Liver transplantation for Wilson disease

Research progress in stem cell therapy for Wilson disease

Wilson disease (WD), also known as hepatolenticular degeneration, is an autosomal recessive disorder characterized by disorganized copper metabolism caused by mutations in the ATP7B gene. Currently, the main treatment options for WD involve medications such as d-penicillamine, trientine hydrochloride, zinc acetate, and liver transplantation. However, there are challenges that encompass issues of poor compliance, adverse effects, and limited availability of liver sources that persist. Stem cell therapy for WD is currently a promising area of research. Due to the advancement in stem cell directed differentiation technology in vitro and the availability of sufficient stem cell donors, it is expected to be a potential treatment option for the permanent correction of abnormal copper metabolism. This article discusses the research progress of stem cell therapy for WD from various sources, as well as the challenges and future prospects of the clinical application of stem cell therapy for WD.

Structures of the human Wilson disease copper transporter ATP7B

The P-type ATPase ATP7B exports cytosolic copper and plays an essential role in the regulation of cellular copper homeostasis. Mutants of ATP7B cause Wilson disease (WD), an autosomal recessive disorder of copper metabolism. Here, we present cryoelectron microscopy (cryo-EM) structures of human ATP7B in the E1 state in the apo, the putative copper-bound, and the putative cisplatin-bound forms. In ATP7B, the N-terminal sixth metal-binding domain (MBD6) binds at the cytosolic copper entry site of the transmembrane domain (TMD), facilitating the delivery of copper from the MBD6 to the TMD. The sulfur-containing residues in the TMD of ATP7B mark the copper transport pathway. By comparing structures of the E1 state human ATP7B and E2-P_i state frog ATP7B, we propose the ATP-driving copper transport model of ATP7B. These structures not only advance our understanding of the mechanisms of ATP7B-mediated copper export but can also guide the development of therapeutics for the treatment of WD.

Does Liver Transplant Improve Neurological Symptoms in Wilson Disease? Report of 24 Cases

OBJECTIVES

Wilson disease is an inherited disorder that results in copper accumulation in the tissues with liver injury and failure. Orthotopic liver transplant is one of the treatments of choice for this disease. The aim of this study was to compare the neurological symptoms, before and after orthotopic livertransplant, of patients with liver cirrhosis due to Wilson disease, who represent a special group of patients with liver failure.

MATERIALS AND METHODS

Between 2007 and 2020, there were 24 patients with Wilson disease resistant to medical treatment who underwent deceased donor orthotopic livertransplant and were followed up for 1 year, 5 years, and 10 years for evaluation with neurological scoring systems. Patients were also evaluated for postoperative complications and survival.

RESULTS

Of the 24 patients evaluated, there were 13 (54.2%) female patients and 11 (45.8%) male patients, and the mean age was 34 years (range, 14-57 years). One of the patients died from early postoperative sepsis. After orthotopic livertransplant, disease scores returned to normal in 16 patients and improved in the remaining patients. Before transplant, all patients required help in their daily activities. After transplant, there were significant improvements in some symptoms, and the patients became more independent in their daily lives.

CONCLUSIONS

Our study shows that orthotopic liver transplant provides significant improvement in neurological symptoms and quality of life in patients with Wilson disease.

Distinguishing between the complications of Wilson disease-related cirrhosis and HBV-related cirrhosis

OBJECTIVE

Complications affect the outcome of patients with cirrhosis. The favorable prognosis of patients with Wilson disease (WD)-related cirrhosis suggests that its complications differ from those of hepatitis B virus (HBV) infection-related cirrhosis. We aimed to delineate the differences in complications between WD-related and HBV-related cirrhosis.

METHODS

The electronic-medical data from patients with WD-related and HBV-related cirrhosis were extracted and analyzed.

RESULTS

In total, 211 patients with WD-related cirrhosis and 374 patients with HBV-related cirrhosis were enrolled. Most patients with WD progressed to cirrhosis <10 years after disease onset, whereas those with HBV infection often progressed after >10 years. Patients with WD-related cirrhosis had a markedly lower prevalence of ascites (8.5% vs. 38.5%), gastroesophageal varices/variceal bleeding (13.3% vs. 47.6%), renal impairment (0 vs. 7.6%) and primary liver cancer (0 vs. 39.3%; all p < .001) than those with HBV-related cirrhosis. After adjustment for potential confounders, patients with WD-related cirrhosis carried a lower risk of varices/variceal bleeding.

CONCLUSIONS

Although patients with WD progressed to cirrhosis much faster, the prevalence of complications from WD-related cirrhosis was low. Patients with WD-related cirrhosis were less likely to develop gastroesophageal varices/variceal bleeding than those with HBV-related cirrhosis.

Wilson disease and the differential diagnosis of its hepatic manifestations: a narrative review of clinical, laboratory, and liver histological features

Objective

The goal of the present work is to provide an overview of the differential diagnosis of Wilson disease.

Background

Wilson disease is a rare condition due to copper accumulation primarily in the liver and brain. Although there is no definitive cure, current anti-copper treatments are associated with better outcomes if initiated early and if the diagnosis is made promptly. However, diagnostic delays are frequent and often Wilson disease represents a diagnostic challenge. The diagnosis ultimately relies on a combination of clinical, laboratory and genetic findings, and it is crucial that clinicians list Wilson disease in their differential diagnosis, especially in patients presenting with a hepatocellular pattern of liver injury. Some biochemical and liver histological features of Wilson disease overlap with those of more common conditions including nonalcoholic fatty liver disease, alcohol-associated liver disease, and autoimmune hepatitis. In particular, hepatic steatosis, hepatocyte glycogenated nuclei, ballooning degeneration, and Mallory-Denk bodies are often identified in Wilson disease as well as more common liver diseases. In addition, the natural history of liver damage in Wilson disease and the risk of developing liver cancer are largely understudied.

Methods

We conducted an enlarged review of published papers on Wilson disease focusing on its diagnosis and distinctive clinical and liver pathology features in relation to common non-cholestatic liver diseases with the final goal in aiding clinicians in the diagnostic process of this rare but treatable condition.

Conclusions

Aside from markedly altered copper metabolism, Wilson disease has essentially no pathognomonic features that can distinguish it from more common liver diseases. Clinicians should be aware of this challenge and consider Wilson disease in patients presenting with a hepatocellular pattern of liver injury.

Wilson's Disease: An Update on the Diagnostic Workup and Management

Wilson's disease (WD) is a rare autosomal recessive disorder of hepatocellular copper deposition. The diagnostic approach to patients with WD may be challenging and is based on a complex set of clinical findings that derive from patient history, physical examination, as well as laboratory and imaging testing. No single examination can unequivocally confirm or exclude the disease. Timely identification of signs and symptoms using novel biomarkers and modern diagnostic tools may help to reduce treatment delays and improve patient prognosis. The proper way of approaching WD management includes, firstly, early diagnosis and prompt treatment introduction; secondly, careful and lifelong monitoring of patient compliance and strict adherence to the treatment; and, last but not least, screening for adverse effects and evaluation of treatment efficacy. Liver transplantation is performed in about 5% of WD patients who present with acute liver failure at first disease presentation or with signs of decompensation in the course of liver cirrhosis. Increasing awareness of this rare inherited disease among health professionals, emphasizing their training to consider early signs and symptoms of the illness, and strict monitoring are vital strategies for the patient safety and efficacy of WD therapy.

The Need for Consensus About Liver Transplantation For Patients With Neuropsychiatric Wilson's Disease

Liver transplantation is considered an effective therapeutic option for Wilson's disease (WD) patients with hepatic phenotype, since it removes the inherited defects of copper metabolism, and is associated with excellent graft and patient outcomes. The role of liver transplantation in WD patients with mixed hepatic and neuropsychiatric phenotype has remained controversial over time, mainly because of high post-operative complications, reduced survival and a variable, unpredictable rate of neurological improvement. This article critically discusses the recently published data in this field, focussing in more detail on isolated neuropsychiatric phenotype as a potential indication for liver transplantation in WD patients.

Management Perspective of Wilson's Disease: Early Diagnosis and Individualized Therapy

Wilson's disease (WD) is an inherited disease caused by mutations in ATP7B and is characterized by the pathological accumulation of copper in the liver and brain. Common clinical manifestations of WD include a wide range of liver disease and neurological symptoms. In some patients, psychiatric symptoms may be the only manifestation at the time of diagnosis. The clinical features of WD are highly variable and can mimic any disease of internal medicine. Therefore, for unexplained medical diseases, the possibility of WD should not be ignored. Early diagnosis and treatment can improve the prognosis of WD patients and reduce disability and early death. Gene sequencing is becoming a valuable method to diagnose WD, and if possible, all WD patients and their siblings should be genetically sequenced. Copper chelators including D-penicillamine, trientine, and dimercaptosuccinic acid can significantly improve the liver injury and symptoms of WD patients but may have a limited effect on neurological symptoms. Zinc salts may be more appropriate for the treatment of asymptomatic patients or for the maintenance treatment of symptomatic patients. High-quality clinical trials for the drug treatment of WD are still lacking, therefore, individualized treatment options for patients are recommended. Individualized treatment can be determined based on the clinical features of the WD patients, efficacy and adverse effects of the drugs, and the experience of the physician. Liver transplantation is the only effective method to save patients with acute liver failure or with severe liver disease who fail drug treatment.

Liver transplantation in the era of COVID-19

Liver transplantation is considered the ultimate solution for patients with end-stage chronic liver disease or acute liver failure. Patients with liver transplant need special care starting from preoperative preparation, surgical intervention ending with postoperative care. Transplanted patients have to receive immunosuppressive therapy to prevent rejection. Such a state of immune suppression could predispose to different types of infections in liver transplant recipients. Currently, the world is suffering a pandemic caused by a new strain of the coronavirus family called COVID-19. Certain infection control precautions are needed to protect immunocompromised and vulnerable patients, including liver transplant candidates and recipients from acquiring COVID-19 infection. Restricting non-transplant elective surgical procedures, managing transplant patients in separate outpatient clinics, and in-patient wards can prevent transmission of infection both to patients and healthcare workers. Telemedicine can help in the triage of patients to screen for symptoms of COVID-19 before their regular appointment. Management of immunosuppressive therapy and drug-drug interactions in liver transplant recipients infected with COVID-19 should be cautiously practiced to prevent rejection and effectively treat the underlying infection. In this report, we are trying to summarize available evidence about different aspects of the management of liver transplant candidates and recipients in the era of COVID-19.

Outcomes of Liver Transplant for Adults With Wilson's Disease

Wilson's disease (WD) is a rare genetic disorder with protean manifestations. Even if liver transplantation (LT) could represent an effective therapeutic option for patients with end-stage liver disease, it has remained controversial in the presence of neuropsychiatric involvement. This study aimed to examine the frequency of adult LT for WD in Italy, focusing on the disease phenotype at the time of LT. A retrospective, observational, multicenter study was conducted across Italy exploring the frequency and characteristics of adults transplanted for WD between 2006 and 2016. A total of 29 adult WD patients underwent LT during the study period at 11 Italian LT centers (accounting for 0.4% of all LTs performed), and 27 of them were considered in this analysis (male/female, n = 9/18; age at LT, 29 years [19-60 years]; median Model for End-Stage Liver Disease score at LT, 27 [6-49]). Isolated hepatic phenotype was the indication for LT in 17 (63%) patients, whereas 2 (7%) patients underwent LT for neurological impairment on compensated liver disease. Overall 1- and 5-year patient survival was excellent (88% and 83%, respectively). Neuropsychiatric symptoms early after LT completely recovered in only a few patients. In conclusion, WD remains an uncommon, unusual indication for LT in Italy, displaying good post-LT graft and patient survival. Because isolated neuropsychiatric involvement represents a rare indication to LT, more data are needed to properly assess the value of LT for WD in this subset of patients.

[Wilson disease]

Wilson disease is a rare hereditary disorder of copper metabolism. The genetic defect is caused by various mutations in the copper-transporting enzyme ATP7B, located mainly in the liver and brain. Clinical symptoms are highly variable, with any combination of hepatic and/or neurological or psychiatric manifestations. The age of onset varies from early childhood to young adults and can even be manifested in later ages. The clinical diagnosis is based on a combination of clinical, biochemical and molecular markers. Treatment using chelating agents and zinc salts is effective when started early or even better at presymptomatic stages of the disease.

Difficulties in diagnosis and treatment of Wilson disease-a case series of five patients

Wilson disease (WD) may present symptomatically at any age. There is great variability in the neurological symptoms present, in the clinical state of WD patients, and in the response to decoppering therapy. Early diagnosis and compliance with anti-copper therapy are essential. Here we present five different WD cases to illustrate different problems encountered during diagnosis and treatment. The first case demonstrates that decoppering therapy may be very effective even with severe neurological symptoms. In addition, we see the importance of family screening, especially among the proband's siblings. Case 2 shows that we must be very careful during diagnosis. In the reported family, WD was diagnosed in the father of the proband although her brother had liver pathology but not caused by WD. Other cases teach us that decoppering therapy with d-penicillamine must be introduced slowly because of the high risk of neurological deterioration, especially in patients with typical WD brain changes even without neurological signs. We also have to consider concomitant therapies in WD patients. Neuroleptics may cause exacerbation and should be used at a low dose and for the shortest period possible. A full consideration for the issues surrounding the diagnosis and treatment of WD can lead to optimised care with reduced risk of progression and disability.

Wilson disease

Wilson disease (WD) is a potentially treatable, inherited disorder of copper metabolism that is characterized by the pathological accumulation of copper. WD is caused by mutations in ATP7B, which encodes a transmembrane copper-transporting ATPase, leading to impaired copper homeostasis and copper overload in the liver, brain and other organs. The clinical course of WD can vary in the type and severity of symptoms, but progressive liver disease is a common feature. Patients can also present with neurological disorders and psychiatric symptoms. WD is diagnosed using diagnostic algorithms that incorporate clinical symptoms and signs, measures of copper metabolism and DNA analysis of ATP7B. Available treatments include chelation therapy and zinc salts, which reverse copper overload by different mechanisms. Additionally, liver transplantation is indicated in selected cases. New agents, such as tetrathiomolybdate salts, are currently being investigated in clinical trials, and genetic therapies are being tested in animal models. With early diagnosis and treatment, the prognosis is good; however, an important issue is diagnosing patients before the onset of serious symptoms. Advances in screening for WD may therefore bring earlier diagnosis and improvements for patients with WD.

DPM-1001 decreased copper levels and ameliorated deficits in a mouse model of Wilson's disease

In this study, Krishnan et al. present the characterization of DPM-1001 as a potent and highly selective chelator of copper that is orally bioavailable. Treatment of the toxic milk mouse model of Wilson's disease with DPM-1001 lowered the levels of copper in the liver and brain, removing excess copper by excretion in the feces while ameliorating symptoms associated with the disease, suggesting that DPM-1001 should be investigated further as a new therapeutic agent for the treatment of Wilson's disease.

The levels of copper, which is an essential element in living organisms, are under tight homeostatic control. Inactivating mutations in ATP7B, a P-type Cu-ATPase that functions in copper excretion, promote aberrant accumulation of the metal, primarily the in liver and brain. This condition underlies Wilson's disease, a severe autosomal recessive disorder characterized by profound hepatic and neurological deficits. Current treatment regimens rely on the use of broad specificity metal chelators as “decoppering” agents; however, there are side effects that limit their effectiveness. Here, we present the characterization of DPM-1001 {methyl 4-[7-hydroxy-10,13-dimethyl-3-({4-[(pyridin-2-ylmethyl)amino]butyl}amino)hexadecahydro-1H-cyclopenta[a]phenanthren-17-yl] pentanoate} as a potent and highly selective chelator of copper that is orally bioavailable. Treatment of cell models, including fibroblasts derived from Wilson's disease patients, eliminated adverse effects associated with copper accumulation. Furthermore, treatment of the toxic milk mouse model of Wilson's disease with DPM-1001 lowered the levels of copper in the liver and brain, removing excess copper by excretion in the feces while ameliorating symptoms associated with the disease. These data suggest that it may be worthwhile to investigate DPM-1001 further as a new therapeutic agent for the treatment of Wilson's disease, with potential for application in other indications associated with elevated copper, including cancer and neurodegenerative diseases.

Movement Disorders and Neurometabolic Diseases

Many inherited metabolic diseases or inborn errors of metabolism (IEM) cause movement disorders in children. This review focuses on chorea, dystonia, myoclonus, tremor, and parkinsonism. Broad neurometabolic categories commonly responsible for pediatric movement disorders include mitochondrial cytopathies, organic acidemias, mineral metabolism and transport disorders, neurotransmitter diseases, purine metabolism abnormalities, lipid storage conditions, and creatine metabolism dysfunction. Each movement disorder can be caused by many IEM and several of them can cause multiple movement abnormalities. Dietary modifications, medications, and increasingly specific therapy can improve outcomes in children with movement disorders caused by IEM. Recognition and characterization of secondary movement disorders in children facilitate their management and diagnosis, and possible treatment of an underlying IEM.

Advances in Treatment of Wilson Disease

Background

Wilson disease (WD) is an inherited neurometabolic disorder that results in excessive copper deposition in the liver and the brain, affecting children and young adults. Without treatment the disease is invariably fatal. Though treatments for WD have been available since the 1950s, the disease continues to be associated with considerable morbidity and mortality because of missed diagnosis, and delayed or inadequate treatment. In this paper we survey WD-related literature in order to review recent advances in WD treatment.

Methods

We performed a literature search using the PubMed database for articles relating to WD and its medical treatment. We reviewed the articles, and cross-references of relevant articles, to summarize the current practices for treatment of WD.

Results

The survey shows that if WD is properly treated, in most patients the liver can be stabilized, even severe neurological disability reversed, and patients can resume normal lives.

Discussion

Medical treatment for WD includes use of copper chelators (penicillamine, trientine, dimercaprol, dimercaptopropane sulfonate, and ammonium tetrathiomolybdate) and drugs that decrease gastrointestinal copper absorption. Our knowledge of the treatment approaches has benefited from the large systematic clinical studies that have been conducted over the last decade. For each drug used to treat WD, we surveyed its development, indication for use, dosing, efficacy, and adverse effects.