Liver disease in kidney transplant recipients

Shifting perspectives in liver diseases after kidney transplantation

Liver diseases after kidney transplantation range from mild biochemical abnormalities to severe hepatitis or cirrhosis. The causes are diverse and mainly associated with hepatotropic viruses, drug toxicity and metabolic disorders. Over the past decade, the aetiology of liver disease in kidney recipients has changed significantly. These relates to the use of direct-acting antiviral agents against hepatitis C virus, the increasing availability of vaccination against hepatitis B and a better understanding of drug-induced hepatotoxicity. In addition, the emergence of the severe acute respiratory syndrome coronavirus 2 pandemic has brought new challenges to kidney recipients. This review aims to provide healthcare professionals with a comprehensive understanding of recent advances in the management of liver complications in kidney recipients and to enable them to make informed decisions regarding the risks and impact of liver disease in this population.

HEPATIC ALTERATIONS IN KIDNEY TRANSPLANT RECIPIENTS FROM THE LARGEST KIDNEY TRANSPLANT CENTER IN BRAZIL

ABSTRACT Background Kidney transplant is the treatment of choice for patients with end-stage renal disease and is associated with lower mortality when compared to dialysis methods. Brazil is the country with the second largest number of kidney transplants in the world and among these patients it has been observed that liver abnormalities are common. The frequency of liver abnormalities ranges from 20-50% post-transplantation, and have an important impact on the survival and quality of life of these patients. There are scarce data about the frequency, causes and characteristics of these alterations. Objective To determine the prevalence of the different causes of hepatic abnormalities in kidney transplant recipients, to associate the characteristics of these abnormalities with demographic, epidemiological and clinical variables, to compare the characteristics of hepatic alterations between different etiologies, and to evaluate possible changes in diagnosis over two different periods of time. Methods Descriptive, cross-sectional observational, epidemiological study was conducted at the outpatient “Hepato-Rim”clinic of Hospital São Paulo (EPM/UNIFESP), a center providing specialized care for patients with hepatic abnormalities and underlying kidney diseases. Results Five-hundred eighty-one transplant patients were evaluated. The most prevalent etiologies of liver abnormalities were hepatitis C and B, iron overload, nonalcoholic fatty liver disease (NAFLD), and drug-induced liver injury (DILI). The most common cause — hepatitis C — was analyzed in greater detail. Compared to the other causes, this infection was more frequent in older patients, female patients, and patients with a longer time since transplantation and hemodialysis. Analysis of the two periods showed that patients of period 1 (P1 — 1993 to 2005) were older and were more frequently referred because of positive serology; referral due to aminotransferases abnormalities predominated during period 2 (P2 — 2006 to 2018). The predominant diagnoses were hepatitis C and B during P1 and NAFLD and DILI during P2. Conclusion Assessment of the main hepatic alterations in kidney transplant recipients is important because it permits better management of these patients in terms of diagnostic investigation and treatment and contributes to the prevention of complications in this special population.

One-Year Outcomes of the Multi-Center StudY to Transplant Hepatitis C-InfeCted kidneys (MYTHIC) Trial

Introduction

Transplanting kidneys from hepatitis C virus (HCV) viremic donors into HCV-negative patients (HCV D-RNA-positive/R-negative) has evolved from experimental to “standard-of-care” at many centers. Nevertheless, most data derive from single centers and provide only short-term follow-up.

Methods

The Multicenter Study to Transplant Hepatitis C-Infected Kidneys (MYTHIC) study was a multicenter (7 sites) trial of HCV D-RNA-positive/R-negative kidney transplantation (KT) followed by 8 weeks of glecaprevir/pibrentasvir (G/P) initiated 2 to 5 days post-KT. Prespecified outcomes included probability of KT (vs. matched waitlist comparators) and 1-year safety outcomes, allograft function, and survival.

Results

Among 63 enrolled patients, 1-year cumulative incidence of KT was approximately 3.5-fold greater for the MYTHIC cohort versus 2055 matched United Network for Organ Sharing (UNOS) comparators who did not opt-in to receive a kidney from an HCV-viremic donor (68% vs. 19%, P < 0.0001). Of 30 HCV D-RNA-positive/R-negative KT recipients, all achieved HCV cure. None developed clinically significant liver disease or HCV-related kidney injury. Furthermore, 1-year survival was 93% and 1-year graft function was excellent (median creatinine 1.17; interquartile range [IQR]: 1.02–1.38 mg/dl). There were 4 cases of cytomegalovirus (CMV) disease among 10 CMV-negative patients transplanted with a kidney from an HCV-viremic/CMV-positive donor.

Conclusion

The 1-year findings from this multicenter trial suggest that opting-in for HCV-viremic KT offers can increase probability of KT with excellent 1-year outcomes. Trial Registration: NCT03781726

Early Hypertransaminasemia after Kidney Transplantation: Significance and Evolution According to Donor Type

Early hypertransaminasemia after kidney transplantation (KT) is frequent. It has been associated with the crosstalk produced between the liver and the kidney in ischemia-reperfusion situations. However, the influence of the donor type has not been evaluated. We present a retrospective study analyzing the increase in serum aspartate aminotransferase/alanine aminotransferase (AST/ALT) during the first three months post-KT in 151 recipients who received thymoglobulin as induction therapy, either from brain-death donors (DBD, n = 75), controlled circulatory death donors (cDCD, n = 33), or uncontrolled DCD (uDCD, n = 43). Eighty-five KT recipients from DBD who received basiliximab were included as controls. From KT recipients who received thymoglobulin, 33.6/43.4% presented with an increase in AST/ALT at 72 h post-KT, respectively. Regarding donor type, the percentage of recipients who experienced 72 h post-KT hypertransaminasemia was higher in uDCD group (65.1/83.7% vs. 20.3/26% in DBD and 20.7/27.6% in cDCD, p < 0.001). Within the control group, 9.4/12.9% of patients presented with AST/ALT elevation. One month after transplant, AST/ALT values returned to baseline in all groups. The multivariate analysis showed that uDCD recipients had 6- to 12-fold higher risk of developing early post-KT hypertransaminasemia. Early post-KT hypertransaminasemia is a frequent and transient event related to the kidney donor type, being more frequent in uDCD recipients.

Liver involvement in kidney disease and vice versa

The liver and kidneys are often similarly affected by a single disease. This is the case in metabolic, immunological, toxic, and infectious diseases, and in the different congenital malformation syndromes. Also, an enzymatic defect in an otherwise healthy liver or the consequences of advanced liver disease by itself can cause kidney disease as a secondary phenomenon. In this review, we describe numerous pathogenic mechanisms leading to dysfunction or malformations of the liver and kidneys in children. We encourage multidisciplinary management for optimal care. A combined liver-kidney transplantation is sometimes needed.