High Calcineurin Inhibitor Intrapatient Variability Is Associated With Renal Allograft Inflammation, Chronicity, and Graft Loss

Assessing health literacy in transplant patients to better tailor the content of their therapeutic education: an observational study

OBJECTIVES

Evaluate health literacy in transplant patients to better tailor the content of their continuing therapeutic education.

METHODS

A 20-item questionnaire divided into five themes (sport/recreation, dietary measures, hygiene measures, recognition of the signs of graft rejection and medication management) was sent to transplant patient associations. Participants' responses (a score out of 20 points), were analysed according to demographic characteristics, transplanted organ (kidney, liver or heart), type of donor (living or deceased), participation in a therapeutic patient education (TPE) programme, management of end-stage renal disease (with or without dialysis) and the date of transplant.

RESULTS

327 individuals completed the questionnaires (mean age 63.3±12.7 years, mean time post-transplant 13.1±12.1 years). From 2 years after transplantation, the patients' score decreases significantly compared with the score obtained at hospital discharge. Patients who received TPE had significantly higher scores than patients who did not receive it, but only in the first 2 years post-transplant. The scores were different depending on the organs transplanted. Patients' knowledge varied according to the theme; the percentage of errors being higher for questions related to hygienic and dietary rules.

CONCLUSION

These findings highlight the importance of the role of the clinical pharmacist in maintaining the transplant recipient's health literacy level over time to increase graft life. We show the topics on which pharmacists must acquire solid knowledge to best meet the needs of transplant patients.

Long-term Kidney Transplant Survival Across the Globe

BACKGROUND

The outcomes after kidney transplantation (KT), including access, wait time, and other issues around the globe, have been studied. However, issues do vary from one country to another.

METHODS

We obtained data from several countries from North America, South America, Europe, Asia, and Australia, including the number of patients awaiting KT from 2015, transplant rate per million population (pmp), proportion of living donor and deceased donor (LD/DD) KT, and posttransplant survival. We also sought opinions on key difficulties faced by each of these countries with respect to KT and long-term survival.

RESULTS

Variation in access to KT across the globe was noted. Countries with the highest rates of KT pmp included the United States (79%) and Spain (71%). A higher proportion of LD transplants was noted in Japan (93%), India (85%), Singapore (63%), and South Korea (63%). A higher proportion of DD KTs was noted in Spain (90%), Brazil (90%), France (85%), Italy (85%), Finland (85%), Australia-New Zealand (80%), and the United States (77%). The 5-y graft survival for LD was highest in South Korea (95%), Singapore (94%), Italy (93%), Finland (93%), and Japan (93%), whereas for DD, it was South Korea (93%), Italy (88%), Japan (86%), and Singapore (86%). The common issues surrounding KTs are access and a limited number of LDs and DDs. Key issues identified for long-term survival were increasing age of donors and recipients, higher recipient comorbidity, and posttransplant events, such as alloimmune injury to the kidney, infection, cancer, and suboptimal adherence to therapy.

CONCLUSIONS

A unified approach is necessary to improve issues surrounding KT as the demand continues to increase.

Predicting outcomes after kidney transplantation: Can Pareto's rules help us to do so?

Kidney transplantation is the best option for kidney replacement therapy, even considering that most of the times the grafts do not survive as long as their recipients. In the Khalil et al's experience, published in this issue of the Journal, they analyze their second kidney graft survival and describe those significant predictors of early loss. This editorial comments on the results and put in perspec tive that most of the times, long-term graft survival could be inadvertently jeopardized if the immunosuppressive therapy is reduced or withdrawn for any reason, and that it could happen frequently if the transplant physician intends to innovate with the clinical care without proper evidence-based data.

Implementing a self-reported immunosuppression adherence questionnaire to screen for non-adherence in routine care of kidney transplant recipients

INTRODUCTION

Self-reported measures of immunosuppression adherence have been largely examined in research settings.

METHODS

In this single center study of 610 kidney transplant recipients, we examined if a voluntary, non-anonymous self-report measure could identify non-adherence in a routine clinic setting and how patients perceived such a measure. Non-adherence was measured using the Basel Assessment of Adherence to Immunosuppressive Medications Scale (BAASIS) and patient perception was elicited using a customized questionnaire.

RESULTS

Non-responders to the survey (15%) were younger, more likely to be black, and less likely to have had a pre-emptive transplant. Among complete responders (n = 485), 38% reported non-adherence with non-adherent patients being younger (54 y vs. 60 y; p = .01), less likely to have been on dialysis pre-transplant (59% vs. 68%; p = .04), further out from transplant (37 vs. 22 months; p < .001) and had more rejections in the preceding year (8% vs. 3%; p = .02). Self-reported non-adherence was associated with higher calcineurin inhibitor intra-patient variability (27.4% vs. 24.5%; p = .02), but not with donor-specific antibody detection (27.8% vs. 21.2%, p = .15). Of patients providing feedback (n = 500), the majority of patients felt comfortable reporting adherence (92%), that the survey was relevant to their visit (71%), and that the survey did not interfere with their clinic visit (88%).

CONCLUSION

In summary, a self-reported questionnaire during clinic visits identified immunosuppression non-adherence in a significant proportion of patients and was well received by patients. Integrating self-report measures into routine post-transplant care may enable early identification of non-adherence.

Impact of Resolved Preformed, Persistent Preformed, and De Novo Anti-HLA Donor-Specific Antibodies in Kidney Transplant Recipients on Long-Term Renal Graft Outcomes

The post-transplant evolution of antihuman leukocyte antigen donor-specific antibodies (anti-HLA DSAs) includes three clinical patterns: resolved preformed DSAs, persistent preformed DSAs, and de novo DSAs. The aim of this retrospective study was to analyze the impact of resolved preformed, persistent preformed, and de novo anti-HLA-A, -B, and -DR DSAs in kidney transplant recipients on long-term renal allograft outcomes. This is a post hoc analysis of the study conducted in our transplant center. One hundred eight kidney transplant recipients were included in the study. Patients were followed for a minimum of 24 months after allograft biopsy, which was performed 3 to 24 months after kidney transplantation. The identification of persistent preformed DSAs at the time of biopsy was the most significant predictor of the combined endpoint of the study (>30% decline in estimated glomerular filtration rate or death-censored graft loss; HR = 5.96, 95% CI 2.041-17.431, p = 0.0011), followed by the occurrence of de novo DSAs (HR = 4.48, 95% CI 1.483-13.520, p = 0.0079). No increased risk was observed in patients with resolved preformed DSAs (HR = 1.10, 95% CI 0.139-8.676, p = 0.9305). Patients with resolved preformed DSAs have similar graft prognoses as patients without DSAs, therefore, the persistence of preformed DSAs and development of de novo DSAs are associated with inferior long-term allograft outcomes.

Torque Teno Virus Load Predicts Opportunistic Infections after Kidney Transplantation but Is Not Associated with Maintenance Immunosuppression Exposure

Measuring the non-pathogenic Torque Teno Virus (TTV) load allows assessing the net immunosuppressive state after kidney transplantation (KTx). Currently, it is not known how exposure to maintenance immunosuppression affects TTV load. We hypothesized that TTV load is associated with the exposure to mycophenolic acid (MPA) and tacrolimus. We performed a prospective study including 54 consecutive KTx. Blood TTV load was measured by an in-house PCR at months 1 and 3. Together with doses and trough blood levels of tacrolimus and MPA, we calculated the coefficient of variability (CV), time in therapeutic range (TTR) and concentration/dose ratio (C/D) of tacrolimus, and the MPA-area under the curve (AUC-MPA) at the third month. TTV load at the first and third month discriminated those patients at risk of developing opportunistic infections between months 1 and 3 (AUC-ROC 0.723, 95%CI 0.559-0.905, p = 0.023) and between months 3 and 6 (AUC-ROC 0.778, 95%CI 0.599-0.957, p = 0.028), respectively, but not those at risk of acute rejection. TTV load did not relate to mean tacrolimus blood level, CV, TTR, C/D and AUC-MPA. To conclude, although TTV is a useful marker of net immunosuppressive status after KTx, it is not related to exposure to maintenance immunosuppression.

Association of Circulating Anti-HLA Donor-Specific Antibodies and Their Characteristics, including C1q-Binding Capacity, in Kidney Transplant Recipients with Long-Term Renal Graft Outcomes

Post-transplant antihuman leukocyte antigen donor-specific antibodies (anti-HLA DSAs) monitoring in kidney transplant recipients remains unclear and is currently under investigation. The pathogenicity of anti-HLA DSAs is determined by antibody classes, specificity, mean fluorescent intensity (MFI), C1q-binding capacity, and IgG subclasses. The aim of this study was to investigate the association of circulating DSAs and their characteristics with renal allograft long-term outcomes. The study included 108 consecutive patients from our transplant center who underwent kidney allograft biopsy between November 2018 and November 2020, 3 to 24 months after kidney transplantation. At the time of biopsy, patients' sera were collected for analysis of anti-HLA DSAs. Patients were followed for a median time of 39.0 months (Q1-Q3, 29.8-45.0). Detection of anti-HLA DSAs at the time of biopsy (HR = 5.133, 95% CI 2.150-12.253, p = 0.0002) and their C1q-binding capacity (HR = 14.639, 95% CI 5.320-40.283, p ≤ 0.0001) were independent predictors of the composite of sustained 30% reduction from estimated glomerular filtration rate or death-censored graft failure. Identification of anti-HLA DSAs and their C1q-binding capacity could be useful in identifying kidney transplant recipients at risk for inferior renal allograft function and graft failure. Analysis of C1q is noninvasive, accessible, and should be considered in clinical practice in post-transplant monitoring.

Seeking Standardized Definitions for HLA-incompatible Kidney Transplants: A Systematic Review

BACKGROUND

There is no standard definition for "HLA incompatible" transplants. For the first time, we systematically assessed how HLA incompatibility was defined in contemporary peer-reviewed publications and its prognostic implication to transplant outcomes.

METHODS

We combined 2 independent searches of MEDLINE, EMBASE, and the Cochrane Library from 2015 to 2019. Content-expert reviewers screened for original research on outcomes of HLA-incompatible transplants (defined as allele or molecular mismatch and solid-phase or cell-based assays). We ascertained the completeness of reporting on a predefined set of variables assessing HLA incompatibility, therapies, and outcomes. Given significant heterogeneity, we conducted narrative synthesis and assessed risk of bias in studies examining the association between death-censored graft failure and HLA incompatibility.

RESULTS

Of 6656 screened articles, 163 evaluated transplant outcomes by HLA incompatibility. Most articles reported on cytotoxic/flow T-cell crossmatches (n = 98). Molecular genotypes were reported for selected loci at the allele-group level. Sixteen articles reported on epitope compatibility. Pretransplant donor-specific HLA antibodies were often considered (n = 143); yet there was heterogeneity in sample handling, assay procedure, and incomplete reporting on donor-specific HLA antibodies assignment. Induction (n = 129) and maintenance immunosuppression (n = 140) were frequently mentioned but less so rejection treatment (n = 72) and desensitization (n = 70). Studies assessing death-censored graft failure risk by HLA incompatibility were vulnerable to bias in the participant, predictor, and analysis domains.

CONCLUSIONS

Optimization of transplant outcomes and personalized care depends on accurate HLA compatibility assessment. Reporting on a standard set of variables will help assess generalizability of research, allow knowledge synthesis, and facilitate international collaboration in clinical trials.

Clinical recommendations for posttransplant assessment of anti-HLA (Human Leukocyte Antigen) donor-specific antibodies: A Sensitization in Transplantation: Assessment of Risk consensus document

Although anti-HLA (Human Leukocyte Antigen) donor-specific antibodies (DSAs) are commonly measured in clinical practice and their relationship with transplant outcome is well established, clinical recommendations for anti-HLA antibody assessment are sparse. Supported by a careful and critical review of the current literature performed by the Sensitization in Transplantation: Assessment of Risk 2022 working group, this consensus report provides clinical practice recommendations in kidney, heart, lung, and liver transplantation based on expert assessment of quality and strength of evidence. The recommendations address 3 major clinical problems in transplantation and include guidance regarding posttransplant DSA assessment and application to diagnostics, prognostics, and therapeutics: (1) the clinical implications of positive posttransplant DSA detection according to DSA status (ie, preformed or de novo), (2) the relevance of posttransplant DSA assessment for precision diagnosis of antibody-mediated rejection and for treatment management, and (3) the relevance of posttransplant DSA for allograft prognosis and risk stratification. This consensus report also highlights gaps in current knowledge and provides directions for clinical investigations and trials in the future that will further refine the clinical utility of posttransplant DSA assessment, leading to improved transplant management and patient care.

The Clinical Impact of Anti-HLA Donor Specific Antibody Detection Through First Year Screening on Stable Kidney Transplant Recipients

Anti-HLA Donor Specific Antibody (DSA) detection post kidney transplant has been associated with adverse outcomes, though the impact of early DSA screening on stable patients remain unclear. We analyzed impact of DSA detection through screening in 1st year stable patients (n = 736) on subsequent estimated glomerular filtration rate (eGFR), death censored graft survival (DCGS), and graft failure (graft loss including return to dialysis or re-transplant, patient death, or eGFR < 20 ml/min at last follow up). Patients were grouped using 1st year screening into DSA+ (Class I, II; n = 131) or DSA- (n = 605). DSA+ group were more DR mismatched (p = 0.02), more sensitized (cPRA ≥90%, p = 0.002), less Caucasian (p = 0.04), and had less pre-emptive (p = 0.04) and more deceased donor transplants (p = 0.03). DSA+ patients had similar eGFR (54.8 vs. 53.8 ml/min/1.73 m², p = 0.56), DCGS (91% vs. 94%, p = 0.30), and graft failure free survival (76% vs. 82%, p = 0.11). DSA timing and type did not impact survival. Among those with a protocol biopsy (n = 515), DSA detected on 1st year screening was a predictor for graft failure on multivariate analysis (1.91, 95% CI 1.03-3.55, p = 0.04). Overall, early DSA detection in stable patients was an independent risk factor for graft failure, though only among those who underwent a protocol biopsy.

Bimonthly viral monitoring for late-onset cytomegalovirus infection in kidney transplant recipients

Kidney transplant recipients with high-risk cytomegalovirus (CMV) serostatus (seropositive donor to seronegative recipient) are at risk for late-onset CMV after cessation of antiviral prophylaxis. We report findings from a strategy of bimonthly (every 2 weeks) CMV screening for late-onset CMV. This is a single-center retrospective cohort study of 70 high-risk CMV kidney transplant recipients transplanted between June 2016 and September 2018. Patients were monitored at 6-12 months post-transplantation for late-onset CMV using bimonthly CMV nucleic acid testing (NAT). Adherence to screening and its correlation with CMV-related hospitalizations were assessed. Failure to prevent CMV-related hospitalization was classified into three categories (non-adherence to CMV testing, rapid CMV progression, and health system failure). Twenty-one (30%) patients developed CMV DNAemia, of whom 10 (14%) required hospitalization. Reasons for CMV-related hospitalization despite screening were (i) screening non-adherence (50%), (ii) rapid progression (40%), and (iii) health system failure (10%). Adherence to screening was associated with lower viral counts at diagnosis (r = -.44, p = .049) and a trend towards lower risk of CMV-related hospitalization (OR: 0.97 per 1% increase in adherence; 95% CI: 0.94-1.00; p = .06). Bimonthly monitoring for late-onset CMV allows for early CMV detection and may lower CMV-related hospitalization.

Tacrolimus intrapatient variability in solid organ transplantation: A multiorgan perspective

BACKGROUND

Tacrolimus therapy in solid organ transplant (SOT) recipients is challenging due to its narrow therapeutic window and pharmacokinetic variability both between patients and within a single patient. Intrapatient variability (IPV) of tacrolimus trough concentrations has become a novel marker of interest for predicting transplant outcomes. The purpose of this review is to evaluate the association of tacrolimus IPV with graft and patient outcomes and identify interventions to improve IPV in SOT recipients.

METHODS

A systematic review of the literature was performed using PubMed and Embase from database inception to September 20, 2020. Studies were eligible only if they evaluated an association between tacrolimus IPV and transplant outcomes. Both pediatric and adult studies were included. Measures of variability were limited to standard deviation, coefficient of variation, and time in therapeutic range.

RESULTS

Forty-four studies met the inclusion criteria. Studies were published between 2008 and 2020 and were observational in nature. Majority of data were published in adult kidney transplant recipients and identified an association with rejection, de novo donor specific antibody (dnDSA) formation, graft loss, and patient survival. Evaluation of IPV-directed interventions was limited to small preliminary studies.

CONCLUSIONS

High tacrolimus IPV has been associated with poor outcomes including acute rejection, dnDSA formation, graft loss, and patient mortality in SOT recipients. Future research should prospectively explore IPV-directed interventions to improve transplant outcomes.