Frequency of hyperuricemia and effect of calcineurin inhibitors on serum uric acid levels in liver transplanted children

Sodium-glucose cotransporter 2 inhibitors and cardiorenal outcomes in kidney transplantation

PURPOSE OF REVIEW

This review aims to explore the current evidence regarding cardiovascular and kidney outcomes in patients who undergo treatment with sodium-glucose cotransporter 2 inhibitors (SGLT2i) post kidney transplantation.

RECENT FINDINGS

Summary findings from individual studies included in this review showed largely favorable results in the kidney transplant recipients (KTRs) being treated with SGLT2i.These outcomes included parameters such as allograft function, glycemic control, proteinuria, blood pressure, weight loss and safety profile, among others. Almost all the studies reported an initial 'dip' in eGFR, followed by recovery, after the initiation of SGLT2i treatment. None of the studies reported significant interaction of SGLT2i with immunosuppressive medications. The most common adverse effects noted in these studies were infection-related including UTI and genital mycosis. None of the studies reported acute graft rejection attributable to SGLT2i therapy.

SUMMARY

SGLT2i can play a significant role in improving health outcomes in KTRs. However, clinical trials with larger representation of KTRs longer follow-up period are needed to draw more substantial conclusions.

Immunosuppressive Agents-Effects on the Cardiovascular System and Selected Metabolic Aspects: A Review

The widespread use of immunosuppressive drugs makes it possible to reduce inflammation in autoimmune diseases, as well as prevent transplant rejection in organ recipients. Despite their key action in blocking the body's immune response, these drugs have many side effects. These actions primarily affect the cardiovascular system, and the incidence of complications in patients using immunosuppressive drugs is significant, being associated with a higher incidence of cardiovascular incidents such as myocardial infarction and stroke. This paper analyzes the mechanisms of action of commonly used immunosuppressive drugs and their impact on the cardiovascular system. The adverse effect of immunosuppressive drugs is associated with toxicity within the cardiovascular system, which may be a problem in the clinical management of patients after transplantation. Immunosuppressants act on the cardiovascular system in a variety of ways, including fibrosis and myocardial remodeling, endothelium disfunction, hypertension, atherosclerosis, dyslipidemia or hyperglycaemia, metabolic syndrome, and hyperuricemia. The use of multidrug protocols makes it possible to develop regimens that can reduce the incidence of cardiovascular events. A better understanding of their mechanism of action and the range of complications could enable physicians to select the appropriate therapy for a given patient, as well as to reduce complications and prolong life.

A Prediction Model for Tacrolimus Daily Dose in Kidney Transplant Recipients With Machine Learning and Deep Learning Techniques

Tacrolimus is a major immunosuppressor against post-transplant rejection in kidney transplant recipients. However, the narrow therapeutic index of tacrolimus and considerable variability among individuals are challenges for therapeutic outcomes. The aim of this study was to compare different machine learning and deep learning algorithms and establish individualized dose prediction models by using the best performing algorithm. Therefore, among the 10 commonly used algorithms we compared, the TabNet algorithm outperformed other algorithms with the highest R² (0.824), the lowest prediction error [mean absolute error (MAE) 0.468, mean square error (MSE) 0.558, and root mean square error (RMSE) 0.745], and good performance of overestimated (5.29%) or underestimated dose percentage (8.52%). In the final prediction model, the last tacrolimus daily dose, the last tacrolimus therapeutic drug monitoring value, time after transplantation, hematocrit, serum creatinine, aspartate aminotransferase, weight, CYP3A5, body mass index, and uric acid were the most influential variables on tacrolimus daily dose. Our study provides a reference for the application of deep learning technique in tacrolimus dose estimation, and the TabNet model with desirable predictive performance is expected to be expanded and applied in future clinical practice.

Expert consensus on management of metabolic disease in Chinese liver transplant recipients

Metabolic disease, including diabetes mellitus, hypertension, dyslipidemia, obesity, and hyperuricemia, is a common complication after liver transplantation and a risk factor for cardiovascular disease and death. The development of metabolic disease is closely related to the side effects of immunosuppressants. Therefore, optimization of the immunosuppressive regimen is very important for the prevention and treatment of metabolic disease. The Chinese Society of Organ Transplantation has developed an expert consensus on the management of metabolic diseases in Chinese liver transplant recipients based on recent studies. Emphasis is placed on the risk factors of metabolic diseases, the effect of immunosuppressants on metabolic disease, and the prevention and treatment of metabolic diseases.

Prevalence of renal dysfunction in tacrolimus-treated pediatric transplant recipients: a systematic review

Renal dysfunction after non-renal transplantation in adult tacrolimus-treated transplant patients is well documented. Little is known about its prevalence in children. Age-related changes in both disposition and effect of tacrolimus as well as renal function may preclude extrapolation of adult data to children. To systematically review the literature on renal dysfunction in non-renal pediatric transplant recipients treated with tacrolimus. PubMed/Medline, Embase, and Google were searched from their inception until April 19, 2012, with the search terms "tacrolimus," "renal function," "transplantation," and "children." Eighteen of 385 retrieved papers were considered relevant. Twelve dealt with liver, four with heart transplant, one with heart and lung transplant, and one with intestinal recipients. Reported prevalences of mild and severe chronic kidney disease ranged from 0% to 39% and 0% to 71.4%, respectively, for liver, and from 22.7% to 40% and 6.8% to 46%, respectively, for heart and/or lung transplant recipients. Ranges remained wide after adjusting for follow-up time and disease severity. Possible explanations are inclusion bias and definitions used for renal dysfunction. A considerable proportion of pediatric non-renal transplant patients who receive tacrolimus-based immunosuppression, appear to suffer from chronic kidney disease. This conclusion warrants further research into the real risk, its risk factors, and individualization of immunosuppressant therapy.

Hyperuricemia beyond 1 year after kidney transplantation in pediatric patients: Prevalence and risk factors

Hyperuricemia is frequent among adult renal transplant recipients; however, data among pediatric kidney recipients are scarce. This study is designed to estimate the prevalence and risk factors of late post-transplant hyperuricemia in pediatric recipients. A retrospective observational multicenter study on 179 pediatric renal recipients (5–18 years) was conducted between April 2008 and January 2011 from five kidney transplant centers of Tehran, Iran. All recipients were followed up for more than 1 year (5.9 ±3.3 years) after transplantation. A total of 17686 blood samples were obtained for serum uric acid (SUA). The normal range of SUA was defined as SUA 1.86–5.93 mg/dl for children between 2 and 15 years in both genders; 2.40–5.70 mg/dl for girls aged >15 years; 3.40–7.0 mg/dl for boys aged >15 and more than 6 and 7 mg/dl in boys and girls older than 15 years old. The median age of the children was 13 years. Male recipients were more popular than female (male/female 59/41%). Hyperuricemia was detected in 50.2% of patients. Mean SUA concentration was 5.9±1.7 mg/dl and mean SUA concentration in hyperuricemic patients was 7.7±1.2 mg/dl. While at multivariate logistic regression elevated serum creatinine concentration (P<0.001) and the time span after renal transplantation (P=0.02) had impact on late post-transplant hyperuricemia. High cyclosporine level (C0 and C2) was not risk factor for huperuricemia. Late post-transplant hyperuricemia was found in about half of pediatric renal recipients, and was associated with impaired renal allograft function.

Liver transplantation in Greek children: 15 years experience

Liver transplantation (LT) is the only available live-saving procedure for children with irreversible liver failure. This paper reports our experience from the follow-up of 16 Greek children with end-stage liver failure who underwent a LT. Over a period of 15 years, 16 pediatric liver recipients received follow up after being subjected to OLT (orthotopic liver transplantation) due to end-stage liver failure. Nine children initially presented with extrahepatic biliary atresia, 2 with acute liver failure after toxic mushroom ingestion, 2 with intrahepatic cholestasis, 2 with metabolic diseases and one with hepatoblastoma. Ten children received a liver transplant in the Organ Transplantation Unit of Aristotle University of Thessaloniki and the rest in other transplant centers. Three transplants came from a living-related donor and 13 from a deceased donor. Six children underwent immunosuppressive treatment with cyclosporine, mycophenolate mofetil and corticosteroids, and 7 with tacrolimus, mycophenolate mofetil and corticosteroids. Three out of 16 children died within the first month after the transplantation due to post-transplant complications. Three children presented with acute rejection and one with chronic organ rejection which was successfully managed. Five children presented with cytomegalovirus infection, 5 with Epstein-Barr virus, 2 with HSV(1,2), 2 with ParvoB19 virus, 2 with varicella-zoster virus and one with C. Albicans infection. One child presented with upper gastrointestinal hemorrhage and one with small biliary paucity. A satisfying outcome was achieved in most cases, with good graft function, except for the patient with small biliary paucity who required re-transplantation.The long-term clinical course of liver transplanted children is good under the condition that they are attended in specialized centers.

Risk factors for cyclosporin A nephrotoxicity in children with steroid-dependant nephrotic syndrome

BACKGROUND AND OBJECTIVES

Cyclosporin A (CsA) is a well-established treatment for steroid-dependent nephrotic syndrome (SDNS) that may, however, cause chronic ischemic renal lesions. The objective of the study was to assess the prevalence of CsA nephrotoxicity (CsAN) in protocol biopsies of children with SDNS.

DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS

From 1990 through 2008, we performed 71 renal biopsies in 53 patients with SDNS. The mean CsA C2 levels were 466 +/- 134 ng/ml, and the mean duration of treatment was 4.7 +/- 2.0 yr before biopsy (range 2.9 to 12.7 yr).

RESULTS

CsAN was observed in 22 (31%) of 71 renal biopsies. Of these, 11 corresponded to isolated vascular or tubular lesions, and 11 corresponded to combined vascular and tubular lesions. The majority of CsAN lesions were mild (17 of 22). In no cases were lesions graded as severe. By regression analysis, CsAN was positively associated with the use of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) and with hyperuricemia and negatively associated with minimal-change lesions. By multivariate analysis, only association with the use of ACEIs or ARBs retained significance. Stratification of the population according to CsA C2 levels showed increased risk for CsAN for C2 levels >600 ng/ml.

CONCLUSIONS

Mild to moderate CsAN occurs in approximately one third of patients who have SDNS and are treated with CsA for >3 yr. Our data suggest that patients who require high dosages of CsA or treatment for hypertension, in particular when ACEIs/ARBs are used, are at higher risk for CsAN.

Hyperuricemia after liver transplantation in children

Uric acid may be involved in the development and progression of kidney diseases. Hyperuricemia is a common feature in adult liver transplant recipients but there is limited information in children. In order to estimate the incidence, predictors of hyperuricemia in pediatric liver transplant recipients, and to assess whether hyperuricemia may impact long-term renal function determined by measured GFR, we reviewed data of 70 children who received a first liver transplant between 1991 and 2005 (median follow-up 7.1 yr). Renal function tests performed annually included uric acid concentration, inulin and uric acid clearances. The cumulative incidence of hyperuricemia was 32% at 10-yr post-transplantation, mainly because of decreased urate excretion. The only factor significantly associated with an increased risk of hyperuricemia was older age. After adjustment for donor and recipient age, gender, primary liver disease, immunosuppression, and post-operative acute renal failure, hyperuricemia as time dependent variable tended to predict (p = 0.05) subsequent CRI. The control of serum urate concentration in eight of the 21 hyperuricemic patients either by nutritional management or by allopurinol was not followed by a significant GFR improvement. Hyperuricemia after liver transplantation in children is a frequent problem which needs further investigation.

Calcineurin inhibitor sparing in paediatric solid organ transplantation : managing the efficacy/toxicity conundrum

Despite their efficacy, the calcineurin inhibitors (CNIs) ciclosporin and tacrolimus carry a risk of debilitating adverse effects, especially nephrotoxicity, that affect the long-term outcome and survival of children who are given organ transplants. Simple reduction in dosage of CNI has little or no long-term benefit on their adverse effects, and complete withdrawal without threatening graft outcome may only be possible after liver transplantation. Until the last decade, the only option was to increase corticosteroid and/or azathioprine doses, which imposed additional long-term hazards. Considered here are the emerging generation of new agents offering an opportunity for improving long-term graft survival, minimizing CNI-related adverse events and ensuring patient well-being.A holistic, multifaceted strategy may need to be considered - initial selection and optimized use and monitoring of immunosuppressant regimens, early recognition of indicators of patient and graft dysfunction, and, where applicable, early introduction of CNI-sparing regimens facilitating CNI withdrawal. The evidence reviewed here supports these approaches but remains far from definitive in paediatric solid organ transplantation. Because de novo immunosuppression uses CNI in more than 93% of patients, reduction of CNI-related adverse effects has focused on CNI sparing or withdrawal.A recurring theme where sirolimus and mycophenolate mofetil have been used for this purpose is the importance of their early introduction to limit CNI damage and provide long-term benefit: for example, long-term renal function critically reflects that at 1 year post-transplant. While mycophenolic acid shows advantages over sirolimus in preserving renal function because the latter is associated with proteinuria, sirolimus appears the more potent immunosuppressant but also impairs early wound healing. The use of CNI-free immunosuppressant regimens with depleting or non-depleting antibodies plus sirolimus and mycophenolic acid needs much wider investigation to achieve acceptable rejection rates and conserve renal function. The adverse effects of the alternative immunosuppressants, particularly the dyslipidaemia associated with sirolimus, needs to be minimized to avoid replacing one set of adverse effects (from CNIs) with another. While we can only conjecture that judicious combinations with the second generation of novel immunosuppressants currently in development will provide these solutions, a rationale of low-dose therapy with multiple immunosuppressants acting by complementary mechanisms seems to hold the promise for efficacy with minimal toxicity until the vision of tolerance achieves reality.