Diagnosis and management of Wilson's disease: results of a single center experience

Relapse following withdrawal of D-penicillamine from combination (D-penicillamine + zinc) therapy in hepatic Wilson disease

OBJECTIVES

Long-term D-penicillamine (D-pen) therapy in Wilson disease (WD) has numerous adverse effects which advocates its withdrawal, but with an inherent risk of relapse. This prospective observational study was conducted with the objective of evaluating incidence of relapse following withdrawal of D-pen from combination (D-pen + zinc) therapy in maintenance phase of previously symptomatic hepatic WD.

METHODS

Hepatic WD patients <18 years of age and on combination therapy for >2 years with 6 months of biochemical remission were included. Biochemical remission was defined as achievement of (i) aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤1.5 times upper limit of normal (ULN), (ii) serum albumin >3.5 g/dL, international normalized ratio (INR) <1.5 and (iii) 24-h urinary copper excretion (UCE) <500 mcg/day, nonceruloplasmin-bound-copper (NCC) <15 mcg/dL. After D-pen withdrawal, monthly liver function test (LFT) and INR and 3 monthly UCE and NCC were done till 1 year or relapse (elevation of AST/ALT/both >2 times ULN or total bilirubin >2 mg/dL), whichever occurred earlier.

RESULTS

Forty-five patients enrolled with median combination therapy duration of 36 months. Sixty percent of them had their index presentation as decompensated cirrhosis. Fourteen patients (31.8%) relapsed (cumulative incidence: 4 at 3 months, 11 at 6 months, and 14 at 12 months after D-pen discontinuation). All relapsers had index presentation as decompensated cirrhosis. On Cox-regression, ALT at D-pen withdrawal was an independent predictor of relapse (hazard ratio [HR]: 1.077, 95% confidence interval [CI]: 1.014-1.145, p = 0.017) with area under the receiver operating characteristic (AUROC) of 0.860. ALT ≥40 U/L predicted risk of relapse with 85.7% sensitivity, 70.9% specificity.

CONCLUSION

Incidence of relapse after withdrawal of D-pen from combination therapy is 31.8% in hepatic WD. ALT ≥40 U/L, at the time of D-pen stoppage, predicts future relapse.

Clinical profile of adult and pediatric patients with hepatic Wilson's disease

BACKGROUND

The clinical profile varies in patients with Wilson's disease (WD). There is paucity of data regarding adult and pediatric patients with hepatic WD.

METHODS

As many as 140 consecutive patients diagnosed with hepatic WD between December 2006 and January 2021 were included in the study. Data was collected regarding the demographic parameters, clinical presentation, extrahepatic organ involvement, liver histology and laboratory investigations. Adult and children (0-14 years) with hepatic WD were compared regarding these features.

RESULT

Eighty-eight adults and 52 children were included in the study. The median age of presentation was 17 years (range: 1.1-42 years). Male preponderance was seen (adult 68/88, 69%; children 40/52, 77%). Adults as compared to children presented more commonly as cirrhosis (52/88 vs. 15/52, p = 0.0005) and with hepatic decompensation (35/88 vs. 9/52, p = 0.005). Presentation with acute-on-chronic liver failure (ACLF) was more common in children (10/52 vs. 2/88, p = 0.0005). Twenty-eight-day mortality was 50% (5/10) in children and none in adults presenting with ACLF. Nazer's Prognostic Index (≥ 7) and New Wilson Index were more accurate in predicting mortality among children with ACLF with AUROC 1, while AARC (APASL ACLF Research Consortium) was less accurate with AUROC 0.45. Liver histology findings were similar in adults and children. Extrahepatic involvement was also similar. (8/88 in adults vs. 3/52 children, p value 0.48).

CONCLUSION

Most patients with WD present as cirrhosis in adulthood. ACLF is more common in children. Nazer's prognostic index and new Wilson Index score are accurate in predicting mortality in children with ACLF.

An Unusual Presentation of Wilson's Disease

Wilson's disease affects the metabolism of copper and is a rare hereditary disorder that is inherited autosomally recessively. The liver and brain are the main organs affected by this disorder, which causes progressive hepatolenticular degeneration. A 15-year-old male patient arrived at the outpatient department (OPD) with mild abdominal pain on the right side, and both eyes showed Kayser-Fleischer (KF) rings. An abdominal ultrasound showed that the spleen was enlarged. Copper levels in urine were found to be higher. After a liver biopsy, cirrhosis, and mild chronic active hepatitis were found. The majority of hematological indicators were normal; however, a peripheral blood smear revealed mild thrombocytopenia. Wilson's disease is uncommon, so diagnosing it requires a high degree of suspicion. In circumstances of inexplicable liver cirrhosis or isolated neurological symptoms, it could go unnoticed. The only primary complaint in the case being presented was abdominal pain. However, the age upon presentation, the existence of KF rings in both eyes, and other tests helped us get the diagnosis.

Challenges and dilemmas in pediatric hepatic Wilson's disease

Wilson disease is an autosomal recessive disorder affecting the ATP7B gene located on chromosome 13q. This leads to copper deposition in various organs, most importantly in the liver and brain. The genetic mutations are vast, well reported in the West but poorly documented in developing countries. Hence the diagnosis is made with a constellation of clinico-laboratory parameters which have significant overlap with other liver diseases and often pose a significant dilemma for clinicians. Diagnostic scoring systems are not fool-proof. The availability and affordability of chelators in developing countries impact the drug compliance of patients. While D-penicillamine is a potent drug, its side effects lead to drug discontinuation. Trientine is cost-prohibitive in developing countries. There is no single test to assess the adequacy of chelation. Exchangeable urinary copper is an essential upcoming diagnostic and prognostic tool. In the presence of cirrhosis, hypersplenism clouds the assessment of myelosuppression of drugs. Similarly, it may be difficult to distinguish disease tubulopathy from drug-induced glomerulonephritis. Neurological worsening due to chelators may appear similar to disease progression. Presentation as fulminant hepatic failure requires rapid workup. There is a limited window of opportunity to salvage these patients with the help of plasmapheresis and other liver-assisted devices. This review addresses the challenges and clinical dilemmas faced at beside in developing countries.

Evaluation and Management of Nutritional Consequences of Chronic Liver Diseases

Liver diseases are the major predisposing conditions for the development of malnutrition, sarcopenia, and frailty. Recently, the mechanism of the onset of these complications has been better established. Regardless of the etiology of the underlying liver disease, the clinical manifestations are common. The main consequences are impaired dietary intake, altered macro- and micronutrient metabolism, energy metabolism disturbances, an increase in energy expenditure, nutrient malabsorption, sarcopenia, frailty, and osteopathy. These complications have direct effects on clinical outcomes, survival, and quality of life. The nutritional status should be assessed systematically and periodically during follow-up in these patients. Maintaining and preserving an adequate nutritional status is crucial and should be a mainstay of treatment. Although general nutritional interventions have been established, special considerations are needed in specific settings such as decompensated cirrhosis, alcohol-related liver disease, and metabolic-dysfunction-associated fatty liver disease. In this review, we summarize the physiopathology and factors that impact the nutritional status of liver disease. We review how to assess malnutrition and sarcopenia and how to prevent and manage these complications in this setting.

Evaluation of vitamin B6 supplementation in Wilson's disease patients treated with D-penicillamine

INTRODUCTION

Wilson's disease (WD) is a copper metabolism disorder characterised by a progressive accumulation of this metal mainly in the liver and the brain. Treatment is based on the removal of copper operated by the chelators, among which, D-penicillamine (DP) is prescribed as a first-line treatment in most situations. There is some evidence in linking the use of DP with a risk of vitamin B6; therefore, vitamin supplementation is sometimes recommended, although non-consensually. The objective of our study was to evaluate the level of vitamin B6 in WD patients treated with DP with and without associated supplementation.

METHODOLOGY

All WD patients followed at the National Reference Centre for WD in Lyon between January 2019 and December 2020 treated with DP for more than 1 year were included and separated in two groups according to vitamin B6 supplementation. The level of vitamin B6 was measured by the determination of pyridoxal phosphate (PLP).

RESULTS

A total of 37 patients were included. Average age of 23.3±14.8 years, 15 patients with <18 years. Median duration of treatment was 51 (55.8) months. 15 patients were under vitamin B6 supplementation and 22 had interrupted it for more than 1 year. The median PLP level was significantly higher in the group with supplementation, 137.2 (86.7) nmol/L vs 64.9 (30.8) nmol/(p<0.01). No patient had a PLP level<35 nmol/L.

CONCLUSION

Long-term stable WD patients under DP treatment probably do not need vitamin B6 supplementation.

Stimulation of Liver Fibrosis by N2 Neutrophils in Wilson's Disease

BACKGROUND & AIMS

Wilson's disease is an inherited hepatoneurologic disorder caused by mutations in the copper transporter ATP7B. Liver disease from Wilson's disease is one leading cause of cirrhosis in adolescents. Current copper chelators and zinc salt treatments improve hepatic presentations but frequently worsen neurologic symptoms. In this study, we showed the function and machinery of neutrophil heterogeneity using a zebrafish/murine/cellular model of Wilson's disease.

METHODS

We investigated the neutrophil response in atp7b-/- zebrafish by live imaging, movement tracking, and transcriptional analysis in sorted cells. Experiments were conducted to validate liver neutrophil heterogeneity in Atp7b-/- mice. In vitro experiments were performed in ATP7B-knockout human hepatocellular carcinomas G2 cells and isolated bone marrow neutrophils to reveal the mechanism of neutrophil heterogeneity.

RESULTS

Recruitment of neutrophils into the liver is observed in atp7b-/- zebrafish. Pharmacologic stimulation of neutrophils aggravates liver and behavior defects in atp7b-/- zebrafish. Transcriptional analysis in sorted liver neutrophils from atp7b-/- zebrafish reveals a distinct transcriptional profile characteristic of N2 neutrophils. Furthermore, liver N2 neutrophils also were observed in ATP7B-knockout mice, and pharmacologically targeted transforming growth factor β1, DNA methyltransferase, or signal transducer and activator of transcription 3 reduces liver N2 neutrophils and improves liver function and alleviates liver inflammation and fibrosis in ATP7B-knockout mice. Epigenetic silencing of Socs3 expression by transforming growth factor β1 contributes to N2-neutrophil polarization in isolated bone marrow neutrophils.

CONCLUSIONS

Our findings provide a novel prospect that pharmacologic modulation of N2-neutrophil activity should be explored as an alternative therapeutic to improve liver function in Wilson's disease.

Blood Based Biomarkers of Central Nervous System Involvement in Wilson's Disease

Wilson's disease (WD) is an inherited disorder of copper metabolism with clinical symptoms related to pathological copper accumulation, which are mainly hepatic and/or neuropsychiatric. The disease is potentially treatable with pharmacological agents (chelators or zinc salts). As such, key factors for a favorable treatment outcome are early diagnosis and anti-copper treatment initiation as well as appropriate treatment monitoring for safety and efficacy. Despite the generally favorable outcome in most treated patients, almost 10% of the general population of WD patients and about 25% of patients in the group with initial neurological phenotype of disease experience early neurological deterioration. In almost 50% of patients with neurological symptoms, the symptoms persist. A search for new treatment modalities (e.g., gene therapy, molybdenum salts) aims to prevent early neurological deterioration as well as improve treatment outcomes. In addition to evaluating the clinical signs and symptoms of the disease, serum biomarkers for diagnosis and treatment monitoring are very important for WD management. Sensitive serum biomarkers of copper metabolism and liver injury are well described. However, there is a need to establish blood-based biomarkers of central nervous system (CNS) injury to help identify patients at risk of early neurological deterioration and aid in their monitoring. Based on the available literature and studies of WD patients, the authors reviewed serum biomarkers of CNS involvement in WD, as well as their potential clinical significance.

Full-length ATP7B reconstituted through protein trans-splicing corrects Wilson disease in mice

Wilson disease (WD) is a genetic disorder of copper homeostasis, caused by deficiency of the copper transporter ATP7B. Gene therapy with recombinant adeno-associated vectors (AAV) holds promises for WD treatment. However, the full-length human ATP7B gene exceeds the limited AAV cargo capacity, hampering the applicability of AAV in this disease context. To overcome this limitation, we designed a dual AAV vector approach using split intein technology. Split inteins catalyze seamless ligation of two separate polypeptides in a highly specific manner. We selected a DnaE intein from Nostoc punctiforme (Npu) that recognizes a specific tripeptide in the human ATP7B coding sequence. We generated two AAVs expressing either the 5′-half of a codon-optimized human ATP7B cDNA followed by the N-terminal Npu DnaE intein or the C-terminal Npu DnaE intein followed by the 3′-half of ATP7B cDNA, under the control of a liver-specific promoter. Intravenous co-injection of the two vectors in wild-type and Atp7b^−/− mice resulted in efficient reconstitution of full-length ATP7B protein in the liver. Moreover, Atp7b^−/− mice treated with intein-ATP7B vectors were protected from liver damage and showed improvements in copper homeostasis. Taken together, these data demonstrate the efficacy of split intein technology to drive the reconstitution of full-length human ATP7B and to rescue copper-mediated liver damage in Atp7b^−/− mice, paving the way to the development of a new gene therapy approach for WD.

The Role of Zinc in the Treatment of Wilson’s Disease

Wilson’s disease (WD) is a hereditary disorder of copper metabolism, producing abnormally high levels of non-ceruloplasmin-bound copper, the determinant of the pathogenic process causing brain and hepatic damage and dysfunction. Although the disease is invariably fatal without medication, it is treatable and many of its adverse effects are reversible. Diagnosis is difficult due to the large range and severity of symptoms. A high index of suspicion is required as patients may have only a few of the many possible biomarkers. The genetic prevalence of ATP7B variants indicates higher rates in the population than are currently diagnosed. Treatments have evolved from chelators that reduce stored copper to zinc, which reduces the toxic levels of circulating non-ceruloplasmin-bound copper. Zinc induces intestinal metallothionein, which blocks copper absorption and increases excretion in the stools, resulting in an improvement in symptoms. Two meta-analyses and several large retrospective studies indicate that zinc is equally effective as chelators for the treatment of WD, with the advantages of a very low level of toxicity and only the minor side effect of gastric disturbance. Zinc is recommended as a first-line treatment for neurological presentations and is gaining acceptance for hepatic presentations. It is universally recommended for lifelong maintenance therapy and for presymptomatic WD.

Sleep disturbances in newly diagnosed treatment-naïve patients with Wilson's disease

Introduction

Most neurodegenerative and chronic liver disorders are associated with sleep disturbances (SD). SD may be expected to occur in patients with Wilson’s disease (WD), an inherited disorder of copper metabolism that mostly affects the liver and brain; however, there is a lack of observations, particularly in treatment-naïve WD patients.

Methods

We evaluated SD in 19 newly diagnosed treatment-naïve WD patients. All patients completed the Beck Depression Inventory (BDI), the Athens Insomnia Scale (AIS) and the Epworth Sleepiness Scale (ESS), and underwent nightlong video polysomnography (vPSG). Results of vPSG in WD patients were compared with results from 19 sex- and age-matched healthy controls.

Results

Depressive symptoms were not reported by patients on routine examination although three patients were diagnosed with mild depression. No patients reported SD during routine examination; three patients had insomnia according to the AIS and all patients scored 0 on the ESS. Despite the lack of reporting of SD by patients, significant differences were observed between WD patients and controls following vPSG analysis: WD patients had shorter mean total sleeping time (366.2 vs. 451.7 min), a lower percentage of rapid-eye movement (15.4 vs. 20.6%), longer sleep latency (36.7 vs. 10.4 min) and lower sleep efficiency (76.2 vs. 93.8%) (all P ≤ 0.01). SD tended to be worse in patients with neurological WD compared with hepatic WD.

Conclusions

As SD may precede depression and severely affect quality of life, our findings suggest that patients with WD should be screened for SD with suitable methods.

Practical insights into chronic management of hepatic Wilson’s disease

Wilson’s disease (WD) is a rare inherited disorder of human copper metabolism, with an estimated prevalence of 1:30000-1:50000 and a broad spectrum of hepatic and neuropsychiatric manifestations. In healthy individuals, the bile is the main route of elimination of copper. In WD patients, copper accumulates in the liver, it is released into the bloodstream, and is excreted in urine. Copper can also be accumulated in the brain, kidneys, heart, and osseous matter and causes damage due to direct toxicity or oxidative stress. Hepatic WD is commonly but not exclusively diagnosed in childhood or young adulthood. Adherent, non-cirrhotic WD patients seem to have a normal life expectancy. Nevertheless, chronic management of patients with Wilson’s disease is challenging, as available biochemical tests have many limitations and do not allow a clear identification of non-compliance, overtreatment, or treatment goals. To provide optimal care, clinicians should have a complete understanding of these limitations and counterbalance them with a thorough clinical assessment. The aim of this review is to provide clinicians with practical tools and suggestions which may answer doubts that can arise during chronic management of patients with hepatic WD. In particular, it summarises current knowledge on Wilson’s disease clinical and biochemical monitoring and treatment. It also analyses available evidence on pregnancy and the role of low-copper diet in WD. Future research should focus on trying to provide new copper metabolism tests which could help to guide treatment adjustments.

Comparison of the Effectiveness and Safety of d-Penicillamine and Zinc Salt Treatment for Symptomatic Wilson Disease: A Systematic Review and Meta‐Analysis

Background: Pharmacological therapy is currently the main treatment method for patients with Wilson disease (WD). We aimed to evaluate the efficacy and safety of the common treatment regimens in these patients.

Methods: We conducted a systemic review and meta-analysis by searching multiple databases for studies from inception to October 2021. Outcomes of interest were the improved rate and safety of d-penicillamine and zinc salts treatment in WD patients. Two independent reviewers performed the study selection and data extraction.

Results: Sixteen studies were included in this meta-analysis. The pooled improved rate for all included symptomatic WD patients was 78.0% (95% CI: 70.8%–85.2%). In symptomatic hepatic WD patients, there is no difference in the treatment efficiency of d-penicillamine and zinc salts (RR: 0.98, 95% CI: 0.86%–1.12%; p = 0.765). In neurological WD patients, the pooled improved rate of those who received d-penicillamine and zinc salts was 56.3% (95% CI: 37.5%–75.1%) and 80.2% (95% CI: 67.2%–93.2%), respectively. The incidence of adverse effects (RR: 2.42, 95% CI: 1.20%–4.88%; p = 0.014) and neurological deterioration (RR: 1.96, 95% CI: 1.31%–2.93%; p = 0.001) in all symptomatic WD patients treated with d-penicillamine was both higher than that of patients treated with zinc salts.

Conclusion: Our analysis suggests that symptomatic WD patients treated with d-penicillamine have higher incidence of adverse effects and neurological deterioration than that of zinc salts. The therapeutic effectiveness of these two regimens does not seem to be significantly different, and these results must be interpreted with caution.

Systematic Review Registration: PROSPERO registration, identifier CRD 42021287126.

Adverse Events with D-penicillamine Therapy in Hepatic Wilson's Disease: A Single-Center Retrospective Audit

BACKGROUND AND OBJECTIVE: There are limited data on the adverse events of D-penicillamine in Wilson's disease (WD) that can result in dose modification or treatment discontinuation. The objective of this study was to observe the adverse events related to D-penicillamine in patients with hepatic WD.

METHODS

A retrospective audit of prospectively registered hepatic WD patients at a tertiary care center between December 2006 and January 2020 was carried out. Demographic variables, laboratory parameters, and details of treatment were noted. Adverse events (AEs) related to D-penicillamine treatment, the timing and management of these AEs were analysed.

RESULTS

The study included 112 patients with hepatic WD on D-penicillamine. D-penicillamine intolerance was seen in 28/112 (25%) over 179 person-years. Of the 28 AEs, severe AEs leading to permanent D-penicillamine discontinuation occurred in 16 (57%) [never reintroduced 12 (43%), discontinued after intolerant to rechallenge, 4 (14%)], temporary cessation followed by reintroduction to initial dose 13 (46%) and continuation with reduced dose in 3 (11%) patients. Overall, most common AEs were hematological [16, 57% (pancytopenia n = 8, bicytopenia n = 5 and hemolytic anemia n = 3)] while renal adverse events (n = 7, 25%) constituted the most common indication for permanent discontinuation. Cytopenias developed beyond 12 months of D-penicillamine initiation whereas hemolytic anemia developed within first 3 months. Following D-penicillamine discontinuation in 25 patients, it was reintroduced to initial dose in 13/25 (52%), switched to trientine due to neurological worsening in 2/25 (8%) and switched to zinc in 10/25 (40%). In patients with reintroduction, gradual dose escalation was tolerated in 9/13 (69%) with a recurrence of AEs leading to permanent discontinuation in 4/13 (31%).

CONCLUSION

D-penicillamine treatment is associated with significant AEs mainly related to blood, kidney, and skin. Temporary cessation of drug with reintroduction at a lower dose is an effective and safe option.

Chelation therapy in liver diseases of childhood: Current status and response

Chelation is the mainstay of therapy in certain pediatric liver diseases. Copper and iron related disorders require chelation. Wilson’s disease (WD), one of the common causes of cirrhosis in children is treated primarily with copper chelating agents like D-penicillamine and trientine. D-Penicillamine though widely used due its high efficacy in hepatic WD is fraught with frequent adverse effects resulting discontinuation. Trientine, an alternative drug has comparable efficacy in hepatic WD but has lower frequency of adverse effects. The role of ammonium tetra-thiomolybdate is presently experimental in hepatic WD. Indian childhood cirrhosis is related to excessive copper ingestion, rarely seen in present era. D-Penicillamine is effective in the early part of this disease with reversal of clinical status. Iron chelators are commonly used in secondary hemochromatosis of liver in hemolytic anemias. There are strict chelation protocols during bone marrow transplant. The role of iron chelation in neonatal hemochromatosis is presently not in vogue due to its poor efficacy and availability of other modalities of therapy. Hereditary hemochromatosis is rare in children and the use of iron chelators in this condition is limited.

Pediatric Wilson's Disease: Phenotypic, Genetic Characterization and Outcome of 182 Children in France

OBJECTIVES

To describe a cohort of Wilson disease (WD) pediatric cases, and to point out the diagnostic particularities of this age group and the long-term outcome.

METHODS

Clinical data of 182 pediatric patients included in the French WD national registry from 01/03/1995 to 01/06/2019 were gathered.

RESULTS

Diagnosis of WD was made at a mean age of 10.7 ± 4.2 years (range 1-18 years). At diagnosis, 154 patients (84.6%) had hepatic manifestations, 19 (10.4%) had neurological manifestations, and 9 patients (4.9%) were asymptomatic. The p.His1069Gln mutation was the most frequently encountered (14% of patients).Neurological patients were diagnosed at least 1 year after they presented their first symptoms. At diagnosis, the median urinary copper excretion (UCE) was 4.2 μmol/24 hours (0.2-253). The first-line treatment was d-penicillamine (DP) for 131 (72%) patients, zinc salts for 24 (13%) patients, and Trientine for 17 (9%) patients. Liver transplantation was performed in 39 (21.4%) patients, for hepatic indications in 33 of 39 patients or for neurological deterioration in 6 of 39 patients, mean Unified Wilson's Disease Rating Scale of the latter went from 90 ± 23.1 before liver transplantation (LT) to 26.8 ± 14.1 (P < 0.01) after a mean follow-up of 4.3 ± 2.5 years. Overall survival rate at 20 years of follow-up was 98%, patient and transplant-free combined survival was 84% at 20 years.

CONCLUSION

Diagnosis of WD can be challenging in children, particularly at the early stages of liver disease and in case of neurological presentation; hence the support of clinical scores and genetic testing is essential. Diagnosis at early stages and proper treatment ensure excellent outcomes, subject to good long-term treatment compliance. LT is a valid option for end-stage liver disease not responding to treatment and can be discussed for selected cases of neurological deterioration.

Safety of treating acute liver injury and failure

INTRODUCTION

Acute liver injury and progression to acute liver failure can be life-threatening conditions that require prompt careful clinical assessment and therapeutic management.

AREAS COVERED

The aim of this article is to review the safety and side effect profile of pharmacological therapies used in the treatment of acute liver injury with specific focus on hepatic toxicity. We performed an extensive literature search with the terms 'acute liver injury,' 'acute liver failure,' 'therapy,' 'safety,' 'adverse reactions' and 'drug induced liver injury.' A thorough discussion of the main drugs and devices used in patients with acute liver injury and acute liver failure, its safety profile and the management of complications associated to therapy of these conditions is presented.

EXPERT OPINION

Several pharmacological approaches are used in acute liver injury and acute liver failure in an empirical basis. Whilst steroids are frequently tried in serious drug-induced liver injury there is concern on a potential harmful effect of these agents because of the higher mortality in patients receiving the drug; hence, statistical approaches such as propensity score matching might help resolve this clinical dilemma. Likewise, properly designed clinical trials using old and new drugs for subjects with serious drug-induced liver injury are clearly needed.

Hyaluronate/black phosphorus complexes as a copper chelating agent for Wilson disease treatment

Background

Wilson disease (WD) is a genetic disorder of copper storage, resulting in pathological accumulation of copper in the body. Because symptoms are generally related to the liver, chelating agents capable of capturing excess copper ions after targeted delivery to the liver are highly required for the treatment of WD.

Methods

We developed hyaluronate-diaminohexane/black phosphorus (HA-DAH/BP) complexes for capturing copper ions accumulated in the liver for the treatment of WD.

Results

HA-DAH/BP complexes showed high hepatocyte-specific targeting efficiency, selective copper capturing capacity, excellent biocompatibility, and biodegradability. HA enhanced the stability of BP nanosheets and increased copper binding capacity. In vitro cellular uptake and competitive binding tests verified targeted delivery of HA-DAH/BP complexes to liver cells via HA receptor mediated endocytosis. The cell viability test confirmed the high biocompatibility of HA-DAH/BP complexes.

Conclusion

HA-DAH/BP complexes would be an efficient copper chelating agent to remove accumulated copper in the liver for the WD treatment.

Long-term outcome of Wilson's disease complicated by liver disease

Background and Aim

Wilson's disease (WD) is a rare inherited disease that causes systemic copper accumulation. This study examined the long‐term course of WD patients with liver disease.

Methods

The 12 patients (9 female patients) enrolled in the study had a median age of 28 years (range: 19–57 years) at their first visit to our hospital. Clinical course and fibrosis markers were assessed in all patients.

Results

The median age at diagnosis was 24 years (range: 5–42 years). One patient had acute liver failure (ALF) and 11 patients had chronic liver disease (CLD, 5 with cirrhosis). The patients were followed‐up for >20 years. The patient with ALF underwent liver transplantation; the postoperative course during the subsequent 20 years was good. Of the six patients with CLD, liver cirrhosis developed in four patients with interrupted chelating therapy. Two of the patients with cirrhosis died; one of these two patients died at 21 years after liver transplantation. However, the remaining patients with continued treatment exhibited a favorable clinical course for 30 years and none developed hepatocellular carcinoma (HCC). The duration of chelation therapy was significantly negatively correlated (P < 0.05) with the fibrosis‐4 index or aspartate aminotransferase to platelet ratio index (APRI) score at the last visit; lower values were indicative of greater treatment success. Patients with an APRI score ≥1.5 had a significantly worse prognosis (P < 0.05).

Conclusion

Long‐term survival of patients with WD was achieved without worsened liver function or carcinogenesis with appropriate treatment. Treatment disruption should be avoided.

Considerations for optimizing Wilson's disease patients' long-term follow-up

Wilson's disease is a sistemic genetic disease caused by the excessive accumulation of copper. The first and main involvement is in the liver, which can range from mild and transient elevation of transaminases to the onset of an overt cirrhosis or acute liver failure. It is known that up to 20-30% of these patients may evolve to liver cirrhosis during follow-up. In clinical practice, liver fibrosis is assessed mainly by using indirect and non-invasive tools (laboratory tests, liver elastography, ultrasound), similar to other prevalent chronic liver diseases. However, despite the fact that liver elastography is a valuable tool in general hepatology, the evidence of its usefulness and accuracy in Wilsońs disease is scarce. This review summarizes the available scientific data and their limitations in Wilson's disease.

D-Penicillamine: The State of the Art in Humans and in Dogs from a Pharmacological and Regulatory Perspective

Chelant agents are the mainstay of treatment in copper-associated hepatitis in humans, where D-penicillamine is the chelant agent of first choice. In veterinary medicine, the use of D-penicillamine has increased with the recent recognition of copper-associated hepatopathies that occur in several breeds of dogs. Although the different regulatory authorities in the world (United States Food and Drugs Administration-U.S. FDA, European Medicines Agency-EMEA, etc.) do not approve D-penicillamine for use in dogs, it has been used to treat copper-associated hepatitis in dogs since the 1970s, and is prescribed legally by veterinarians as an extra-label drug to treat this disease and alleviate suffering. The present study aims to: (a) address the pharmacological features; (b) outline the clinical scenario underlying the increased interest in D-penicillamine by overviewing the evolution of its main therapeutic goals in humans and dogs; and finally, (c) provide a discussion on its use and prescription in veterinary medicine from a regulatory perspective.

Copper Toxicity Is Not Just Oxidative Damage: Zinc Systems and Insight from Wilson Disease

Essential metals such as copper (Cu) and zinc (Zn) are important cofactors in diverse cellular processes, while metal imbalance may impact or be altered by disease state. Cu is essential for aerobic life with significant functions in oxidation-reduction catalysis. This redox reactivity requires precise intracellular handling and molecular-to-organismal levels of homeostatic control. As the central organ of Cu homeostasis in vertebrates, the liver has long been associated with Cu storage disorders including Wilson Disease (WD) (heritable human Cu toxicosis), Idiopathic Copper Toxicosis and Endemic Tyrolean Infantile Cirrhosis. Cu imbalance is also associated with chronic liver diseases that arise from hepatitis viral infection or other liver injury. The labile redox characteristic of Cu is often discussed as a primary mechanism of Cu toxicity. However, work emerging largely from the study of WD models suggests that Cu toxicity may have specific biochemical consequences that are not directly attributable to redox activity. This work reviews Cu toxicity with a focus on the liver and proposes that Cu accumulation specifically impacts Zn-dependent processes. The prospect that Cu toxicity has specific biochemical impacts that are not entirely attributable to redox may promote further inquiry into Cu toxicity in WD and other Cu-associated disorders.

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.

Wilson disease: 30-year data on epidemiology, clinical presentation, treatment modalities and disease outcomes from two tertiary Greek centers

OBJECTIVE

Wilson disease is a rare genetic disorder of copper metabolism with a wide range of clinical presentations. The aim of this study is to describe the 30-year clinical experience in the management of Wilson disease patients followed at two Greek referral centers.

METHODS

A retrospective chart review was performed to identify past and present Wilson disease patients diagnosed during the last 30 years.

RESULTS

Sixty-three patients were included. The median age of diagnosis was 19 (3-59) years, while nine (14%) patients were older than 40 years old. Clinical presentation included asymptomatic liver disease (57.1%), neurological disease (20.6%), overt liver disease (12.7%), acute liver failure (6.3%) and other (3.2%). Kayser-Fleischer rings were detected in 27/62 with a higher frequency in neurologic patients (P < 0.001). Ceruloplasmin values were low in 55/63 with significantly lower values in patients with neurological disease (P = 0.048) and in cirrhotic patients (P = 0.017). Increased 24-hour urine copper was measured in 59/63 patients. D-penicillamine was administered in 56/63 patients (88.8%), followed by trientine (6/63, 9.5%), while one patient needed liver transplantation at baseline. At least one treatment switch was performed in 18 patients. By the end of follow-up, all non-cirrhotic patients (25/25) were stable, 3/23 (13%) cirrhotic developed decompensated liver disease, two developed HCC, three received a liver transplant and two died. Five out of 13 neurologic patients had persisting symptoms despite treatment.

CONCLUSION

Wilson disease presents with a wide spectrum of clinical manifestations and should be investigated even in older patients, as early diagnosis, close follow-up and treatment monitoring usually provide favorable outcomes.

Observation on the changes of clinical symptoms, blood and brain copper deposition in Wilson disease patients treated with dimercaptosuccinic acid for 2 years

OBJECTIVE

To compare the clinical symptoms, brain copper deposition changes of Meso-2,3-dimercaptosuccinic acid (DMSA) and penicillamine therapy in patients with Wilson disease (WD) within 2 years.

METHODS

68 drug-naive patients with WD were enrolled. 10 WD patients treated with zinc gluconate alone were used as the control group. Neurological symptoms were scored using the modified Young Scale. Liver function tests, copper indices and sensitive weighted imaging (SWI) examination were collected. The values of corrected phase (CP) were collected. WD patients were treated with DPA (group 1) or DMSA (group 2) for two years, and followed up every 2 months.

RESULTS

The ratio of neurological improvement in group 2 was higher than that in group 1 (P = 0.029). Higher rate of neurologic worsening was noticed in patients treated with DPA vs DMSA (P = 0.039). The post-treatment neurological score of DMSA group was lower than that of Zn group (P = 0.037). Hepatic function in 63.3% of patients was stable, while 16.7% was improved, and 20% was deteriorated, after DMSA therapy. Urinary copper levels were lower 1 month (p = 0.032), 4 months (p = 0.041), 12 months (p = 0.037) after initiation of treatment in group 2 than in group 1. At the first year of treatment, the CP values in globus pallidus and substantia nigra in group 2 were higher than those in group 1 (P = 0.034,0.039). At the second year of treatment, the CP values of substantia nigra in group 2 were higher (P = 0.041). Discontinuation was more common in patients on DPA therapy (P = 0 0.032).

CONCLUSIONS

DMSA could remove metal from brain tissue faster than DPA. DMSA is effective for neurologic symptoms, while the outcome for hepatic symptoms is not entirely satisfactory. DMSA therapy is better tolerated than DPA.

The molecular mechanisms of copper metabolism and its roles in human diseases

Copper is an essential element in cells; it can act as either a recipient or a donor of electrons, participating in various reactions. However, an excess of copper ions in cells is detrimental as these copper ions can generate free radicals and increase oxidative stress. In multicellular organisms, copper metabolism involves uptake, distribution, sequestration, and excretion, at both the cellular and systemic levels. Mammalian enterocytes take in bioavailable copper ions from the diet in a Ctr1-dependent manner. After incorporation, cuprous ions are delivered to ATP7A, which pumps Cu⁺ from enterocytes into the blood. Copper ions arrive at the liver through the portal vein and are incorporated into hepatocytes by Ctr1. Then, Cu⁺ can be secreted into the bile or the blood via the Atox1/ATP7B/ceruloplasmin route. In the bloodstream, this micronutrient can reach peripheral tissues and is again incorporated by Ctr1. In peripheral tissue cells, cuprous ions are either sequestrated by molecules such as metallothioneins or targeted to utilization pathways by chaperons such as Atox1, Cox17, and CCS. Copper metabolism must be tightly controlled in order to achieve homeostasis and avoid disorders. A hereditary or acquired copper unbalance, including deficiency, overload, or misdistribution, may cause or aggravate certain diseases such as Menkes disease, Wilson disease, neurodegenerative diseases, anemia, metabolic syndrome, cardiovascular diseases, and cancer. A full understanding of copper metabolism and its roles in diseases underlies the identification of novel effective therapies for such diseases.

Wilson Disease: An Overview and Approach to Management

Wilson's disease is one of the few preventable movement disorders in which there are therapies that modify disease progression. This disease is caused by copper overload caused by reduced copper excretion secondary to genetic mutations in the ATP7B gene. Copper overload can lead to a variety of clinical presentations, including neurologic symptoms, liver failure, and/or psychiatric manifestations. There is often a delay in diagnosis of Wilson disease, and awareness of the diagnosis and management is important because of the treatable nature of this condition. This article reviews the clinical presentation, epidemiology, genetics, pathophysiology, diagnosis, and management of Wilson disease.

Switching Pharmacological Treatment in Wilson Disease: Case Report and Recommendations

Background. Available treatments for Wilson disease (WD) prevent longterm complications of copper accumulation. Current anti-copper agents include zinc salts, penicillamine, and trientine. Patients with WD may switch between the agents for a number of reasons. Due to the different mechanisms of action between the copper chelators and zinc salts, transitioning could require a period of overlap and increased monitoring. There are no large studies that investigate the best transition strategies between agents. In this article, we review the treatments for WD and how to monitor for treatment efficacy. Case Summary. The patient had been diagnosed with WD for over 20 years prior to establishing care in our Hepatology Clinic. During his initial course, he was transitioned from penicillamine to zinc due to evidence suggesting penicillamine had greater adverse effects in the long term. Later, he was switched to trientine. His liver enzymes and 24-hour urine copper were monitored. During these years, he intermittently had some financial hardship, requiring him to be on penicillamine rather than trientine. He also had developed acute kidney injury. Overall, his liver disease remained under control and he never had signs of decompensated cirrhosis, but had fluctuations of liver enzymes over the years. Conclusion. Anti-copper treatment for WD has to be tailored to medication side effects profile, patient's chronic and emerging comorbidities, as well as costs. Transitioning regimens is often challenging, and it requires closer monitoring, with no predictors of response.

Persistence with treatment for Wilson disease: a retrospective study

Background

Wilson disease (WD) is genetically induced failure of copper metabolism which can be successfully treated with pharmacological agents. The prognosis for survival in most WD patients is favorable if diagnosis and anti-copper treatment are provided early. Many observations imply that persistence with drug treatment is generally low in patients with chronic diseases, which impact the treatment effectiveness, but such results are very limited in WD. The aim of our study was to assess persistence with treatment among WD patients, to analyze its effect on patient outcome and to identify factors that might be related to persistence.

Methods

170 newly diagnosed, symptomatic patients with WD who started treatment between 1995 and 2005 were analyzed retrospectively to assess treatment non-persistence, which was defined as at least one reported break of more than 3 months or minimum two breaks lasting longer than 2 months. Results were further analyzed according to selected clinical variables.

Results

Only 74.1% of patients were persistent with treatment during the mean 11.7 years of follow up. Treatment persistence closely impacted positive clinical outcomes. In patients classified as persistent, improvement and lack of WD progression were observed more often compared to those classified as non-persistent (29.4 and 68.3% vs. 2.3 and 45.5%; p < 0.001, respectively). In contrast, non-persistent patients presented more often with worsening WD than persistent patients (52.3% vs. 2.4%). Type of WD treatment, gender, phenotypic presentation, adverse events and duration of treatment were not related to treatment persistence. Higher or upper/post-secondary education and a supportive family attitude towards treatment were the most important factors related to persistence.

Conclusions

One quarter of WD patients were not taking anti-copper treatment regularly and this had an important negative effect on clinical outcome. Family support played an important role in treatment persistence.

Comparative effectiveness of common therapies for Wilson disease: A systematic review and meta-analysis of controlled studies

BACKGROUND & AIMS

Wilson disease (WD) is a rare disorder of copper metabolism. The objective of this systematic review was to determine the comparative effectiveness and safety of common treatments of WD.

METHODS

We included WD patients of any age or stage and the study drugs D-penicillamine, zinc salts, trientine and tetrathiomolybdate. The control could be placebo, no treatment or any other treatment. We included prospective, retrospective, randomized and non-randomized studies. We searched Medline and Embase via Ovid, the Cochrane Central Register of Controlled Trials, and screened reference lists of included articles. Where possible, we applied random-effects meta-analyses.

RESULTS

The 23 included studies reported on 2055 patients and mostly compared D-penicillamine to no treatment, zinc, trientine or succimer. One study compared tetrathiomolybdate and trientine. Post-decoppering maintenance therapy was addressed in one study only. Eleven of 23 studies were of low quality. When compared to no treatment, D-penicillamine was associated with a lower mortality (odds ratio 0.013; 95% CI 0.0010 to 0.17). When compared to zinc, there was no association with mortality (odds ratio 0.73; 95% CI 0.16 to 3.40) and prevention or amelioration of clinical symptoms (odds ratio 0.84; 95% CI 0.48 to 1.48). Conversely, D-penicillamine may have a greater impact on side effects and treatment discontinuations than zinc.

CONCLUSIONS

There are some indications that zinc is safer than D-penicillamine therapy while being similarly effective in preventing or reducing hepatic or neurological WD symptoms. Study quality was low warranting cautious interpretation of our findings.

Urinary abnormalities in children and adolescents with Wilson disease before and during treatment with d-penicillamine

BACKGROUND AND AIM

Renal abnormalities can occur at any time point during the course of Wilson disease (WD). We aimed to fill a literature gap in this respect by studying urinary abnormalities in children and adolescents with WD.

METHODS

This study included 60 children with WD presenting to the Pediatric Hepatology Unit, Cairo University. The following data were retrieved from the patients' files including age, sex, liver function tests, serum ceruloplasmin, 24-h urinary copper, serum creatinine, blood urea nitrogen, urinalysis, urinary albumin/creatinine ratio, urinary calcium/creatinine ratio, urinary β2-microglobulin, liver and renal biopsy results when available.

RESULTS

All studied cases had no symptoms related to renal involvement. Microscopic hematuria was detected in 11% and 12% at baseline and within 5 years of therapy, respectively. Moderate microalbuminuria was detected in 34%, 50%, and 33% at baseline, within 5 years and > 5 years after therapy, respectively. Hypercalciuria was detected in 23% at baseline, 34% in those patients treated for up to 5 years and 37.5% > 5 years of therapy. Age and international normalized ratio were significantly higher in patients with high calcium/creatinine ratio compared with those with normal values at initial evaluation. Frequency of elevated urinary β2-microglobulin was 36%, 36%, and 37% in patients at baseline, up to 5 years and > 5 years of therapy, respectively.

CONCLUSION

Asymptomatic urinary abnormalities are present in patients with WD at any time point of the disease and during treatment with d-penicillamine. They have to be searched for, as early intervention may prevent progression to renal insufficiency.

Anterior segment optical coherence tomography (AS-OCT) as a new method of detecting copper deposits forming the Kayser-Fleischer ring in patients with Wilson disease

PURPOSE

Kayser-Fleischer ring pathognomonic for Wilson disease (WD) is formed of corneal copper deposits present predominantly within the anterior chamber angle at the Schwalbe's line. The slit-lamp assessment commonly used as a standard of care cannot detect them early enough, as the angle view is obscured by the corneal limbus. The aim of the research was to evaluate the anterior segment optical coherence tomography (AS-OCT), as objective diagnostic assessment of copper deposits forming KF ring in patients with WD.

METHODS

Twenty-nine subjects (17 women) and twenty-nine controls (14 women) were enrolled and underwent slit lamp and AS-OCT assessment.

RESULTS

Kayser-Fleischer ring was not detected - either with a slit lamp or with AS-OCT - in any of the controls. Fifteen subjects presenting without KF ring at a slit-lamp examination were found to have a KF ring when examined with AS-OCT (p < 0.001), which confirms improved accuracy of AS-OCT, as compared to the slit-lamp examination.

CONCLUSION

Our results support AS-OCT as a diagnostic procedure to offer better objectivity and accuracy as compared to a slit-lamp examination, both at the diagnostic stage and when monitoring changes in KF ring during medical therapy to assess its efficacy and patient compliance.

Clinical management of Wilson disease

The availability of effective therapies distinguishes Wilson disease (WD) from other inherited neurometabolic diseases. The cause of hepatic, neurologic or psychiatric symptoms is copper overload and subsequent copper toxicity. Diagnosed WD patients require life-long pharmacologic therapy that is focused on reversal of copper overload with maintenance of a long-term negative copper balance. This is associated with the rapid control of free or non-ceruloplasmin bound copper that is mostly responsible for acute cytotoxic effects. Currently available therapies can be divided into chelators and zinc salts. They have different mechanisms of action and the onset of efficacy that influences their selection in acute and chronic stages of therapy. We review the use of D-penicillamine and trientine for chelation therapies, including the required monitoring of therapy for its efficacy and possible overtreatment with iatrogenic copper deficiency. Additionally, the use of zinc salts is also discussed, including a possibility of its use for the initial therapy in an acute stage of the disease. Supportive and symptomatic therapies for liver failure and neuropsychiatric symptoms are also reviewed.

Current anti-copper therapies in management of Wilson disease

In Wilson disease (WD) severity of disease can vary widely, depending on time of diagnosis. Early treatment can prevent the development of symptoms in patients. In all patients, lifelong medical treatment is indicated. Currently available medical regimens include the copper chelators for example D-penicillamine (DPA) or trientine (TETA), acting to increase copper excretion and zinc salts (ZS), which reduce copper uptake. In this chapter, we discuss considerations regarding choice of drug and safety limitations.

Wilson's Disease: Clinical Practice Guidelines of the Indian National Association for Study of the Liver, the Indian Society of Pediatric Gastroenterology, Hepatology and Nutrition, and the Movement Disorders Society of India

Clinical practice guidelines for Wilson's disease (WD) have been published by the American Association for the Study of Liver Diseases and European Association for the Study of the Liver in 2008 and 2012, respectively. Their focus was on the hepatic aspects of the disease. Recently, a position paper on pediatric WD was published by the European Society of Pediatric Gastroenterology Hepatology and Nutrition. A need was felt to harmonize guidelines for the hepatic, pediatric, and neurological aspects of the disease and contextualize them to the resource-constrained settings. Therefore, experts from national societies from India representing 3 disciplines, hepatology (Indian National Association for Study of the Liver), pediatric hepatology (Indian Society of Pediatric Gastroenterology, Hepatology and Nutrition), and neurology (Movement Disorders Society of India) got together to evolve fresh guidelines. A literature search on retrospective and prospective studies of WD using MEDLINE (PubMed) was performed. Members voted on each recommendation, using the nominal voting technique. The Grades of Recommendation, Assessment, Development and Evaluation system was used to determine the quality of evidence. Questions related to diagnostic tests, scoring system, and its modification to a version suitable for resource-constrained settings were posed. While ceruloplasmin and 24-h urine copper continue to be important, there is little role of serum copper and penicillamine challenge test in the diagnostic algorithm. A new scoring system - Modified Leipzig score has been suggested with extra points being added for family history and serum ceruloplasmin lower than 5 mg/dl. Liver dry copper estimation and penicillamine challenge test have been removed from the scoring system. Differences in pharmacological approach to neurological and hepatic disease and global monitoring scales have been included. Rising bilirubin and worsening encephalopathy are suggested as indicators predicting need for liver transplant but need to be validated. The clinical practice guidelines provide recommendations for a comprehensive management of WD which will be of value to all specialties.

Characterization of mutation spectrum and identification of novel mutations in ATP7B gene from a cohort of Wilson disease patients: Functional and therapeutic implications

Wilson disease (WD), a copper metabolism disorder, occurs due to the presence of mutations in the gene encoding ATP7B, a protein that primarily facilitates hepatic copper excretion. A better understanding of spectrum and functional significance of ATP7B variants is critical to formulating targeted and personalized therapies. Henceforth, we screened and sequenced 21 exons of ATP7B gene from 50 WD patients and 60 healthy subjects. We identified 28 variants comprising, seven novels in 20% alleles, while eight variations affecting 23% alleles were first time reported in Indian cohort. The c.813C>A, p.(Cys271*) (10%) was the most frequent mutation. Bioinformatics analysis revealed five of seven novel variants viz. c.1600C>A, p.(Pro534Thr); c.1616C>A, p.(Pro539His); c.1924G>T, p.(Asp642Tyr); c.2168G>C, p.(Arg723Thr); c.2174G>C, p.(Arg725Thr) resulted in protein misfolding. Sequence conservation analysis of ATP7B regions containing novel variants documented an evolutionarily conserved nature. Functional analysis of these novel variants in five different cell lines lacking inherent ATP7B expression demonstrated sensitivity to CuCl₂ -treatment, experiencing augmented cellular copper retention and decreased copper excretion as well as ceruloplasmin secretion to that of wildtype-ATP7B expressing cells. Interestingly, pharmacological chaperone 4-phenylbutyrate, a clinically approved compound, partially restored protein function of ATP7B mutants. These findings might enable novel treatment strategies in WD by clinically enhancing the protein expression of mutant ATP7B with residual copper export activity.

WTX101 - an investigational drug for the treatment of Wilson disease

INTRODUCTION

Wilson disease (WD) is a genetic disorder in which excess toxic copper accumulates in the liver, brain, and other tissues leading to severe and life-threatening symptoms. Copper overload can be assessed as non-ceruloplasmin-bound copper non-ceruloplasmin-bound copper (NCC) in blood. Current therapies are limited by efficacy, safety concerns, and multiple-daily dosing. Areas covered: This article reviews the literature on WTX101 (bis-choline tetrathiomolybdate), an oral first-in-class copper-protein-binding agent in development for the treatment of WD. Expert opinion: In a proof-of-concept phase II trial, once-daily WTX101 over 24 weeks rapidly lowered NCC levels and this was accompanied by improved neurological status without apparent initial drug-induced paradoxical worsening, reduced disability, stable liver function, with a favorable safety profile. WTX101 directly removes excess copper from intracellular hepatic copper stores and also forms an inert tripartite complex with copper and albumin in the circulation and promotes biliary copper excretion. These mechanisms may explain the rapid biochemical and clinical improvements observed. A phase III trial of WTX101 is ongoing and results are eagerly awaited to confirm if WTX101 can improve the treatment of this devastating disease.

Wilson's Disease in Children: A Position Paper by the Hepatology Committee of the European Society for Paediatric Gastroenterology, Hepatology and Nutrition

BACKGROUND

Clinical presentations of Wilson's disease (WD) in childhood ranges from asymptomatic liver disease to cirrhosis or acute liver failure, whereas neurological and psychiatric symptoms are rare. The basic diagnostic approach includes serum ceruloplasmin and 24-hour urinary copper excretion. Final diagnosis of WD can be established using a diagnostic scoring system based on symptoms, biochemical tests assessing copper metabolism, and molecular analysis of mutations in the ATP7B gene. Pharmacological treatment is life-long and aims at removal of copper excess by chelating agents as D-penicillamine, trientine, or inhibition of intestinal copper absorption with zinc salts. Acute liver failure often requires liver transplantation. This publication aims to provide recommendations for diagnosis, treatment, and follow-up of WD in children.

METHODS

Questions addressing the diagnosis, treatment, and follow-up of WD in children were formulated by a core group of ESPGHAN members. A systematic literature search on WD using MEDLINE, EMBASE, Cochrane Database from 1990 to 2016 was performed focusing on prospective and retrospective studies in children. Quality of evidence was assessed according to the GRADE system. Expert opinion supported recommendations where the evidence was regarded as weak. The ESPGHAN core group and ESPGHAN Hepatology Committee members voted on each recommendation, using the nominal voting technique.

Insights into the management of Wilson's disease

Wilson's disease is a rare, inherited autosomal recessive disease of copper metabolism, in which the causative gene, ATP7B, results in absent or reduced function of the ATP7B transporter important for biliary excretion of copper and incorporation of copper into caeruloplasmin. Affected patients accumulate excessive copper within the liver, brain and other tissues. A disease mainly of children, adolescents and young adults; clinical features vary from the asymptomatic state to chronic liver disease, acute liver failure, and neuropsychiatric manifestations. Diagnosis requires a high index of suspicion and is based on a combination of clinical signs, biochemical tests, hepatic copper content assay and mutation analysis of the ATP7B gene; to date, there are more than 500 mutations of ATP7B in patients with Wilson's disease. Early recognition and treatment can result in an excellent prognosis whereas untreated disease is almost always fatal. Drug therapies include chelating agents, such as penicillamine or trientine, and zinc salts. Liver transplantation is curative correcting the underlying pathophysiology and is traditionally indicated in acute liver failure or end-stage liver disease refractory to medical therapy. This review provides an overview of various aspects of Wilson's disease including molecular basis of the disease, clinical features, diagnostic and management strategies with their current limitations.

Epidemiology, diagnosis, and treatment of Wilson's disease

Wilson's disease (WD) is an autosomal recessive disease caused by a mutation of the ATP7B gene, resulting in abnormal copper metabolism. The major clinical features of WD include liver disease, neurological disorders, K-F rings, and osteoporosis. The prevalence of WD in China is higher than that in Western countries. Early diagnosis and lifelong treatment will lead to better outcomes. Drugs such as sodium dimercaptosuccinate (Na-DMPS), Zn, and Gandou Decoction can be used to treat WD. Some studies have shown that the combination of traditional Chinese medicine and Western medicine is the best approach to treating WD. In order to identify better treatments, this article describes the specific clinical symptoms of Wilson's disease, its diagnosis, and treatment options.

Psychiatric comorbidity in Wilson's disease

Wilson's disease (WD) is a relatively rare autosomal recessive inherited disorder causing copper accumulation in different organs, mainly the liver and brain. Psychiatric disturbances represent a diagnostic and therapeutic issue in WD. A search for relevant articles was carried out on PubMed/Medline, Scopus, and Google Scholar, for papers focused on psychiatric disorders in WD published between 1985-2016. Ninety-two articles were included in this review, showing the findings from 35 observational and case-control studies and 57 case reports. This study discussed the findings on the prevalence of psychiatric symptoms in WD, their impact on the life of those diagnosed, and the efficacy of available treatments on the psychiatric outcomes of WD. Psychiatric disorders are confirmed frequent in WD, with a high prevalence of mood disorders, and contribute to worse Quality-of-Life and psychosocial outcomes. Because specific therapies for WD lead to a good life expectancy, adherence to medicaments and clinical monitoring should be warranted by a multidisciplinary approach, including a hepathologic, neurologic, and psychiatric careful evaluation and education of those affected and their relatives.

Wilson disease: At the crossroads between genetics and epigenetics-A review of the evidence

Environmental factors, including diet, exercise, stress, and toxins, profoundly impact disease phenotypes. This review examines how Wilson disease (WD), an autosomal recessive genetic disorder, is influenced by genetic and environmental inputs. WD is caused by mutations in the copper-transporter gene ATP7B, leading to the accumulation of copper in the liver and brain, resulting in hepatic, neurological, and psychiatric symptoms. These symptoms range in severity and can first appear anytime between early childhood and old age. Over 300 disease-causing mutations in ATP7B have been identified, but attempts to link genotype to the phenotypic presentation have yielded little insight, prompting investigators to identify alternative mechanisms, such as epigenetics, to explain the highly varied clinical presentation. Further, WD is accompanied by structural and functional abnormalities in mitochondria, potentially altering the production of metabolites that are required for epigenetic regulation of gene expression. Notably, environmental exposure affects the regulation of gene expression and mitochondrial function. We present the "multi-hit" hypothesis of WD progression, which posits that the initial hit is an environmental factor that affects fetal gene expression and epigenetic mechanisms and subsequent "hits" are environmental exposures that occur in the offspring after birth. These environmental hits and subsequent changes in epigenetic regulation may impact copper accumulation and ultimately WD phenotype. Lifestyle changes, including diet, increased physical activity, stress reduction, and toxin avoidance, might influence the presentation and course of WD, and therefore may serve as potential adjunctive or replacement therapies.

Update on the clinical management of Wilson's disease

Wilson's disease (WD), albeit relatively rare, is an important genetic metabolic disease because of highly effective therapies that can be lifesaving. It is a great imitator and requires a high index of suspicion for correct and timely diagnosis. Neurologic, psychiatric and hepatologic problems in WD are very nonspecific, and we discuss the most common clinical phenotypes. The diagnosis remains laboratory based, and here we review the most important challenges and pitfalls in laboratory evaluation of WD, including the emerging role of genetic testing in WD diagnosis. WD is a monogenic disorder but has very high allelic heterogeneity with >500 disease-causing mutations identified, and new insights into phenotype-genotype correlations are also reviewed. The gold standard of therapy is chelation of excessive copper, but many unmet needs exist because of possible clinical deterioration in treated patients and potential adverse effects associated with currently available chelating medications. We also review the most promising novel therapeutic approaches, including chelators targeting specific cell types, cell transplantation and gene therapy.