Predicting Tacrolimus Concentrations in the Skin of Adult Kidney Transplant Recipients: A Feasibility Study.

Solid organ transplant recipients are at an increased risk of developing skin cancers due to chronic immunosuppression, particularly with calcineurin inhibitors. Tacrolimus is the most prescribed calcineurin inhibitor in this patient cohort, and understanding tacrolimus concentrations in the skin will facilitate the development of anti-cancer preventive and therapeutic strategies. Here, we show that in mice, tacrolimus blood levels peaked rapidly ∼1 h post last oral dose while skin levels rose more slowly and remained high for at least 6 h. Subsequently, tacrolimus skin and blood concentrations were assessed in 15 kidney transplant recipients. The mean age was 61 years, the average time post-transplant was 7 years (range 0-21 years) and 87% were male. The average skin sampling time post tacrolimus dosing was 6 h 32 min. Skin tacrolimus concentrations ranged from 7.1 ng/g to 71.2 ng/g and correlated with blood concentrations (r = 0.6). Mouse and human mean skin concentrations were in a similar range. Our data suggests that tacrolimus measurements in the blood may be used to approximate tacrolimus concentrations in the skin of kidney transplant recipients, and further exploited for the delivery of anti-cancer therapies designed to antagonize the immunosuppressive effects of tacrolimus in the skin.

Critically important outcomes for infection in trials in kidney transplantation: An international survey of patients, caregivers, and health professionals.

BACKGROUND: Infections are a common complication following kidney transplantation, but are reported inconsistently in clinical trials. This study aimed to identify the infection outcomes of highest priority for patients/caregivers and health professionals to inform a core outcome set to be reported in all kidney transplant clinical trials. METHODS: In an international online survey, participants rated the absolute importance of 16 infections and eight severity dimensions on 9-point Likert Scales, with 7-9 being critically important. Relative importance was determined using a best-worst scale. Means and proportions of the Likert-scale ratings and best-worst preference scores were calculated. RESULTS: 353 healthcare professionals (19 who identified as both patients/caregiver and healthcare professionals) and 220 patients/caregivers (190 patients, 22 caregivers, eight who identified as both) from 55 countries completed the survey. Both healthcare professionals and patients/caregivers rated bloodstream (mean 8.4 and 8.5, respectively; aggregate 8.5), kidney/bladder (mean 7.9 and 8.4; aggregate 8.1), and BK virus (mean 8.1 and 8.6; aggregate 8.3) as the top three most critically important infection outcomes, whilst infectious death (mean 8.8 and 8.6; aggregate 8.7), impaired graft function (mean 8.4 and 8.7; aggregate 8.5) and admission to the intensive care unit (mean 8.2 and 8.3; aggregate 8.2) were the top three severity dimensions. Relative importance (best-worst) scores were consistent. CONCLUSIONS: Healthcare professionals and patients/caregivers consistently identified bloodstream infection, kidney/bladder infections, and BK virus as the three most important infection outcomes, and infectious death, admission to intensive care unit and infection impairing graft function as the three most important infection severity outcomes.

Survey study of trends in adult nephrology advanced training in Australia and New Zealand.

BACKGROUND: There has been considerable growth in nephrology advanced trainee numbers in Australia and New Zealand, with uncertain effects on clinical experience, competence and employment outcomes. AIMS: To review the perceived adequacy and temporal trends of advanced training in nephrology in Australia and New Zealand by evaluating training experiences, personal views on important aspects of training and nephrology, career paths and early employment outcomes. METHODS: An online survey was distributed to members of the Australian and New Zealand Society of Nephrology through email in December 2020. Responses were sought from current trainees and from nephrologists qualifying since 2014. Likert scale proportions were calculated and group comparisons made using the Chi-squared test. RESULTS: A total of 88 participants returned the survey yielding a response rate of 32%, with a representative sample of trainees and consultants from across Australia and New Zealand. Training was reported as adequate in most aspects of clinical nephrology, although 88% of respondents felt poorly prepared for entering private practice and 61% reported inadequate training in kidney histopathology. Exposure to clinical procedures was variable, with adequate training in percutaneous kidney biopsy, but mostly inadequate training in dialysis access insertion. Sixty-nine percent of nephrologists completed their advanced training entirely in large urban centres and 85% worked in an urban area after training. Only 23% of consultants were engaged in full-time clinical employment in their first-year post-training and 78% were undertaking at least one of dual specialty training or a higher degree by research. Demand for subspecialty fellowships was high. CONCLUSION: Trainees and nephrologists in Australia and New Zealand are currently satisfied with their training in most aspects of nephrology; however, some clinical experiences are perceived as inadequate and early career paths after advanced training are increasingly diverse.

Dialysis modality utilization patterns and mortality in older persons initiating dialysis in Australia and New Zealand.

AIM: The benefits of dialysis in the older population remain highly debated, particularly for certain dialysis modalities. This study aimed to explore the dialysis modality utilization patterns between in-centre haemodialysis (ICHD), peritoneal dialysis (PD) and home haemodialysis (HHD) and their association with outcomes in older persons. METHODS: Older persons (≥75 years) initiating dialysis in Australia and New Zealand from 1999 to 2018 reported to the Australia and New Zealand Dialysis and Transplant (ANZDATA) registry were included. The main aim of the study was to characterize dialysis modality utilization patterns and describe individual characteristics of each pattern. Relationships between identified patterns and survival, causes of death and withdrawal were examined as secondary analyses, where the pattern was considered as the exposure. RESULTS: A total of 10 306 older persons initiated dialysis over the study period. Of these, 6776 (66%) and 1535 (15%) were exclusively treated by ICHD and PD, respectively, while 136 (1%) ever received HHD during their dialysis treatment course. The remainder received both ICHD and PD: 906 (9%) started dialysis on ICHD and 953 (9%) on PD. Different individual characteristics were seen across dialysis modality utilization patterns. Median survival time was 3.0 (95%CI 2.9-3.1) years. Differences in survival were seen across groups and varied depending on the time period following dialysis initiation. Dialysis withdrawal was an important cause of death and varied according to individual characteristics and utilization patterns. CONCLUSION: This study showed that dialysis modality utilization patterns in older persons are associated with mortality, independent of individual characteristics.

Prebiotic Supplementation in Kidney Transplant Recipients for Preventing Infections and Gastrointestinal Upset: A Randomized Controlled Feasibility Study.

OBJECTIVES: Modulating the large intestinal microbiome of kidney transplant recipients (KTRs) may reduce infectious complications. The aim of this study is to assess the feasibility of a randomized controlled trial of prebiotics in reducing infections and gastrointestinal symptoms in KTRs. (DESIGN) AND METHODS: Acute KTRs were recruited to a double-blind, placebo-controlled, randomized trial at a single kidney transplant center. Patients were provided with prebiotics or placebo for 7 weeks. The primary outcome was feasibility, defined as recruitment of ≥80% of eligible people within 6 months. Secondary outcomes included adherence and tolerability, participant retention in trial, proportions of participants providing serum and stool specimens, self-reported quality of life, gastrointestinal symptoms, and infection events. RESULTS: During the 7-week period, 72 patients met eligibility criteria, of whom 60 (83%) consented to participate (mean ± standard deviation age 53 ± 12 years; 62% males). Fifty-six (78%) participants were randomized (27 interventions and 29 controls). Although participants receiving intervention experienced reduced gastrointestinal symptoms (-0.28 [interquartile range, IQR -0.67 to 0.08] vs. -0.07 [IQR -0.27 to 0], P = .03), both control and intervention groups were similar in adherence (67% vs. 72%, P = .36), tolerability (56% vs. 62%, P = .64), quality of life (-0.2 [IQR -0.6 to 0] vs. -0.2 [IQR -0.8 to 0], P = .82), and infection events (33% vs. 34%, P = .83). Blood and stool samples were collected from ≥90% of participants in both groups. CONCLUSIONS: It is feasible to recruit and retain acute KTRs in a randomized, placebo-controlled trial examining the effect of prebiotics on infections and gastrointestinal symptoms. This study also showed that prebiotics significantly reduced gastrointestinal symptoms.

Characteristics of the gastrointestinal microbiota in paired live kidney donors and recipients.

BACKGROUND: There are few studies that have examined whether dysbiosis occurs in kidney donors and transplant recipients following kidney transplant surgery. AIM: To ascertain whether changes occur in the gastrointestinal microbiota of the kidney donor and recipient following kidney transplantation. METHODS: Kidney transplant recipients and their donors were prospectively enrolled in a pilot study to collect one faecal sample prior to, and another faecal sample between four to eight weeks following surgery. Gastrointestinal microbiota richness, Shannon diversity measures and functional assessments of kidney donors and recipients were analysed via metagenomic sequencing. RESULTS: The study included 12 donors (median age 56 years, 6 females) and 12 recipients (median age 51 years, 3 females). Donor microbiota showed no significant changes in gastrointestinal microbiota richness, Shannon diversity, or functional assessments before and after nephrectomy. Recipient microbiota was altered post-transplant, reflected in reductions of the mean (±SD) richness values (156 ± 46.5 to 116 ± 38.6, p = 0.002), and Shannon diversity (3.57 ± 0.49 to 3.14 ± 0.52, p = 0.007), and a dramatic increase in Roseburia spp. abundance post-transplant (26-fold increase from 0.16 ± 0.0091 to 4.6 ± 0.3; p = 0.006; FDR = 0.12). Functionally, the post-transplant microbial community shifted towards those taxa using the glycolysis pathway (1.2-fold increase; p = 0.02; FDR = 0.26) for energy metabolism, while those functions involved with reactive oxygen species degradation decreased (2.6-fold; p = 0.006; FDR = 0.14). CONCLUSION: Live donor kidney transplantation and standard care post-transplant result in significant alterations in gut microbiota richness, diversity, composition and functional parameters in kidney transplant recipients but not in their kidney donors.

Dialysis initiation in older persons across centres and over time in Australia and New Zealand.

AIM: With improved life expectancy over time, the burden of kidney failure resulting in kidney replacement therapy (KRT) in older persons is increasing. This study aimed to describe the age distribution at dialysis initiation in Australia and New Zealand (ANZ) across centres and over time. METHODS: Adults initiating dialysis as first KRT in ANZ from 1999 to 2018 reported to the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry were included. The primary outcomes were the age distribution and the proportion of older persons (75 years and older) initiating dialysis across centres and over time. Secondary outcomes were characterization of the older population compared with younger people and differences in dialysis modality and treatment trajectories between groups. RESULTS: Over the study period, 55 382 people initiated dialysis as first KRT, including 10 306 older persons, in 100 centres. Wide variation in age distribution across states/countries was noted, although the proportion of older persons at dialysis initiation did not significantly change over time (from 13% in 1999 to 19% in 2003, then remaining stable thereafter). Older persons were less likely to be treated with home therapies compared with younger people. Older persons were mostly Caucasians; had higher socioeconomic position, more cardiovascular comorbidities and higher eGFR at baseline; and resided in major cities. Higher proportions of older persons per centre were noted in privately funded facilities. CONCLUSION: Wide variations were noted in the proportions of older persons initiating dialysis across centres and states/country, which were associated with different case-mix across regions, particularly in terms of ethnicity, remoteness and socioeconomic advantage.

Variability and trends over time and across centres in haemodialysis weekly duration in Australia and New Zealand.

AIM: Haemodialysis treatment prescription varies widely internationally. This study explored patient- and centre-level characteristics associated with weekly haemodialysis hours. METHODS: Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry data were analysed. Characteristics associated with weekly duration were evaluated using mixed-effects linear regression models with patient- and centre-level covariates as fixed effects, and dialysis centre and state as random effects using the 2017 prevalent in-centre haemodialysis (ICHD) and home haemodialysis (HHD) cohorts. Evaluation of patterns of weekly duration over time analysed the 2000 to 2017 incident ICHD and HHD cohorts. RESULTS: Overall, 12 494 ICHD and 1493 HHD prevalent patients in 2017 were included. Median weekly treatment duration was 13.5 (interquartile range [IQR] 12-15) hours for ICHD and 16 (IQR 15-20) hours for HHD. Male sex, younger age, higher body mass index, arteriovenous fistula/graft use, Aboriginal and Torres Strait Islander ethnicity and longer dialysis vintage were associated with longer weekly duration for both ICHD and HHD. No centre characteristics were associated with duration. Variability in duration across centres was very limited in ICHD compared with HHD, with variation in HHD being associated with state. Duration did not vary significantly over time for ICHD, whereas longer weekly HHD treatments were reported between 2006 and 2012 compared with before and after this period. CONCLUSION: This study in the Australian and New Zealand haemodialysis population showed that weekly duration was primarily associated with patient characteristics. No centre effect was demonstrated. Practice patterns seemed to differ across states/countries, with more variability in HHD than ICHD.

Patient and center characteristics associated with kidney transplant outcomes: a binational registry analysis.

This registry-based study evaluated the contribution of center characteristics to kidney transplant outcomes in adult first kidney transplant recipients in Australia and New Zealand between 2004 and 2014. Primary outcomes were mortality and graft failure, and secondary outcomes were transplant complications. Overall, 6970 transplants from 17 centers were included. For deceased donor transplants, 5-year patient and graft survival rates varied considerably (81.0-93.9% and 72.2-88.3%, respectively). Variations in mortality and graft failure were partially reduced after adjustment for patient characteristics (1% and 20% reductions) and more markedly reduced after adjustment for center characteristics (41% and 55% reductions). For living donor transplants, 5-year patient and graft survival rates varied (89.7-100% and 79.2-96.9%, respectively). Centers with high average total ischemic times (>14 h) were associated with higher mortality for both deceased (adjusted hazard ratio [(AHR] 2.24, 95% CI 1.21-4.13) and living donor transplants (AHR 1.76, 95% CI 1.02-3.04). Small center size (<35 new kidney transplants/year) was associated with a lower hazard of mortality for living donor kidney transplants (AHR 0.48, 95% CI 0.28-0.81). No center characteristic was associated with graft failure. The appreciable variations in deceased donor kidney transplant recipient and graft survival outcomes across centers were attributable to center effects.

Perioperative antibiotics for preventing post-surgical site infections in solid organ transplant recipients.

BACKGROUND: Solid organ transplant recipients are at high risk for infections due to the complexity of surgical procedures combined with the impact of immunosuppression. No consensus exists on the role of antibiotics for surgical site infections in solid organ transplant recipients. OBJECTIVES: To assess the benefits and harms of prophylactic antimicrobial agents for preventing surgical site infections in solid organ transplant recipients. SEARCH METHODS: The Cochrane Kidney and Transplant Register of Studies was searched up to 21 April 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov. SELECTION CRITERIA: All randomised controlled trials (RCTs) and quasi-RCTs in any language assessing prophylactic antibiotics in preventing surgical site infections in solid organ transplant recipients at any time point after transplantation. DATA COLLECTION AND ANALYSIS: Two authors independently determined study eligibility, assessed quality, and extracted data. Primary outcomes were surgical site infections and antimicrobial resistance. Other outcomes included urinary tract infections, pneumonias and septicaemia, death (any cause), graft loss, graft rejection, graft function, adverse reactions to antimicrobial agents, and outcomes identified by the Standardised Outcomes of Nephrology Group (SONG), specifically graft health, cardiovascular disease, cancer and life participation. Summary effect estimates were obtained using a random-effects model and results were expressed as risk ratios (RR) and 95% confidence intervals (CI). The quality of the evidence was assessed using the risk of bias and the GRADE approach. MAIN RESULTS: We identified eight eligible studies (718 randomised participants). Overall, five studies (248 randomised participants) compared antibiotics versus no antibiotics, and three studies (470 randomised participants) compared extended duration versus short duration antibiotics. Risk of bias was assessed as high for performance bias (eight studies), detection bias (eight studies) and attrition bias (two studies). It is uncertain whether antibiotics reduce the incidence of surgical site infections as the certainty of the evidence has been assessed as very low (RR 0.42, 95% CI 0.21 to 0.85; 5 studies, 226 participants; I2 = 25%). The certainty of the evidence was very low for all other reported outcomes (death, graft loss, and other infections). It is uncertain whether extended duration antibiotics reduces the incidence of surgical site infections in either solid organ transplant recipients (RR 1.19, 95% CI 0.58 to 2.48; 2 studies, 302 participants; I2 = 0%) or kidney-only transplant recipients (RR 0.50, 95% CI 0.05 to 5.48; 1 study, 205 participants) as the certainty of the evidence has been assessed as very low. The certainty of the evidence was very low for all other reported outcomes (death, graft loss, and other infections). None of the eight included studies evaluated antimicrobial agent adverse reactions, graft health, cardiovascular disease, cancer, life participation, biochemical and haematological parameters, intervention cost, hospitalisation length, or overall hospitalisation costs. AUTHORS' CONCLUSIONS: Due to methodological limitations, risk of bias and significant heterogeneity, the current evidence for the use of prophylactic perioperative antibiotics in transplantation is of very low quality. Further high quality, adequately powered RCTs would help better inform clinical practice.

Transplant associated infections-The role of the gastrointestinal microbiota and potential therapeutic options.

Infectious complications are common following kidney transplantation and rank in the top five causes of death in patients with allograft function. Over the last 5 years, there has been emerging evidence that changes in the gastrointestinal microbiota following kidney transplantation may play a key role in the pathogenesis of transplant-associated infections. Different factors have emerged which may disrupt the interaction between the gastrointestinal microbiota and the immune system, which may lead to infective complications in kidney transplant recipients. Over the last 5 years, there has been emerging evidence that changes in the gastrointestinal microbiota following kidney transplantation may play a key role in the pathogenesis of transplant-associated infections. This review will discuss the structure and function of the gastrointestinal microbiota, the changes that occur in the gastrointestinal microbiota following kidney transplantation and the factors underpinning these changes, how these changes may lead to transplant-associated infectious complications and potential treatments which may be instituted to mitigate this risk.

Infectious Complications Following Kidney Transplantation-A Focus on Hepatitis C Infection, Cytomegalovirus Infection and Novel Developments in the Gut Microbiota.

The incidence of infectious complications, compared with the general population and the pre-transplant status of the recipient, increases substantially following kidney transplantation, causing significant morbidity and mortality. The potent immunosuppressive therapy given to prevent graft rejection in kidney transplant recipients results in an increased susceptibility to a wide range of opportunistic infections including bacterial, viral and fungal infections. Over the last five years, several advances have occurred that may have changed the burden of infectious complications in kidney transplant recipients. Due to the availability of direct-acting antivirals to manage donor-derived hepatitis C infection, this has opened the way for donors with hepatitis C infection to be considered in the donation process. In addition, there have been the development of medications targeting the growing burden of resistant cytomegalovirus, as well as the discovery of the potentially important role of the gastrointestinal microbiota in the pathogenesis of post-transplant infection. In this narrative review, we will discuss these three advances and their potential implications for clinical practice.

A scoring system to screen elderly potential kidney transplant recipients: a simple tool for a complex task.

Despite the rapid growth in the number of dialysis patients ⩾65, relatively few of these patients are receiving transplants. Dusseux et al. present a simple scoring system that helps to identify a group of such patients with a higher survival rate on dialysis. They suggest that such a screening tool might help to identify older patients for more comprehensive transplant assessment.

End-Stage Kidney Disease Due to Fibrillary Glomerulonephritis and Immunotactoid Glomerulopathy - Outcomes in 66 Consecutive ANZDATA Registry Cases.

BACKGROUND: Fibrillary glomerulonephritis (FGN) and immunotactoid glomerulopathy (IG) are uncommon and characterised by non-amyloid fibrillary glomerular deposits. The aim of this study was to investigate characteristics and outcomes of patients undergoing renal replacement therapy (RRT) for end-stage kidney disease (ESKD) secondary to FGN and IG. METHODS: All ESKD patients who commenced RRT in Australia and New Zealand 1 January 1990 to 31 December 2010 were included. Outcomes were assessed by Kaplan-Meier, multivariate logistic-regression analysis and multivariable Cox proportional-hazards survival analysis. RESULTS: Of 45,216 individuals with ESKD, 55 (0.12%) had FGN and 11 (0.02%) had IG. The median survival of FGN patients on dialysis (5.63 years, 95% CI 3.31-7.96) was not significantly different from patients with other ESKD causes (median 4.01 years, 95% CI 4.34-4.47; log-rank 1.32, p = 0.25), but was significantly longer than that of IG patients (median 2.93 years, 95% CI 0.00-6.17; log-rank 4.8, p = 0.03). Thirteen (24%) FGN patients received 13 renal-allografts, 4 (36%) IG patients received 4 renal-allografts and 11,528 (26%) other ESKD patients received 12,278 renal-allografts. FGN patients experienced comparable outcomes to other ESKD patients for both 10-year patient survival (100 vs. 84%, p = 0.93) and renal-allograft survival (67 vs. 76%, p = 0.06). For IG, the median follow-up was 3.66 years with 75% patient survival and 100% renal-allograft survival. One (8%) FGN patient and 1 (25%) IG patient experienced recurrent FGN and IG respectively in their allograft. CONCLUSION: Patients with FGN have comparable dialysis and renal transplant outcomes to patients with other causes of ESKD. IG patients have inferior survival on dialysis, although renal transplant outcomes are acceptable. Disease recurrence in renal-allografts was low for both FGN and IG.

Cessation of immunosuppression during chemotherapy for post-transplant lymphoproliferative disorders in renal transplant patients.

BACKGROUND: The optimal reduction of immunosuppressive therapy (IST) in renal transplant patients with post-transplant lymphoproliferative disorders (PTLDs) is uncertain. As chemotherapy is immunosuppressive, IST may be stopped during this time without compromising graft function. Subsequent long-term reduction of IST reduces relapse risk, but may increase risk of graft rejection. METHODS: We performed a retrospective, matched cohort study of adult renal transplant patients in whom IST was ceased during chemotherapy and resumed at lower dose (calcineurin inhibitor at 50%, prednisolone ≤10 mg daily, no third agent) approximately 6 weeks after chemotherapy. Outcomes were compared with those of renal transplant patients without PTLD, matched for creatinine at equivalent time post-transplant that PTLD was diagnosed in cases, as well as for age, gender and year of transplant. RESULTS: Twenty-four cases of PTLD occurring at a median of 9.2 years post-transplant were compared with 83 matched controls. PTLD cases were followed for a median of 11.9 years. Using competing risks analysis, time to 25% increase in serum creatinine was not significantly different between the two groups [adjusted hazard ratio (HR) 1.8, 95% confidence interval (CI) 0.89-3.6]. Similar results were obtained using multivariable Cox regression analysis (HR 1.19, 95% CI 0.44-3.23). Only one PTLD case experienced a ≥25% increase in creatinine <6 months after IST cessation in the setting of progressive PTLD and death. Three cases recommenced dialysis, compared with three controls (HR 2.5, 95% CI 0.47-13.00). Five-year patient survival rates for cases and controls were 70 and 94%, respectively (P = 0.01). CONCLUSIONS: IST can be safely ceased during chemotherapy for PTLD in renal transplant patients. Furthermore, long-term reduction in IST is not associated with a significant difference in renal function deterioration. Prospective trials are needed to address the optimal reduction of IST in PTLDs.

Biological variation of high sensitivity cardiac troponin-T in stable dialysis patients: implications for clinical practice.

BACKGROUND: Changes in high sensitivity cardiac troponin-T (hs-cTnT) concentrations may reflect either acute myocardial injury or biological variation. Distinguishing between these entities is essential to accurate diagnosis, however, the biological variation of hs-cTnT in dialysis population is currently unknown. We sought to estimate the within- and between-person coefficients of variation of hs-cTnT in stable dialysis patients, and derive the critical difference between measurements needed to exclude biological variation with 99% confidence. METHODS: Fifty-five prevalent haemo- and peritoneal-dialysis patients attending two metropolitan hospitals were assessed on 10 consecutive occasions; weekly for 5 weeks then monthly for 4 months. Assessments were conducted at the same dialysis cycle time-point and entailed hs-cTnT testing, clinical review, electrocardiography, and bioimpedance spectroscopy. Patients were excluded if they developed clinical or physiological instability. RESULTS: In total 137 weekly and 114 monthly hs-cTnT measurements from 42 stable patients were analysed. Respective between- and within-person coefficients of variation were 83% and 7.9% for weekly measurements, and 79% and 12.6% for monthly measurements. Within-person variation was unaffected by dialysis modality or cardiac co-morbidity. The bidirectional 99% reference change value was -25% and +33% for weekly measurements, and -37% and +58% for monthly measurements. CONCLUSIONS: The between-person variation of hs-cTnT in the dialysis population is markedly greater than within-person variation indicating that hs-cTnT testing is best applied in this population using a relative change strategy. An increase of 33% or a reduction of 25% in serial hs-cTnT concentrations measured at weekly intervals excludes change due to analytical and biological variation alone with 99% confidence.

End-stage kidney disease due to Alport syndrome: outcomes in 296 consecutive Australia and New Zealand Dialysis and Transplant Registry cases.

BACKGROUND: Alport syndrome is a rare inheritable renal disease. Clinical outcomes for patients progressing to end-stage kidney disease (ESKD) are not well described. METHODS: This study aimed to investigate the characteristics and clinical outcomes of patients from Australia and New Zealand commencing renal replacement therapy (RRT) for ESKD due to Alport syndrome between 1965 and 1995 (early cohort) and between 1996 and 2010 (contemporary cohort) compared with propensity score-matched, RRT-treated, non-Alport ESKD controls. RESULTS: A total of 58 422 patients started RRT during this period of which 296 (0.5%) patients had Alport ESKD. In the early cohort, Alport ESKD was associated with superior dialysis patient survival [adjusted hazard ratio (HR): 0.41, 95% confidence interval (CI): 0.20-0.83, P = 0.01], renal allograft survival (HR: 0.74, 95% CI: 0.54-1.01, P = 0.05) and renal transplant patient survival (HR: 0.43, 95% CI: 0.28-0.66, P < 0.001) compared with controls. In the contemporary cohort, no differences were observed between the two groups for dialysis patient survival (HR: 1.42, 95% CI: 0.65-3.11, P = 0.38), renal allograft survival (HR: 1.01, 95% CI: 0.57-1.79, P = 0.98) or renal transplant patient survival (HR: 0.67, 95% CI: 0.26-1.73, P = 0.41). One Alport patient (0.4%) had post-transplant anti-glomerular basement membrane (anti-GBM) disease. Four female and 41 male Alport patients became parents on RRT with generally good neonatal outcomes. CONCLUSION: Alport syndrome patients experienced comparable dialysis and renal transplant outcomes to matched non-Alport ESKD controls in the contemporary cohort due to relatively greater improvements in outcomes for non-Alport ESKD patients over time. Post-transplant anti-GBM disease was rare.

The association between tacrolimus exposure and tremor, headache and insomnia in adult kidney transplant recipients: A systematic review.

PURPOSE: Tremor, headache and insomnia have been linked to the immunosuppressant, tacrolimus. The aim of this systematic review was to determine if there is a correlation between tacrolimus exposure and new-onset tremor, headache and insomnia experienced by adult kidney transplant recipients. METHODS: PubMed, Embase, Cochrane Library and CINAHL databases were searched up to 11 April 2023 for published studies which reported on tacrolimus exposure in adult kidney transplant recipients, alongside information on treatment-emergent neurologic manifestations, including tremor, headache and insomnia. Review articles, case studies, conference abstracts and articles not published in English in peer-reviewed journals were excluded. The Physiotherapy Evidence Database and Newcastle-Ottawa Quality Assessment Scales were used to assess risk of bias. Extracted data was analysed via a narrative synthesis. RESULTS: Eighteen studies involving 4030 patients in total were included in the final analysis. These comprised five randomised control trials and thirteen observational studies. Studies failed to find significant association between tacrolimus trough concentrations in whole blood and the incidence of neurologic side effects such as tremor, headache and insomnia; however, in one study the incidence of toxicity requiring a dose reduction increased with increasing, supratherapeutic targeted levels. Females, especially Black females, and older age were positively associated with the prevalence of neurologic adverse effects. Results were conflicting regarding whether extended-release formulations were associated with fewer neurologic complications than immediate-release formulations. CONCLUSION: The varied study designs and criteria for reporting tremor, headache and insomnia impacted on the quality of the data for exploring the relationship between tacrolimus exposure and the onset of neurologic manifestations experienced after kidney transplantation. Studies that examine defined neurologic complications as the primary outcome, and that consider novel markers of tacrolimus exposure while assessing the potential contribution of multiple covariate factors, are required.

Does Age Influence Immunosuppressant Drug Pharmacokinetics in Kidney Transplant Recipients?

BACKGROUND: The pharmacokinetics of immunosuppressant drugs may change with advancing age, potentially affecting patient outcomes. OBJECTIVE: To characterise the effects of age on the pharmacokinetic and exposure parameters of tacrolimus, mycophenolate, and prednisolone. METHODS: Pharmacokinetic profiling, involving whole blood tacrolimus, total and free plasma mycophenolic acid (MPA), total plasma mycophenolic acid glucuronide (MPAG), and total and free plasma prednisolone, was performed in an older and younger adult cohort. Thirteen samples were drawn on a single occasion, pre-oral dose and then at 0.25, 0.5, 0.75, 1, 1.25, 1.5, 2, 3, 4, 6, 9, and 12 h post-dose. Non-compartmental analysis was conducted using the PKNCA package, and pharmacokinetic and exposure parameters were compared between age groups using a Mann-Whitney test. A regression analysis was conducted for free MPA and MPAG using significant variables of interest. RESULTS: This exploratory study included 21 older and 18 younger adults. Dose-adjusted tacrolimus, total MPA and free prednisolone pharmacokinetic parameters were not different between age groups; however, for free MPA and MPAG, older recipients had significantly greater minimum and maximum concentrations, trough concentrations, and half-life. There was a two-fold increase in free MPA exposure in older adults (median dose-adjusted AUC0-12: 1284 vs. 684 µg h/L, p < 0.0001); MPAG exposure similarly increased. Age was significantly associated with free MPA and MPAG exposure, and free MPA exposure was associated with haematocrit (p < 0.05). CONCLUSION: Differences in MPA were found with advancing age and may be due to altered kidney function, haematocrit, plasma protein binding and/or drug absorption. Future research should explore specific covariate contributions to this further.