A2/A2B to B kidney transplantation outcomes: A single center 7-year experience

INTRODUCTION

Data on long-term outcomes following A2/A2B to B kidney transplants since the 2014 kidney allocation system (KAS) changes are few. The primary aim of this study is to report our 7-year experience with A2/A2B to B kidney transplants and to compare post-transplant outcomes of A2/A2B to a concurrent group of B to B kidney transplants. Additionally, the study evaluates the impact of pre-transplant anti-A1 titers on survival outcomes in A2/A2B transplants.

METHODS

This retrospective, single-center analysis included all adults who received A2/A2B to B deceased donor kidney transplants from December 2014 to June 2021 compared to B to B recipients. The effects of pre-transplant IgM/IgG titers, stratified as ≤1:8 and ≥1:16, on death-censored, rejection-free, and overall graft survival were tested.

RESULTS

Fifty-three A2/A2B and 114 B to B adults were included with a median follow-up time of 32 months. Overall graft survival, patient survival, and rejection-free graft survival did not differ between the two groups. There were no differences between the groups' overall kidney function values (p > .80) or their temporal trajectories (time by group interaction p > .11). Unadjusted death-censored graft survival was lower in A2/A2B to B compared to B recipients (p = .03), but the effect was not significant (p = .195) after adjusting for any readmissions (p = .96), rejection episodes (p < .001) or BK infection (p = .76). We did not detect an effect of pre-transplant titer group on death-censored (p = .59), rejection-free (p = .61), or overall graft survival (p = .26) CONCLUSIONS: A2/A2B to B kidney transplants have comparable overall patient and graft survival, rejection-free graft survival, and longitudinal renal function compared to B to B transplants at our center. Allograft survival outcomes were not significantly different between patients with low and high pre-transplant anti-A1 IgM/IgG titers.

Impact of Social Media on Self-Referral Patterns for Living Kidney Donation

Background

As the organ-shortage crisis continues to worsen, many patients in need of a kidney transplant have turned to social media to find a living donor. The effect of social media on living kidney donation is not known. The goal of this study is to investigate the influence of social media on those interested in donating a kidney.

Methods

Self-referrals for living kidney donation from December 2016 to March 2019 were retrospectively reviewed. Age, sex, race, and relationship of individuals petitioned through social media (SM) were compared with those petitioned through verbal communication (VC). Data were analyzed using chi-squared tests, with z tests of column proportions, and multivariable logistic regression.

Results

A total of 7817 individuals (53% SM, 36% VC, and 10% other) were self-referred for living kidney donation. The analysis sample included 6737 adults petitioned through SM (n=3999) or VC (n=2738). Half (n=3933) of the individuals reported an altruistic relationship, and 94% of these respondents were petitioned through SM. Although univariate analyses indicated that SM respondents were younger, more likely female, more likely White, and more likely to have directed altruistic intent than those petitioned through VC (all P<0.05), multivariable logistic regression demonstrated that only decreased age, female sex, and relationship were significantly related to likelihood of SM use (all P<0.001).

Conclusions

The use of SM to petition living kidney donors is prevalent and accounts for a greater proportion of respondents compared with VC. SM respondents tend to be younger, female, and altruistic compared with VC. Directed altruistic interest in kidney donation is almost exclusively generated through SM.

Care of international living kidney donor candidates in the United States: A survey of contemporary experience, practice, and challenges

The evaluation and care of non-US citizen, non-US residents who wish to come to the United States to serve as international living kidney donors (ILKDs) can pose unique challenges. We surveyed US transplant programs to better understand practices related to ILKD care. We distributed the survey by email and professional society list-servs (Fall 2018, assessing 2017 experience). Eighty-five programs responded (36.8% program response rate), of which 80 considered ILKD candidates. Only 18 programs had written protocols for ILKD evaluation. Programs had a median of 3 (range: 0,75) ILKD candidates who initiated contact during the year, from origin countries spanning 6 continents. Fewer (median: 1, range: 0,25) were approved for donation. Program-reported reasons for not completing ILKD evaluations included visa barriers (58.6%), inability to complete evaluation (34.3%), concerns regarding follow-up (31.4%) or other healthcare access (28.6%), and financial impacts (21.4%). Programs that did not evaluate ILKDs reported similar concerns. Staff time required to evaluate ILKDs was estimated as 1.5-to-3-times (47.9%) or >3-times (32.9%) that needed for domestic candidates. Among programs accepting ILKDs, on average 55% reported successful completion of 1-year follow-up. ILKD evaluation is a resource-intensive process with variable outcomes. Planning and commitment are necessary to care for this unique candidate group.

The effect of pulsatile pump perfusion on hepatitis C transmission in kidney transplantation: A prospective pilot study

With increasing utilization of hepatitis C (HCV) viremic donor organs, there may be a role for kidney pump perfusion to reduce viral load and prevent HCV transmission. We performed a prospective pilot study of HCV viremic donors; one kidney from each donor pair was pumped with perfusate exchanges and viral load testing at least every 4 hours. Donor, recipient, and transplant characteristics were obtained with clinical outcomes. Linear regression was performed to quantify the association between pump time and perfusate viral load. Six HCV viremic donors for six pairs of aviremic recipients were included. Perfusate of the pumped kidneys showed detectable virus throughout the pump cycles. Although perfusate viral levels decreased with increasing pump times, this was not statistically significant (β = -.48, P = .36). All recipients had detectable HCV RNA postoperatively. The pumped cohort had an insignificantly reduced mean viral load compared to pumped recipients (1352 ± 2006 vs 26 170 ± 61 211, P = .09). Time to initiation of direct-acting antiviral was 32 ± 12 vs 26 ± 7 days (P = .17) and to undetectable levels was 66 ± 27 vs 55 ± 22 days (P = .82) for the pumped and unpumped cohorts, respectively. Pulsatile perfusion alone does not appear adequate to decrease HCV transmission. Future studies will need to explore additional ex vivo interventions to pumping.

A2 to B Blood Type Incompatible Deceased Donor Kidney Transplantation in a Recipient Infected with the Human Immunodeficiency Virus: A Case Report

BACKGROUND

With the introduction of the Kidney Allocation System in the United States in December 2014, transplant centers can list eligible B blood type recipients for A2 organ offers. There have been no prior reports of ABO incompatible A2 to B deceased donor kidney transplantation in human immunodeficiency virus-positive (HIV+) recipients to guide clinicians on enrolling or performing A2 to B transplantations in HIV+ candidates. We are the first to report a case of A2 to B deceased donor kidney transplantation in an HIV+ recipient with good intermediate-term results.

METHODS AND RESULTS

We describe an HIV+ 39-year-old African American man with end-stage renal disease who underwent A2 to B blood type incompatible deceased donor kidney transplantation. Prior to transplantation, he had an undetectable HIV viral load. The patient was unsensitized, with his most recent anti-A titer data being 1:2 IgG and 1:32 IgG/IgM. Induction therapy of basiliximab and methylprednisolone was followed by a postoperative regimen of plasma exchange, intravenous immunoglobulin, and rituximab with maintenance on tacrolimus, mycophenolate mofetil, and prednisone. He had delayed graft function without rejection on allograft biopsy. Nadir serum creatinine was 2.0 mg/dL. He continued to have an undetectable viral load on the same antiretroviral therapy adjusted for renal function.

CONCLUSIONS

To our knowledge, this is the first report of A2 to B deceased donor kidney transplantation in an HIV+ recipient with good intermediate-term results, suggesting that A2 donor kidneys may be considered for transplantation into HIV+ B-blood type wait list candidates.

Older candidates for kidney transplantation: Who to refer and what to expect?

The number of older end-stage renal disease patients being referred for kidney transplantation continues to increase. This rise is occurring alongside the continually increasing prevalence of older end-stage renal disease patients. Although older kidney transplant recipients have decreased patient and graft survival compared to younger patients, transplantation in this patient population is pursued due to the survival advantage that it confers over remaining on the deceased donor waiting list. The upper limit of age and the extent of comorbidity and frailty at which transplantation ceases to be advantageous is not known. Transplant physicians are therefore faced with the challenge of determining who among older patients are appropriate candidates for kidney transplantation. This is usually achieved by means of an organ systems-based medical evaluation with particular focus given to cardiovascular health. More recently, global measures of health such as functional status and frailty are increasingly being recognized as potential tools in risk stratifying kidney transplant candidates. For those candidates who are deemed eligible, living donor transplantation should be pursued. This may mean accepting a kidney from an older living donor. In the absence of any living donor, the choice to accept lesser quality kidneys should be made while taking into account the organ shortage and expected waiting times on the deceased donor list. Appropriate counseling of patients should be a cornerstone in the evaluation process and includes a discussion regarding expected outcomes, expected waiting times in the setting of the new Kidney Allocation System, benefits of living donor transplantation and the acceptance of lesser quality kidneys.

Investment in attending to cues and the evolution of amplifiers

Signals and cues are extensively used in social interactions across diverse communication systems. Here, we extend an existing theoretical framework to explore investment by emitters and perceivers in the fidelity with which cues and signals associated with the former are detected by the latter. Traits of the emitter that improve cue or signal fidelity without adding information are termed 'amplifiers'. We assume that each party can invest in improving fidelity but that it is increasingly costly the more fidelity is improved. Our model predicts that evolution of amplifier traits of a pre-existing cue occurs over a broader range of circumstances than evolution of signalling in situations where the emitter offered no pre-existing cue to the perceiver. It further predicts that the greater the intrinsic informational value of a cue, the more likely it is that the perceiver (and not the emitter) will invest in the fidelity of detecting that cue. A consequence of this predicted asymmetry is that true communication with reciprocal adaptations in emitters and perceivers to improve signal fidelity is likely to occur predominantly for traits of intermediate reliability. The corollary is that uncertainty of the perceiver will then be a key feature of communication. Uncertainty can arise because perceivers misinterpret signals or do not perceive them correctly, but here we argue that uncertainty is more fundamentally at the root of communication because traits that are intrinsically highly informative will induce only the perceiver and not the emitter to invest in improved fidelity of perception of that trait.

Evaluating the Impact of Performance Improvement Initiatives on Transplant Center Reporting Compliance and Patient Follow-Up After Living Kidney Donation

With the changing demographics of the living donor population and increased regulatory oversight, it is important that transplant centers report outcomes accurately. The aim of our retrospective cohort study of 312 living donors who underwent nephrectomy between 2008 and 2013 was to evaluate the impact of living donor program performance improvement initiatives on: (i) transplant center program reporting compliance; (ii) patient compliance with postdonation follow-up and its associated factors; and (iii) overall financial costs to the transplant center. The effect of the initiatives (donation eras 2008-2010 and 2011-2013) on compliance at key reporting points (6 months, 1 year, 2 years) was analyzed using correlation coefficients, χ(2) and Fisher's exact tests. Multivariable logistic regression models tested the initiatives' effect on the likelihood of patient follow-up. The initiatives were associated with significant improvement in form reporting compliance (r ≥ 0.862, p ≤ 0.027; 1 and 2 year Fisher's Exact p ≤ 0.002) and patient follow-up (χ(2) p ≤ 0.009) with acceptable transplant center costs. Multivariable analyses demonstrated that donation era was consistently and significantly (p < 0.001) associated with increased likelihood of postdonation patient follow-up. Institution of performance improvement initiatives with dedicated program resources is financially feasible and leads to more accurate and complete form reporting and improved patient follow-up after nephrectomy.

Selection on quantitative colour variation in Centaurea cyanus: the role of the pollinator's visual system

Even though the importance of selection for trait evolution is well established, we still lack a functional understanding of the mechanisms underlying phenotypic selection. Because animals necessarily use their sensory system to perceive phenotypic traits, the model of sensory bias assumes that sensory systems are the main determinant of signal evolution. Yet, it has remained poorly known how sensory systems contribute to shaping the fitness surface of selected individuals. In a greenhouse experiment, we quantified the strength and direction of selection on floral coloration in a population of cornflowers exposed to bumblebees as unique pollinators during 4 days. We detected significant selection on the chromatic and achromatic (brightness) components of floral coloration. We then studied whether these patterns of selection are explicable by accounting for the visual system of the pollinators. Using data on bumblebee colour vision, we first showed that bumblebees should discriminate among quantitative colour variants. The observed selection was then compared to the selection predicted by psychophysical models of bumblebee colour vision. The achromatic but not the chromatic channel of the bumblebee's visual system could explain the observed pattern of selection. These results highlight that (i) pollinators can select quantitative variation in floral coloration and could thus account for a gradual evolution of flower coloration, and (ii) stimulation of the visual system represents, at least partly, a functional mechanism potentially explaining pollinators' selection on floral colour variants.

Reproductive success depends on the quality of helpers in the endangered, cooperative El Oro parakeet (Pyrrhura orcesi)

In cooperative species, helping behaviour and reproductive success can be correlated, but understanding this correlation is often impaired by the difficulty to correctly infer causation. While helpers can incur costs by participating in brood care, it is yet unclear if their help depends on their individual quality. We address these questions in the previously unknown cooperative breeding system of the endangered El Oro parakeet (Pyrrhura orcesi). Specifically, we ask (i) whether breeders benefit directly from helpers by an enhanced reproductive success and if so, (ii) whether the amount of this potential benefit is regulated by the quality of contributing group members. Groups consist of a dominant breeding pair accompanied by helpers, but cooperation is not obligate. Microsatellite heterozygosity was used to assess individual quality; its suitability as indicator of quality was reflected in the positive relationship between offspring heterozygosity and recruitment into the population. The reproductive success of breeding pairs depended on helper (genetic) quality and the number of helpers. This relationship occurred on two different levels: clutch size and fledging success, indicating (i) that females profit from high-quality helpers and probably adjust clutch size accordingly and (ii) that the helpers increase fledging success. Congruently, we found that offspring body condition is positively affected by helper quality, which is most probably explained by the increased feeding rates when helpers are present. We suggest a causal link between cooperation and reproductive success in this frugivorous, endangered parakeet. Further, helper (genetic) quality can be a relevant factor for determining reproductive fitness in cooperative species, particularly in small and bottlenecked populations.

Critical and honest conversations: the evidence behind the "Choosing Wisely" campaign recommendations by the American Society of Nephrology

Estimates suggest that one third of United States health care spending results from overuse or misuse of tests, procedures, and therapies. The American Board of Internal Medicine Foundation, in partnership with Consumer Reports, initiated the "Choosing Wisely" campaign to identify areas in patient care and resource use most open to improvement. Nine subspecialty organizations joined the campaign; each organization identified five tests, procedures, or therapies that are overused, are misused, or could potentially lead to harm or unnecessary health care spending. Each of the American Society of Nephrology's (ASN's) 10 advisory groups submitted recommendations for inclusion. The ASN Quality and Patient Safety Task Force selected five recommendations based on relevance and importance to individuals with kidney disease.Recommendations selected were: (1) Do not perform routine cancer screening for dialysis patients with limited life expectancies without signs or symptoms; (2) do not administer erythropoiesis-stimulating agents to CKD patients with hemoglobin levels ≥10 g/dl without symptoms of anemia; (3) avoid nonsteroidal anti-inflammatory drugs in individuals with hypertension, heart failure, or CKD of all causes, including diabetes; (4) do not place peripherally inserted central catheters in stage 3-5 CKD patients without consulting nephrology; (5) do not initiate chronic dialysis without ensuring a shared decision-making process between patients, their families, and their physicians.These five recommendations and supporting evidence give providers information to facilitate prudent care decisions and empower patients to actively participate in critical, honest conversations about their care, potentially reducing unnecessary health care spending and preventing harm.

Permanent Genetic Resources added to the Molecular Ecology Resources Database 1 February 2010-31 March 2010

This article documents the addition of 228 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Anser cygnoides, Apodemus flavicollis, Athene noctua, Cercis canadensis, Glis glis, Gubernatrix cristata, Haliotis tuberculata, Helianthus maximiliani, Laricobius nigrinus, Laricobius rubidus, Neoheligmonella granjoni, Nephrops norvegicus, Oenanthe javanica, Paramuricea clavata, Pyrrhura orcesi and Samanea saman. These loci were cross-tested on the following species: Apodemus sylvaticus, Laricobius laticollis and Laricobius osakensis (a proposed new species currently being described).

Dietary flavonoids enhance conspicuousness of a melanin-based trait in male blackcaps but not of the female homologous trait or of sexually monochromatic traits

Signalling theory predicts that signals should fulfil three fundamental requirements: high detectability, discriminability and, most importantly, reliability. Melanins are the most common pigments in animals. Correlations between genotypic and phenotypic qualities of the sender and size and morph of melanin-based traits are known, but it is contentious whether melanin-based colouration may signal any quality. We examined the effect of supplementing blackcaps (Sylvia atricapilla) with flavonoids, potent plant antioxidants, on plumage colouration. We demonstrate that melanin-based colour can fulfil all requirements of signals of phenotypic condition. As predicted by sexual selection theory, flavonoid supplementation influenced only the sexually dichromatic black cap of males, whereas the female homologous trait and the sexually monochromatic back colouration remained unaffected. Using avian vision models we show that birds can estimate male flavonoid intake from colouration of males' black cap. Because flavonoid ingestion can increase immune responsiveness in blackcaps, melanin head colouration may signal environmentally determined immune condition.

Serum sickness following rabbit antithymocyte-globulin induction in a liver transplant recipient: case report and literature review

Thymoglobulin (Genzyme, Cambridge, MA) is an antithymocyte globulin preparation used for induction immunosuppression therapy in solid organ transplantation. It is being utilized with increasing frequency in orthotopic liver transplantation (OLT) in an effort to minimize or delay the use of calcineurin inhibitors due to their inherent nephrotoxicity. Experience with thymoglobulin in OLT remains limited. We report a case of serum sickness in a patient who received thymoglobulin following OLT. The patient experienced intermittent fevers, polyarthralgia, and acute renal failure 9 days after completion of thymoglobulin administration. The patient's symptoms resolved rapidly and completely with a course of intravenous steroids. We review a set of diagnostic criteria for serum sickness and emphasize the importance of early recognition of the process. Early treatment of serum sickness with steroids or plasmapheresis is highly effective and can reduce unnecessary morbidity from this unusual sequela of induction immunosuppression with antithymocyte globulin.

Calcineurin Inhibitor Avoidance Versus Steroid Avoidance Following Kidney Transplantation: Postoperative Complications

This study compared early postoperative complications in kidney transplant recipients treated with either a sirolimus-based calcineurin inhibitor (CNI)-free regimen or a tacrolimus-based steroid-free regimen. We used a single-center, prospective, sequential but nonrandomized study design. Consecutive recipients of primary cadaveric or non-HLA identical kidney transplant recipients received either a CNI-free regimen, consisting of sirolimus 5 mg daily beginning postoperative day 3, mycophenolate mofetil 1 gm twice a day, and methylprednisolone 500 mg intraoperatively, then prednisone 30 mg daily tapered to 10 mg daily at 3 months, or a prednisone-free regimen, consisting of methylprednisolone 500 mg, 250 mg, and 125 mg from days 0 to 2, then no further steroids, tacrolimus 0.075 mg/kg twice a day, and mycophenolate mofetil 1 g twice a day. All patients received thymoglobulin induction 6 mg/kg total dose. Outcome measures were patient and graft survival, BPAR, surgical and wound complications, viral infections and posttransplant diabetes mellitus (PTDM). Both groups had excellent early outcomes with no significant difference in patient or graft survival, early renal function, BPAR, surgical or wound complications, or viral infections between the two groups. Patients in the sirolimus-based CNI-free group had a significantly higher incidence of PTDM and a trend toward more discontinuation due to drug toxicity. Whether either regimen improves long-term outcomes awaits longer follow-up.

Short-term Results Under Three Different Immunosuppressive Regimens at One Center

We examined short-term outcomes and posttransplant medical complications under three different immunosuppressive regimens at a single center. The study design was a randomized, prospective, open-label trial comparing a calcineurin inhibitor-free (CNI) protocol to standard triple therapy with tacrolimus, prednisone, and mycophenolate mofetil. They were also compared to a concurrent but nonrandomized third cohort treated with a prednisone-free protocol. All three groups had excellent early outcomes with no significant difference in patient or graft survival or biopsy-proven acute rejection. Serum creatinine was significantly lower in the CNI-free recipients. Lipid panels and posttransplant diabetes mellitus were significantly lower in the prednisone-free patients. Prednisone-free kidney transplant recipients have improved early glucose metabolism and hyperlipidemia compared to CNI-free or standard triple therapy recipients with comparable rejection and graft survival rates.