Diagnosis Of Wilson Disease Research Articles

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.

Chapter 4 - Genetic and environmental modifiers of Wilson disease

Wilson disease (WD) is characterized by remarkable variety in its phenotypic presentation. Patients with WD can present with hepatic, neurologic, and psychiatric symptoms combined in different and unpredictable ways. Importantly, no convincing phenotype-genotype correlation has ever been identified, opening the possibility that other genes, aside from ATPase copper-transporting beta (ATP7B), are involved in the pathogenesis of this condition. In addition, modifier genes, or genes that can affect the expression of other genes, may be involved. Clinical and basic science data indicate that environmental and dietary factors can potentially modify gene expression in WD and, consequently, its clinical presentation and course. In particular, previously studied genes include copper metabolism domain-containing 1 (COMMD1), antioxidant 1 copper chaperone (ATOX1), X-linked inhibitor of apoptosis (XIAP), apolipoprotein E (APOE), hemochromatosis (HFE), and 5,10-methylenetetrahydrofolate reductase (MTHFR). Dietary factors include iron and methyl group donors which could affect methionine metabolism and epigenetic mechanisms of gene expression regulation. Most of the work conducted in this field is in its initial stages but it has the potential to change the diagnosis and treatment of WD.

Chapter 10 - Wilson disease: neurologic features

Wilson disease (WD) is a neurodegenerative disorder, which presents as a spectrum of neurologic manifestations that includes tremor, bradykinesia, rigidity, dystonia, chorea, dysarthria, and dysphagia, together with a combination of neurologic symptoms that can easily lead to misdiagnosis. An early diagnosis of WD, and appropriate anticopper treatment, usually leads to a marked improvement in patient health. Conversely, delayed diagnosis can result in persistent pathology, which, left untreated, can ultimately prove lethal. The aim of this chapter is to present a detailed description of the neurologic features of WD, including their evaluation, together with relevant ophthalmologic examinations, brain neuroimaging, and other laboratory measurements that show the extent of the involvement of the nervous system.

Chapter 13 - Other organ involvement and clinical aspects of Wilson disease

Wilson disease (WD) is a rare disorder of copper metabolism that presents mainly with hepatic and neuropsychiatric features. Copper accumulates not only in the liver and brain, but also in other organs. Liver injury can also be the cause of secondary impairment of other tissues. Therefore, the clinical manifestation of WD may be renal, cardiac, skin, osteoarticular, or endocrinologic and include other organ disturbances. Renal abnormalities include tubular dysfunction (e.g., renal tubular acidosis, aminoaciduria) and nephrolithiasis. Bone demineralization is a common manifestation in patients with WD. Cardiac injury may include arrhythmia, cardiomyopathy, and autonomic dysfunction. Different endocrine system manifestations, such as infertility or repeated miscarriages, growth and puberty disturbances, and hypoparathyroidism, are observed. Other important clinical aspects of WD include pancreas involvement, immunologic abnormalities, the presence of lipomas, and skin changes. Although other organ involvement is not common in WD and usually not severe, delayed diagnosis may lead to irreversible changes in organs and tissues. Therefore, awareness of other possible WD presentations is important in the differential diagnosis of WD.

Lipid and copper metabolism in humans with wilson disease: Enigmatic relationship.

Potential conflict of interest: Nothing to report. To the Editor: We read with interest the article by Hamilton et al. published in hepatology, an experimental study highlighting the role of nuclear receptors in a mouse model of Wilson disease (WD).1 Their previous study demonstrated that lipid metabolism was inhibited in response to hepatic copper accumulation in the WD mouse model,2 and this expanded study showed that up‐regulation of the nuclear receptor by liver X receptor agonist administration can increase serum lipid values to normal despite significant hepatic copper overload. These findings seem very convincing and throw light on WD pathogenesis. The only human study describing attenuation in lipid metabolism in WD suggests low cholesterol levels, but the study does not provide correlation of lipids with hepatic copper.3 We had opportunity to retrospectively study serum lipid profiles, liver function tests, and hepatic copper in our WD children (n = 26) seen at King's College Hospital from 2005 to 2015. WD diagnosis was established with ATP7B mutations in all. Serum total cholesterol (TC) and triglyceride (TG) data before starting treatment were collected. Hepatic copper was measured in four explant livers of WD/acute liver failure children and 22 core liver biopsy tissues from WD/non–acute liver failure children. The median age at diagnosis was 10.86 (1.64‐17.26) years, and 62% were female. The median hepatic copper was high (513 [7‐4225] μg/g dry weight liver). Interestingly, the median TC and TG in our study were normal, with values of 4.45 (1.7‐6.3) and 1.3 (0.5‐3.2) mmol/L. Indeed, the median body mass index that might affect the lipid profile level was also normal (19.8 [13.7‐40.7] kg/m2). We further assessed the correlation between serum lipid profiles with hepatic copper and liver function tests. There was no correlation between lipid profiles (TC and TG) and hepatic copper (Fig. 1). TG has no correlation with other parameters, while TC significantly correlates with total bilirubin (r = –0.621, P = 0.001) and alanine aminotransferase (r = 0.422, P = 0.028).Figure 1: The correlation between lipid profiles and hepatic copper content.Our data suggest that low cholesterol in hepatic WD patients might relate to severity of liver disease. Our data on correlation of hepatic copper with cholesterol in children with liver disease are not in keeping with the observation in the animal model. However, we were not able to perform nuclear receptor studies in our patient population, but our finding may be of relevance before applying the data from animal studies to humans.

Intragenic Deletions in ATP7B as an Unusual Molecular Genetics Mechanism of Wilson's Disease Pathogenesis.

Wilson’s disease (WD) is an autosomal recessive disorder caused by mutations in the ATP7B resulting in copper overload in the liver and brain. Direct sequencing is routinely used to confirm WD diagnosis; however, partial and whole gene deletions in the heterozygous state cannot be detected by exon amplification since the normal allele will mask its presence. The aim of the present work was to search for unusual mutational events in the unexplained WD cases and to provide insight into the mechanisms. Out of 1420 clinically and biochemically confirmed WD samples received between 2000 and 2014 for routine mutation analysis, we were unable to detect mutant alleles in 142 samples, after extensive sequencing analysis. We used selective amplification and MLPA to identify the partial gene deletions and identified three different partial gene deletions in seven different families. All three deletions were fully characterized at the DNA sequence level. We report the first hemizygous case with WD due to intragenic deletion in the ATP7B (c.3134_3556+689del). This novel deletion resulted from an excision event mediated by consensus sequences in an AluSq2 repeat element and could be traced to micro homologous end joining (MMEJ). Finally, we determined the prevalence of the three deletions in DNA samples from a multinational group of WD patients. Our results emphasize the need for searching mutant alleles beyond routine methods and highlight that large ATP7B deletions are rare, but account for a detectable proportion in some WD patients. Screening for gene aberrations will further improve mutation detection in patients with unidentified ATP7B mutations presenting with clinical manifestations of WD.

Exchangeable copper: a reflection of the neurological severity in Wilson's disease.

The severity of Wilson's disease (WD) is linked to free copper accumulating in the liver and brain. Exchangeable copper (CuEXC) is a new technique to determine plasmatic copper and is useful in the diagnosis of WD. It is hypothesized that it may also enable a good evaluation of extra-hepatic involvement and its severity. Forty-eight newly diagnosed WD patients were prospectively evaluated using hepatic, neurological, ophthalmological and brain magnetic resonance imaging (MRI) scores. Three phenotypic presentations were distinguished: pre-symptomatic, hepatic and extra-hepatic. CuEXC was determined in addition to standard copper assays before decoppering therapy. Correlations between biological parameters and the different scores were determined and compared in the hepatic and extra-hepatic groups. Extra-hepatic patients had significantly higher CuEXC values than those with the hepatic form (P < 0.0001). The overall ability of CuEXC to separate the two forms was satisfactory, with an area under the curve of 0.883 (95% confidence interval 0.771-0.996) and an optimal threshold for extra-hepatic diagnosis of 2.08 μmol/l (sensitivity 85.7%; specificity 94.1%). In extra-hepatic patients, CuEXC was the only biological marker to be positively correlated with the Unified Wilson Disease Rating Score (r = 0.45, P = 0.016), the Kayser-Fleischer ring score (r = 0.46, P = 0.014) and the brain MRI score (r = 0.38, P = 0.048), but it was not correlated with the hepatic score. Exchangeable copper determination is useful when diagnosing WD as a value >2.08 μmol/l is indicative of the severity of the extra-hepatic involvement. In the case of purely hepatic presentation, atypical or mild neurological signs, it should encourage physicians to search for lesions in the brain and eyes.

MR imaging features of liver involvement by Wilson disease in adult patients.

To describe the magnetic resonance imaging (MRI) presentation of liver involvement in adult patients with Wilson disease (WD) and determine the most indicative appearance of this condition on MRI using a retrospective case-control study. MRI examinations of 23 adult patients with WD (14 men, 9 women; mean age=40.4years) were analyzed by two blinded observers and compared to those obtained in 23 patients with chronic viral hepatitis (14 men, 9 women, mean age=40.4years) who were matched for age, gender and severity of chronic liver disease. Images were qualitatively and quantitatively analyzed with respect to imaging presentation. Comparisons were performed using univariate analysis. Honeycomb pattern of hepatic parenchyma was the most discriminating independent variable for the diagnosis of WD (odds ratio, 17.082; 95% CI 2.092-139.497) (P=0.0081) but had a sensitivity of 43% (10/23; 95% CI 23-66%). Regular liver contours was the other variable that strongly correlated with the presence of liver involvement by WD (odds ratio, 11.939; 95% CI 1.503-94.836) (P=0.0190). The honeycomb pattern is the most discriminating independent variable for the diagnosis of liver involvement by WD but has limited sensitivity. Familiarity with this finding may clarify the cause of diffuse hepatic parenchymal abnormalities in patients with unknown WD.

ATP7B Gene Mutations in Croatian Patients with Wilson Disease.

Wilson disease (WD) is an autosomal recessive disorder of copper metabolism, characterized by its accumulation in tissues which results in hepatic, neurological, and/or psychiatric symptoms. The aim of this study was to investigate the genetics of WD in Croatian patients. Correlation of the clinical presentation subtype and the age at onset of the diagnosis of WD with the ATP7B genotype was investigated in a group of Croatian WD patients. DNA from peripheral blood samples was tested for the p.His1069Gln by direct mutational analysis and other polymorphisms were identified by sequence analysis of coding and flanking intronic regions of ATP7B gene. In the group of 75 WD patients of Croatian origin, 18 different mutations in ATP7B gene were detected, three of which were novel. The p.His1069Gln mutation was most frequent, being detected in 44 Croatian WD patients (58.7%). Most ATP7B mutations (90.4%) were located in exons 5, 8, 13, 14, and 15. Clinical diagnosis of WD was confirmed in 59 patients by detecting mutations on both ATP7B alleles. The age at onset of WD and the type of WD clinical presentation showed no significant correlation with the ATP7B genotype.

Spectrum and Classification of ATP7B Variants in a Large Cohort of Chinese Patients with Wilson's Disease Guides Genetic Diagnosis

Background: Wilson's disease (WD) is an autosomal recessive disorder of copper metabolism caused by ATP7B pathogenic mutations. The symptoms of WD can be effectively prevented if the affected individuals are identified and intervened early. However, clinical utility of this molecular analysis is challenging due to hundreds of variants with various clinical effects in the gene. Here, we aim to describe the spectrum of ATP7B variants and assess their clinical effects in the Han Chinese population.Methods: The ATP7B gene was directly sequenced in 632 unrelated WD patients and 503 unrelated healthy individuals. The effects of identified variants were classified according to the American College of Medical Genetics and Genomics (ACMG) standards and guidelines. Different frequency of variants observed in both cases and controls were tested using Chi-square or Fisher's exact tests.Results: We detected 161 non-synonymous variants in these 632 WD patients, 58 of which were novel. Among these variants, 78, 64, 8, 4, and 7 were classified as 'pathogenic variants', 'likely pathogenic variants', 'variants with uncertain significance', 'likely benign variants', and 'benign variants', respectively. Ninety percent (569/632) of these WD patients can be genetically diagnosed with two or more 'pathogenic' or 'likely pathogenic' variants. The 14 most common disease-causing variants were found at least once in 94% (537/569) of genetically diagnosed patients.Conclusions: These data expand the spectrum of ATP7B variants and facilitate effective screening for ATP7B variants for early diagnosis of WD and development of individualized treatment regimens.

The sunflower cataract in Wilson's disease: pathognomonic sign or rare finding?

The presence of Kayser–Fleischer ring in patients with Wilson’s disease (WD) is well documented and included in diagnostic algorithms; however, data about the occurrence of the second postulated ophthalmological sign of WD, sunflower cataract (SC), are limited and even conflicting. The aim of our study was to verify the occurrence of SC in WD. From January 2010 to May 2015, 81 consecutive, newly diagnosed WD patients underwent detailed ophthalmological examinations, including slit lamp examination with special attention to lens transparency, to verify the presence of SC in WD-naive patients. SC was detected in only one (1.2 %) of the examined WD patients, did not impact visual acuity; moreover, completely disappeared following a year of treatment for WD. SC may be a very rare and reversible ophthalmological manifestation of WD that is observed seldom and only at the time of WD diagnosis. We postulate that a finding of SC in WD patients is an interesting finding that may occur in the course of WD, but it is not a pathognomonic sign of WD.

Common Polymorphisms of ATP7B Gene as a Good Marker in Linkage Analysis in Wilson Disease Patients from Southern Iran

Background: Wilson disease (WD) is caused by numerous pathogenic mutations of the ATP7B gene. There are several mutation screening methods that can be used for the diagnosis and carrier detection of WD, however such methods are costly and time-consuming. Therefore, other diagnostic methods should be used for urgent situations such as prenatal diagnosis. Objective: To report common polymorphisms of ATP7B gene in WD patients from southern Iran to be use in linkage analysis in the WD affected families. Material and methods: Genomic DNA was extracted from 30 patients and PCR was carried out for ATP7B gene. DHPLC was then performed and PCR products with abnormal peak profiles were subjected to direct DNA sequencing. Result: Several patients showed abnormal peak profiles in DHPLC analysis and subsequent sequencing results demonstrated that some polymorphisms were more common in southern Iran. Those were c.1216T>G (exon 2), c.1366C>G (exon 3), c.3419 T>C (exon 16), c.3903 + 6C>T (intron 18) and c.4021+50G>C (intron 19). Conclusion: These common polymorphisms can be used by linkage analysis for the prenatal diagnosis and carrier detection in affected families with Wilson disease.

Delay in Diagnosis of Wilson Disease in Children With Insidious Psychiatric Symptoms: A Case Report and Review of the Literature

Received May 8, 2015; revised July 17, 2015; accepted July 27, 2015. From the Child Study Center, Yale School of Medicine, New Haven CT (HM, AM); Psychiatry, Yale School of Medicine, New Haven CT (PZ). Send correspondence and reprint requests to Hun Millard, M.D., M.A., 230 South Frontage Road, New Haven, CT 06519; e-mail: hun. millard@yale.edu, hunmillard@gmail.com & 2015TheAcademy of PsychosomaticMedicine. Published by Elsevier Inc. All rights reserved. Introduction

Wilson's disease caused by alternative splicing and Alu exonization due to a homozygous 3039-bp deletion spanning from intron 1 to exon 2 of the ATP7B gene

We describe a case of Wilson's disease (WD) diagnosed at 5years after routine biochemical test showed increased aminotransferases. Mutation analysis of the ATP7B gene revealed a 3039-bp deletion in the homozygous state spanning from the terminal part of intron 1 to nt position 368 of exon 2. This deletion results in the activation of 3 cryptic splice sites: an AG acceptor splice site in nt positions 578–579 producing a different breakpoint and removing the first 577 nts of exon 2, an acceptor and a donor splice site in nt positions 20363–4 and 20456–7, respectively, in intron 1, resulting in the activation of a 94-bp cryptic Alu exon being incorporated into the mature transcript. The resulting alternative transcript contains a TAG stop codon in the first amino acid position of the cryptic exon, likely producing a truncated, non-functional protein. This study shows that intron exonization can also occur in humans through naturally occurring gross deletions. The results suggest that the combination of DNA and RNA analyses can be used for molecular characterization of gross ATP7B deletions, thus improving genetic counseling and diagnosis of WD. Moreover these studies help to better establish new molecular mechanisms producing Wilson's disease.

Sunflower cataract: do not forget Wilson's disease

A 41-year-old man with liver cirrhosis of unknown aetiology for 6 years was admitted to our department to confirm the diagnosis of Wilson's disease. He consulted an ophthalmologist who suspected...

Metabolic Liver Diseases: Wilson Disease and alpha 1-Antitrypsin Deficiency

Two significant metabolic diseases of the liver are Wilson disease (WD) and α1-antitrypsin deficiency (AATD). WD is defined as an autosomal recessive disorder caused by mutations in the ATP7B gene of copper metabolism, leading to copper accumulation in multiple organs, notably the liver and brain, with ensuing injury giving way to hepatic and neuropsychiatric symptoms. AATD is also a genetic disorder but is distinguished by the production of a defective protease inhibitor, which leads to hepatic and pulmonary injury. This review of WD and AATD addresses their respective epidemiologies, genetics, pathophysiologies, diagnoses, differential diagnoses, managements, complications, and prognoses. Figures show the pathophysiology, clinical presentation, and liver histology of WD; suggested approaches to the diagnosis of WD, suspected WD, and family screening of first-degree relatives of WD patients; monitoring therapy in WD disease; schematic representation of the α1-antitrypsin (AAT) mechanism of action and polymerization of the Z mutation variant; pathophysiology and clinical presentation of AATD; periodic acid–Schiff–positive diastase-resistant globules in AATD; and suggested approach to AAT diagnosis and management. Tables list the causes of low ceruloplasmin, medications used in WD, and AAT variants and risk of disease. This review contains 12 highly rendered figures, 3 tables, and 167 references.

Myocardial integrated ultrasonic backscatter for early detection of cardiac involvement in patients with Wilson disease.

Videodensitometry is a feasible noninvasive ultrasound tissue characterization method allowing early detection of myocardial changes. This study aimed to investigate ultrasonic backscatter properties of the myocardium in Wilson disease patients. We compared cardiologically asymptomatic Wilson disease patients (W group) (n=18) with age-matched (26.7±9.6 years) healthy controls (C group) (n=15). Diagnosis of Wilson disease was made on the basis of clinical manifestations, family history, and laboratory findings and confirmed by liver biopsy. Transthoracic echocardiographic quantitative texture analysis was performed on data from the septum and left ventricular posterior wall, and mean gray level (MGL) histograms at end-diastole (d) and end-systole (s) were obtained after background correction (c). Cyclic variation index (CVI) was calculated using the formula [(cMGLd - cMGLs) / cMGLd] ×100. There were no significant differences in sex, age, body mass index, heart rate or blood pressure, and conventional echocardiographic parameters between the 2 groups. The cMGLs value of the posterior wall was higher in the W group than in the C group (30.9±2.6 vs. 22.2±2.7, p=0.033). The W group had a significantly lower CVI of the septum than did the C group (-22±4.4% vs. 43.4 ±12.9%, p<0.001), and there was no significant difference in the CVI of the posterior wall (-67.0±15.9% vs. 41.7±18.6%, p=0.32). Abnormalities in two-dimensional echocardiographic grey-level distributions were present in Wilson disease patients. These videodensitometric myocardial alterations were significantly lower in Wilson disease patients than in the controls, and this probably represents an early stage of cardiac involvement.

Low-density oligonucleotide microarrays - A major step in Wilson's disease diagnosis.

Low-density oligonucleotide microarrays - A major step in Wilson's disease diagnosis.

Diagnostic Value of Ceruloplasmin in the Diagnosis of Pediatric Wilson's Disease.

PurposeMeasurement of serum ceruloplasmin level is the first step in screening for Wilson's disease (WD). Despite the rarity of WD in the general population, ceruloplasmin levels are routinely measured through hepatitis screening in both adults and children. Herein, we evaluated the diagnostic value of ceruloplasmin for the diagnosis of WD among children with hepatitis.MethodsWe retrospectively reviewed data on serum ceruloplasmin levels measured as a serologic marker for patients with hepatitis at Asan Medical Center (Seoul, Korea) between from January 2004 to November 2013. The diagnosis of WD was confirmed by the identification of pathogenic variants in the ATP7B gene. To determine the diagnostic accuracy of ceruloplasmin, receiver operation characteristic (ROC) curves were constructed and the area under curve (AUC) were calculated.ResultsMeasurements of serum ceruloplasmin were performed in 2,834 children who had hepatitis. Among these, 181 (6.4%) children were diagnosed with WD. The sensitivity, specificity, and accuracy of a ceruloplasmin level of <20 mg/dL in the discrimination of WD were 93.4%, 84.2%, and 84.8%, respectively. In this study, 418 (14.7%) false-positive cases and 12 (0.4%) false-negative cases were noted. Using a ROC curve, a ceruloplasmin level of ≤16.6 mg/dL showed the highest AUC value (0.956) with a sensitivity of 91.2%, a specificity of 94.9%, and an accuracy of 94.7%.ConclusionThe measurement of serum ceruloplasmin was frequently used for the screening of WD in children, despite a low positive rate. The diagnostic value of ceruloplasmin may be strengthened by adopting a new lower cut-off level.

Noninvasive prenatal testing for Wilson disease by use of circulating single-molecule amplification and resequencing technology (cSMART).

Noninvasive prenatal testing (NIPT) for monogenic diseases by use of PCR-based strategies requires precise quantification of mutant fetal alleles circulating in the maternal plasma. The study describes the development and validation of a novel assay termed circulating single-molecule amplification and resequencing technology (cSMART) for counting single allelic molecules in plasma. Here we demonstrate the suitability of cSMART for NIPT, with Wilson Disease (WD) as proof of concept. We used Sanger and whole-exome sequencing to identify familial ATP7B (ATPase, Cu(++) transporting, β polypeptide) gene mutations. For cSMART, single molecules were tagged with unique barcodes and circularized, and alleles were targeted and replicated by inverse PCR. The unique single allelic molecules were identified by sequencing and counted, and the percentage of mutant alleles in the original maternal plasma sample was used to determine fetal genotypes. Four families with WD pedigrees consented to the study. Using Sanger and whole-exome sequencing, we mapped the pathogenic ATP7B mutations in each pedigree and confirmed the proband's original diagnosis of WD. After validation of cSMART with defined plasma models mimicking fetal inheritance of paternal, maternal, or both parental mutant alleles, we retrospectively showed in second pregnancies that the fetal genotypes assigned by invasive testing and NIPT were concordant. We developed a reliable and accurate NIPT assay that correctly diagnosed the fetal genotypes in 4 pregnancies at risk for WD. This novel technology has potential as a universal strategy for NIPT of other monogenic disorders, since it requires only knowledge of the parental pathogenic mutations.