Shared Decision-Making in Kidney Patients: Involvement in Decisions Regarding the Quality of Deceased Donor Kidneys

OBJECTIVES

This study examined whether kidney patients want to participate in decisions regarding the minimal acceptable quality of deceased donor kidneys. We also explored patients' opinions about the trade-off between a higher-quality organ with a longer waiting time vs a lower-quality organ with a shorter waiting time.

METHODS

A questionnaire was distributed among kidney patients. Additionally, a sub-sample of these patients participated in in-depth interviews, which were analyzed using the grounded theory approach.

RESULTS

Sixty-three percent of the patients wished to participate in decisions concerning the quality of a deceased donor kidney. The majority of the respondents indicated that they prefer a kidney of good quality and would therefore accept a longer waiting time. Responses to the qualitative interviews illustrated a more balanced choice regarding this trade-off.

CONCLUSIONS

Many patients wish to be involved in deciding on the quality of the kidney, but it may evoke the experience of decisional conflicts when they have to make rational trade-offs between the desire for the best kidney at the expense of a longer waiting time.

Differential effects of donor-specific HLA antibodies in living versus deceased donor transplant

The presence of donor-specific anti-HLA antibodies (DSAs) is associated with increased risk of graft failure after kidney transplant. We hypothesized that DSAs against HLA class I, class II, or both classes indicate a different risk for graft loss between deceased and living donor transplant. In this study, we investigated the impact of pretransplant DSAs, by using single antigen bead assays, on long-term graft survival in 3237 deceased and 1487 living donor kidney transplants with a negative complement-dependent crossmatch. In living donor transplants, we found a limited effect on graft survival of DSAs against class I or II antigens after transplant. Class I and II DSAs combined resulted in decreased 10-year graft survival (84% to 75%). In contrast, after deceased donor transplant, patients with class I or class II DSAs had a 10-year graft survival of 59% and 60%, respectively, both significantly lower than the survival for patients without DSAs (76%). The combination of class I and II DSAs resulted in a 10-year survival of 54% in deceased donor transplants. In conclusion, class I and II DSAs are a clear risk factor for graft loss in deceased donor transplants, while in living donor transplants, class I and II DSAs seem to be associated with an increased risk for graft failure, but this could not be assessed due to their low prevalence.

How can we reduce costs of solid-phase multiplex-bead assays used to determine anti-HLA antibodies?

Solid-phase multiplex-bead assays are widely used in transplantation to detect anti-human leukocyte antigen (HLA) antibodies. These assays enable high resolution detection of low levels of HLA antibodies. However, multiplex-bead assays are costly and yield variable measurements that limit the comparison of results between laboratories. In the context of a Dutch national Consortium study we aimed to determine the inter-assay and inter-machine variability of multiplex-bead assays, and we assessed how to reduce the assay reagents costs. Fifteen sera containing a variety of HLA antibodies were used yielding in total 7092 median fluorescence intensities (MFI) values. The inter-assay and inter-machine mean absolute relative differences (MARD) of the screening assay were 12% and 13%, respectively. The single antigen bead (SAB) inter-assay MARD was comparable, but showed a higher lot-to-lot variability. Reduction of screening assay reagents to 50% or 40% of manufacturers' recommendations resulted in MFI values comparable to 100% of the reagents, with an MARD of 12% or 14%, respectively. The MARD of the 50% and 40% SAB assay reagent reductions were 11% and 22%, respectively. From this study, we conclude that the reagents can be reliably reduced at least to 50% of manufacturers' recommendations with virtually no differences in HLA antibody assignments.

Controlled donation after circulatory death in the Netherlands: more organs, more efforts

BACKGROUND

The Netherlands was one of the first countries in Europe to stimulate controlled donation after circulatory death (cDCD) at a national level in addition to donation after brain death (DBD). With this program the number of organ transplants increased, but it also proved to have challenges as will be shown in this 15-year review.

METHODS

Data about deceased organ donation in the Netherlands, from 2000 until 2014, were analysed taking into account the whole donation process from donor referral to the number of organs transplanted.

RESULTS

Donor referral increased by 58%, from 213 to 336 donors per year, and the number of organs transplanted rose by 42%. Meanwhile the contribution of cDCD donors increased from 14% in 2000 to 54% in 2014 among all referrals. The organs were transplanted from 92-99% of referred DBD donors, but this percentage was significantly lower for cDCD donors and also decreased from 86% in 2000-2002 to 67% in 2012-2014. In 16% of all referred cDCD donors, organs were not recovered because donors did not die within the expected two-hour time limit after withdrawal of life- upporting treatment. Furthermore, cDCD is more often performed at a higher donor age, which is associated with a lower percentage of transplanted organs.

CONCLUSION

Although cDCD resulted in more transplants, the effort in donor recruitment is considerably higher. Important challenges in cDCD that need further attention are the time limit after withdrawal of life-supporting treatment and donor age, as well as the possibilities to stimulate non-renal transplants including the heart by machine preservation.

The natural history of clinical operational tolerance after kidney transplantation through twenty-seven cases

We report here on a European cohort of 27 kidney transplant recipients displaying operational tolerance, compared to two cohorts of matched kidney transplant recipients under immunosuppression and patients who stopped immunosuppressive drugs and presented with rejection. We report that a lower proportion of operationally tolerant patients received induction therapy (52% without induction therapy vs. 78.3%[p = 0.0455] and 96.7%[p = 0.0001], respectively), a difference likely due to the higher proportion (18.5%) of HLA matched recipients in the tolerant cohort. These patients were also significantly older at the time of transplantation (p = 0.0211) and immunosuppression withdrawal (p = 0.0002) than recipients who rejected their graft after weaning. Finally, these patients were at lower risk of infectious disease. Among the 27 patients defined as operationally tolerant at the time of inclusion, 19 still display stable graft function (mean 9 ± 4 years after transplantation) whereas 30% presented slow deterioration of graft function. Six of these patients tested positive for pre-graft anti-HLA antibodies. Biopsy histology studies revealed an active immunologically driven mechanism for half of them, associated with DSA in the absence of C4d. This study suggests that operational tolerance can persist as a robust phenomenon, although eventual graft loss does occur in some patients, particularly in the setting of donor-specific alloantibody.

The pharmacokinetic-pharmacodynamic relationship for mycophenolate mofetil in renal transplantation

BACKGROUND

Mycophenolate mofetil, a pro-drug for mycophenolic acid, reduces the likelihood of allograft rejection after renal transplantation. We studied the relationship between mycophenolic acid pharmacokinetics and the likelihood of rejection in a randomized concentration-controlled trial.

METHODS

Under double-blind conditions, recipients of kidney transplants were followed for evidence of allograft rejection for 6 months. In addition to mycophenolate mofetil, patients received usual doses of cyclosporine (INN, ciclosporin) and corticosteroids. The dose of mycophenolate mofetil (given twice daily) was controlled by feedback, with mycophenolic acid area under the concentration-time curve (AUC) as the controlled variable. Patients were randomly assigned to 1 of 3 target AUC groups.

RESULTS

Logistic regression analysis showed a significant (P < .0001) relationship between mycophenolic acid AUC and the likelihood of rejection. High mycophenolic acid values were associated with a very low probability of rejection. An AUC of 15 micrograms.h/mL yielded 50% of maximal achievable efficacy with a 4% change of efficacy for a 1 microgram.h/mL change in AUC at the midpoint of the logistic curve. Exploratory analyses showed other variables (e.g., the maximum observed plasma concentration, predose plasma concentration, and drug dose) had poorer predictive power for the rejection outcome. Bivariate regression confirmed the importance of AUC as a highly predictive variable and showed low predictive value of other variables, once the contribution of AUC had been considered. The characteristic side effects of mycophenolate mofetil therapy appeared related to drug dose but not to mycophenolic acid concentration.

CONCLUSIONS

The AUC of mycophenolic acid is predictive of the likelihood of allograft rejection after renal transplantation in patients receiving mycophenolate mofetil.

Immune hemolytic anemia associated with tolmetin and suprofen

This article reports the first case of immune hemolytic anemia possibly associated with the ingestion of suprofen. The patient suffered from massive hemoglobinuria and acute renal failure. Serologic studies of the patient's serum revealed suprofen-dependent red cell antibodies. However, tolmetin-dependent antibodies were also found in the serum, showing the same properties as the suprofen antibodies and an even higher titer. The patient not only had drug-dependent antibodies in the serum, but also had developed autoantibodies, a phenomenon that has been described for several other drugs. The working mechanism by which suprofen and tolmetin caused immune hemolysis had properties of both the immune complex model and the induction of autoimmunity. Although it was unclear whether the immune hemolytic anemia was the result of suprofen, tolmetin, or cross-reacting antibodies, we feel that suprofen should be added to the list of nonsteroidal anti-inflammatory drugs associated with a positive direct antiglobulin test.

The effect of alpha-human atrial natriuretic peptide on the incidence of acute renal failure in cadaveric kidney transplantation

In previous studies in humans, mannitol (20%, 250 ml) has been shown to reduce the incidence of acute renal failure (ARF) after transplantation from 54% to 19%. In rats, atrial natriuretic peptide appears to prevent ischemia-induced ARF. We therefore decided to evaluate the effects of alpha-human atrial natriuretic peptide (alpha-h-ANP) both alone and combined with mannitol during transplantation in humans. First, we demonstrated that systemic alpha-h-ANP infusion during kidney transplantation was safe in dosages up to 0.08 micrograms/kg per minute. In these patients the calculated metabolic clearance rate of alpha-h-ANP was relatively low ranging from 0.68 to 1.80 l/min. In a second study of 11 renal graft recipients, no mannitol was used and alpha-h-ANP (0.05 micrograms/kg per minute) was infused into the donor kidney artery during transplantation for 46 +/- 2 min, followed by IV administration for 71 +/- 2 min. Our aim was to reduce the incidence of ARF. Nevertheless, ARF occurred immediately after surgery in four of the patients (36%) in this group and, as a result, mannitol was reintroduced. A third group of nine renal graft recipients received alpha-h-ANP (total dose 400 micrograms) as five IV injections within 90 min after transplantation. ARF occurred in four of these patients (44%). We conclude that alpha-h-ANP, administered according to the aforementioned protocols in such small groups of patients, does not seem to be of value in the prevention of ARF after transplantation.

Monitoring of cyclosporin during continuous intravenous administration

Intravenous cyclosporin was administered continuously to 18 consecutive marrow transplant recipients. Blood samples taken from the single lumen central venous line through which the cyclosporin was administered showed invariably high concentrations. Toxic levels were still present after discontinuation of cyclosporin administration for 8 h, while the peripheral blood levels were in the therapeutic range throughout the observation time. These observations may explain some of the reported discrepancies between the levels of cyclosporin and the side-effects when using intravenous cyclosporin. Mean cyclosporin levels remained stable throughout the 4 weeks of continuous intravenous cyclosporin administration, despite a gradual decrease of the mean cyclosporin dose. Dose adaptations were made based on clinical side-effects and cyclosporin concentrations in blood samples from peripheral veins.