis was greatest after allograft failure (16.8% of all deaths were due to sepsis compared to 14.0% during wait-listing, and 12.7% during the period of allograft function). Consideration of the entire transplant experience as a whole should help to focus patient care on periods of particularly high risk, and emphasizes opportunities to improve outcomes by strategies aimed at preventing death owing to cardiovascular and infectious causes.

Epoetin use and Kidney Disease Outcomes Quality Initiative hemoglobin targets in patients returning to dialysis with failed renal transplants

Patients with failed renal transplants represent an increasing proportion of the current dialysis population. Although their risk of anemia might be expected to be high, whether these patients receive adequate anemia therapy after returning to dialysis is unknown. We studied intravenous iron use, epoetin doses, and hemoglobin levels in patients with and without failed renal transplants who survived for 6 months after initiation of dialysis in the United States between 1996 and 2001. Of the study population (n=220 557), 9922 (4.5%) had failed renal transplants. In spite of a greater likelihood of receiving intravenous iron therapy (adjusted odds ratio (AOR) 1.47, P<0.0001) and epoetin (AOR 1.57, P<0.0001), patients with failed transplants were more anemic and had higher epoetin doses in each month of follow-up. During month 6, patients with failed transplants were more likely to have hemoglobin levels below 11 g/dl (AOR 1.50, P<0.0001) and to have epoetin-to-hemoglobin ratios above the population median of 1030 U/week per g/dl (AOR 1.73, P<0.0001). Patients who return to dialysis with failed transplants are at a higher risk of anemia than other patients who start dialysis; the pattern of lower hemoglobin levels and higher ratios of epoetin-to-hemoglobin suggests that relative epoetin resistance may be contributory.

Potential advantages and limitations of applying the chronic kidney disease classification to kidney transplant recipients

The National Kidney Foundation (NKF) Kidney Disease Outcomes Quality Initiative (K/DOQI) classification of Chronic Kidney Disease (CKD) characterizes patients by their level of kidney function and includes kidney transplant recipients (KTRs). Most KTRs have stage > or = 3 CKD (estimated glomerular filtration rate < 60 mL/min/1.73 m2) and may benefit from aggressive CKD care. Recent modifications to the K/DOQI CKD classification reflect the recognition of KTRs as a unique subset of CKD patients in whom the presentation, progression and implications of CKD may vary from those in nontransplant CKD populations. Currently, there is limited information about how adopting the CKD classification in KTRs will influence clinical management and outcomes. Appropriately designed studies are needed to develop transplant-specific CKD treatment recommendations, and to ensure patient, health provider and payer acceptance of the continued need for aggressive CKD care after transplantation. Education and implementation strategies will be required to ensure appropriate integration of the CKD classification and treatment guidelines into existing posttransplant care programs. The CKD classification thus represents an exciting potential strategy to improve clinical outcomes that should be adopted, further studied and modified to incorporate considerations unique to KTRs.

Association between residence location and likelihood of kidney transplantation in Aboriginal patients treated with dialysis in Canada

For reasons that are not well understood, Aboriginal people with end-stage renal disease (ESRD) have lower rates of kidney transplantation. We hypothesized that distance between residence location and the closest transplant center was greater in Aboriginal dialysis patients and would partially explain the lower rate of transplantation in this population. We studied a random sample of 9905 patients initiating dialysis in Canada between 1990 and 2000. We calculated the distance between residence location at dialysis inception and the closest transplant center. Cox proportional hazards models were used to examine the relation between residence location and the likelihood of transplantation over a median period of 2.3 years. The proportion of Aboriginal participants living <or=50, 50.1-150, 150.1-300, and >300 km from the closest transplant center was 25, 18, 18, and 39% respectively, compared with 55, 19, 11, and 15% among white subjects. The relative likelihood of transplantation was significantly lower for Aboriginal compared to white participants across all four distance strata, with no apparent effect of residence location. For example, the relative likelihood of transplantation was hazard ratio (HR) 0.47, 95% confidence interval (CI) (0.31-0.72) in Aboriginal participants residing <or=50 and 0.55 (0.38-0.80) in those residing >300 km from the closest transplant center. Results were similar for transplants from deceased donors and living donors, and in all seven regions studied. In conclusion, remote location of residence does not explain the lower rate of kidney transplantation among Aboriginal people treated for ESRD in Canada.