Prevalence, Incidence, and Treatment Pattern of Wilson's Disease Using National Health Insurance Data From 2010-2020, Korea.

BACKGROUND: Wilson's disease (WD) is an autosomal recessive disorder in which copper (Cu) accumulates in organs, particularly in the liver and central nervous system. This study aimed to investigate the prevalence, incidence, and treatment patterns of WD patients in Korea. METHODS: National Health Insurance System (NHIS) claims data from 2010 to 2020 were analyzed. patients with WD as a primary or additional diagnosis at least once were identified using the International Classification of Diseases (ICD)-10 disease code E83.0 and a record for a registration program for rare intractable diseases in Korea. RESULTS: The average age- and sex-adjusted prevalence and incidence of WD between 2010 and 2020 were 3.06/100,000 and 0.11/100,000, respectively. The mean age of the patients with newly diagnosed WD was 21.0 ± 15.9 years. Among the 622 WD incident cases during the study period, 19.3% of the patients had liver cirrhosis and 9.2% had received liver transplantation. Psychological and neurological diseases were present in 40.7% and 48.1% of the patients, respectively. Regarding the diagnosis of WD, liver biopsy was performed in only 51.6% of new cases. D-penicillamine, trientine, or zinc were prescribed in 81.5% of the incident cases, and the treatment uptake rates decreased with increasing age. CONCLUSION: The prevalence of WD in Korea is 3.06/100,000 and approximately 1,800 patients use medical services annually. A significant proportion of patients are diagnosed at the cirrhotic stage and not treated with Cu-chelating therapeutics, suggesting the need for early diagnosis and adequate treatment to improve prognosis.

Phenotype and molecular characterization of Wilson's disease in Morocco.

BACKGROUND AND STUDY AIMS: In Morocco the prevalence of Wilson disease (WD) and the spectrum of mutations are not known. The aim of the present study was to estimate the prevalence of WD in Morocco, to evaluate the phenotype among a large cohort of WD patients, and to characterize ATP7B variants in a subgroup of WD patients. PATIENTS AND METHODS: We collected data from 226 patients admitted to five university hospital centers in Morocco between 2008 and 2020. The diagnosis was based on clinical manifestations, function tests and biochemical parameters. The genotype was characterized in 18 families diagnosed at the University Hospital Center of Marrakesh, by next generation sequencing. RESULTS: The mean annual prevalence in Morocco was 3.88 per 100,000 and the allele frequency was 0.15 %. Among the 226 patients included (121 males and 105 females), 196 were referred for a hepatic or neurological involvement and 30 were asymptomatic. The mean age at diagnosis was 13 ± 5.1 years (range: 5 - 42 years). Consanguinity was found in 63.3 % of patients. The mean duration of illness was 2.8 ± 1.9 years. Kayser-Fleischer rings were found in 131 (67.9 %) of 193 patients. Among the 196 symptomatic patients, 141/159 (88.7 %) had low serum ceruloplasmin (<0.2 g/L) and a high 24-hours urinary copper (>100 µg/day) was found in 173/182 (95.1 %) patients. The initial treatment was D-penicillamine in 207 patients, zinc acetate in five, zinc sulfate in five, and nine patients were not treated; 60/207 (29 %) patients have stopped treatment. A total of 72 patients died; the mortality rate was 31.9 %. Eight different ATP7B variants were identified among the 18 patients studied, of which two were novel (p.Cys1104Arg and p.Gln1277Hisfs*52), and six previously published (p.Gln289Ter, p.Cys305Ter, p.Thr1232Pro, p.Lys1020Arg, p.Glu583ArgfsTer25 and c.51+4A>T). All informative patients were homozygous for the disease-causing mutation. CONCLUSION: In Morocco, a high prevalence due to consanguinity and a high mortality rate due to the difficulty of diagnosis and lack of treatment were observed in WD patients. NGS sequencing identified new ATP7B variants in WD patients from Morocco.

Epidemiology of Wilson's Disease and Pathogenic Variants of the ATP7B Gene Leading to Diversified Protein Disfunctions.

Wilson's disease (WD) is an autosomal recessive disorder characterized by toxic accumulation of copper in the liver, brain, and other organs. The disease is caused by pathogenic variants in the ATP7B gene, which encodes a P-type copper transport ATPase. Diagnosing WD is associated with numerous difficulties due to the wide range of clinical manifestations and its unknown dependence on the physiological characteristics of the patient. This leads to a delay in the start of therapy and the subsequent deterioration of the patient's condition. However, in recent years, molecular genetic testing of patients using next generation sequencing (NGS) has been gaining popularity. This immediately affected the detection speed of WD. If, previously, the frequency of this disease was estimated at 1:35,000-45,000 people, now, when conducting large molecular genetic studies, the frequency is calculated as 1:7026 people. This certainly points to the problem of identifying WD patients. This review provides an update on the performance of epidemiological studies of WD and describes normal physiological functions of the protein and diversified disfunctions depending on pathogenic variants of the ATP7B gene. Future prospects in the development of WD genetic diagnostics are also discussed.

Severe early-onset Wilson disease caused by a common pathogenic variant in the Bukharan Jewish population in Israel.

BACKGROUND: Wilson disease is caused by pathogenic variants in the ATP7B gene which encodes a copper-transporting ATPase. AIMS: Describe a common founder pathogenic variant among Bukharan Jews and to assess its prevalence, clinical features, and outcome. METHODS: The cohort consisted of patients of Bukharan Jewish descent diagnosed with Wilson disease at a tertiary pediatric medical center in 2013-2018. Clinical and genetic data were collected and analyzed. RESULTS: Six patients from 4 unrelated families who were homozygous for the c.3784G > T p.(Val1262Phe) pathogenic variant in ATP7B were identified. Five presented with elevated aminotransferase levels, and one, with acute liver failure. Mean age at diagnosis was 8.7 years (5-12.5). Serum ceruloplasmin level was extremely low in all patients (1.9-7 mg/dL; mean 3.2(. The variant was identified in a heterozygous state in 5/153 Bukharan Jews; 2/33 from our local exome database and 3/120 healthy unrelated Bukharan Jews in another cohort, for an estimated carrier frequency of ∼1:30. CONCLUSIONS: We report a common founder pathogenic variant in the ATP7B gene among Bukharan Jews associated with severe early-onset Wilson disease. Given the clinical severity, high frequency of the variant, and being a treatable disease, its inclusion in pre-symptomatic screening in the Bukharan Jewish community should be considered. Furthermore, WD should be part of future genetic newborn screening programs in Israel and worldwide, to enable early treatment and prevention of future life-threatening complications.

Epidemiology, treatment and burden of Wilson disease in France: A 10-year analysis of the national health insurance database.

BACKGROUND & AIMS: Wilson disease (WD) is a rare hereditary, debilitating disease that is fatal if untreated. Given its low prevalence, collecting longitudinal information on large cohorts of patients is challenging. Analysis of health insurance databases offers an approach to meet this challenge. The aim of this study was to evaluate longitudinal trends in the presentation and management of patients with WD identified in the French national health insurance database (SNDS). METHODS: This retrospective, longitudinal, observational study identified people with WD in the SNDS database through hospitalisation diagnosis codes and long-term illness status between 2009 and 2019 inclusive. For each patient, data were extracted on hospitalisations, liver transplantation, mortality, WD-specific treatments (d-penicillamine, trientine and zinc), disability status and sick leave. RESULTS: 1,928 patients with WD were identified, of whom 1,520 (78.8%) were analysed. Prevalence of WD in 2019 was estimated as 2.2 cases per 100,000. Of the 670 patients first documented between 2010 and 2019, 76.1% were hospitalised at least once for a mean duration of 4.63±10.6 days. 152 patients (10.0%) underwent liver transplantation and 205 died (13.5%). The mean age at death was 57.9 ± 23.1 years. 665 patients (43.8%) received a WD-specific treatment at least once. 167 patients (17.1%) received a government disability pension and 624 (41.1%) benefited from long-term illness status due to WD. CONCLUSIONS: Unexpectedly, less than half of patients with WD received treatment recommended in practice guidelines, which may contribute to a high disease burden in terms of hospitalisations, disability and reduced life expectancy. Improving treatment rates, building patient awareness of long-term disease impact or developing a new paradigm of treatment could make a significant contribution to reducing the disease burden.

Analysis of mutations spectrum in the ATP7B gene in patients with Wilson disease using massively parallel sequencing.

The study aimed to search for mutations in the ATP7B gene using massively parallel sequencing in patients with Wilson disease in the Tomsk region. For 42 patients with suspected Wilson's disease (aged from 1 to 33 years) was performed molecular genetic analysis. Enrichment of the interest genome regions was carried out by the long-range PCR. DNA libraries with ligated adapters were constructed with Nextera DNA Flex (Illumina, USA) kit. Sequencing was performed on the Illumina MiSeq platform (Illumina, USA). As a result of this work, we identified 9 pathogenic genetic variants. All variants were previously described in the literature and were found in patients with Wilson's disease. Five missense mutations, one splice site mutation, and 3 frameshift mutations were identified. In patients with Wilson's disease in the Tomsk region, the most common variant was c.3207C>A, this variant is the most common both in the Russian Federation and in other European populations. Also, a pathogenic variant c.3036dupC was found, which is probably endemic to the Russian Federation.

Wilson Disease Prevalence: Discrepancy Between Clinical Records, Registries and Mutation Carrier Frequency.

OBJECTIVES: Diagnosis of Wilson disease (WD) is difficult and, as early detection may prevent all symptoms, it is essential to know the exact prevalence to evaluate the cost-efficacy of a screening program. As the number of WD patients was high in our population, we wished to estimate prevalence by determining the carrier frequency for clinically relevant ATP7B mutations. METHODS: To estimate prevalence, screening for the most prevalent mutation was performed in 1661 individuals with ancestry in Gran Canaria, and the frequency of other mutations was estimated from patient records. Alternatively, ATP7B mutations were detected from exomes and genomes from 851 individuals with Canarian ancestry, 236 from Gran Canaria, and a public Spanish exome database. RESULTS: Estimated carrier frequencies in Gran Canaria ranged from 1 in 20 to 28, depending on the method used, resulting in prevalences of 1 case per 1547 to 3140 inhabitants. Alternatively, the estimated affected frequencies were 1 in 5985 to 7980 and 1 in 6278 to 16,510 in the archipelago or mainland Spain respectively. CONCLUSIONS: The number of carriers predicts much higher prevalences than reported, suggesting that WD is underdiagnosed; specific mutations may remain unnoticed due to low penetrance or no signs of disease at all; regional prevalence rather than national prevalence should be considered in cost-efficacy models to approach preventive screening in the asymptomatic population and genetic screening strategies will have to deal with the genetic heterogeneity of ATP7B in the general population and in patients.

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

OBJECTIVE: Complications affect the outcome of patients with cirrhosis. The favorable prognosis of patients with Wilson disease (WD)-related cirrhosis suggests that its complications differ from those of hepatitis B virus (HBV) infection-related cirrhosis. We aimed to delineate the differences in complications between WD-related and HBV-related cirrhosis. METHODS: The electronic-medical data from patients with WD-related and HBV-related cirrhosis were extracted and analyzed. RESULTS: In total, 211 patients with WD-related cirrhosis and 374 patients with HBV-related cirrhosis were enrolled. Most patients with WD progressed to cirrhosis <10 years after disease onset, whereas those with HBV infection often progressed after >10 years. Patients with WD-related cirrhosis had a markedly lower prevalence of ascites (8.5% vs. 38.5%), gastroesophageal varices/variceal bleeding (13.3% vs. 47.6%), renal impairment (0 vs. 7.6%) and primary liver cancer (0 vs. 39.3%; all p < .001) than those with HBV-related cirrhosis. After adjustment for potential confounders, patients with WD-related cirrhosis carried a lower risk of varices/variceal bleeding. CONCLUSIONS: Although patients with WD progressed to cirrhosis much faster, the prevalence of complications from WD-related cirrhosis was low. Patients with WD-related cirrhosis were less likely to develop gastroesophageal varices/variceal bleeding than those with HBV-related cirrhosis.

Metabolic disorders and the risk of cholangiocarcinoma.

Introduction: Cholangiocarcinoma (CCA) is a malignancy which arises from the biliary epithelium. Carcinogenesis of CCA is mainly linked to aberrant glucose metabolism and creation of an immunosuppressive environment around normal biliary epithelium. The incidence of CCA is higher in the East due to Opisthorchis viverrini, an endemic liver fluke. CCA has also be attributed to genetic, metabolic, and lifestyle risk factors.Areas covered: Differences in epidemiological risk factors are associated with varying phenotypes of CCA. Metabolic risk factors include diabetes, obesity, nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH), dyslipidemia, and metabolic syndrome. Inherited metabolic risk factors include Wilson's disease and hemochromatosis. Metabolic disease is associated with a higher risk of CCA, with higher risk for the intrahepatic form. In this review, the authors provide an overview of available evidence regarding metabolic conditions associated with the development of CCA.Expert opinion: Metabolic disease is associated with a higher risk of intrahepatic CCA compared to its extrahepatic or hilar counterpart. As rates of obesity and metabolic syndrome increase, particularly in the West, it is conceivable that the incidence of CCA will also rise in the next years.

Toxic milk mice models of Wilson's disease.

Wilson's disease (WD) is a rare genetic disorder inherited as an autosomal recessive trait. The signs and symptoms of this disease are related to dysfunctional ATP7B protein which leads to copper accumulation and cellular damage. The organs that are most commonly affected by WD are the liver and brain. The dysfunctional ATP7B homolog has previously been identified in many different species, including two naturally occurring murine models called toxic milk mice. The aim of this paper was to compare the toxic milk mouse described by Rauch (tx) to that from Jackson Laboratory (txJ) through a review of studies on these two groups of mice. The two mice strains differ in the type of carried mutation and the phenotype of the disease. The data of the studies showed that the tx mice developed mild chronic hepatitis but suffered severe organ destruction with faster progression to full-liver cirrhosis. No changes were noted in the neurological and behavioral status of this strain despite the described toxic accumulation of copper and neuronal destruction in their brain. On the other hand, though the Jackson toxic milk mice (txJ) also presented chronic hepatitis, the condition was a bit milder with slower progression to end-stage disease. Moreover, hepatocyte suitable to perform neurobehavioral research as their phenotype characterized by tremors and locomotor disabilities better corresponds with the cliniconeurological picture of the humans.

Wilson disease: revision of diagnostic criteria in a clinical series with great genetic homogeneity.

BACKGROUND: Wilson disease is an autosomal recessive disorder of copper metabolism caused by mutations in the ATP7B gene. An early diagnosis is crucial to prevent evolution of the disease, as implantation of early therapeutic measures fully prevents its symptoms. As population genetics data predict a higher than initially expected prevalence, it was important to define the basic diagnostic tools to approach population screening. METHODS: A highly genetically homogeneous cohort of 70 patients, belonging to 50 unrelated families, has been selected as a framework to analyze all their clinical, biochemical and genetic characteristics, to define the disease in our population, with an estimated prevalence of 1 in 12,369, and determine the most useful features that reach diagnostic value. RESULTS: Serum ceruloplasmin below 11.5 mg/dL and cupremia below 60 µg/mL, were the best analytical predictors of the disease in asymptomatic individuals, while cupruria or hepatic copper determination were less powerful. Genetic analysis reached a conclusive diagnosis in all 65 patients available for complete testing. Of them, 48 were carriers of at least one p.Leu708Pro mutant allele, with 24 homozygotes. Nine patients carried a promoter deletion mutation, revealing that extended sequencing beyond the ATP7B gene-coding region is essential. All mutations caused hepatic damage since early ages, increasing its severity as diagnosis was delayed, and neurological symptoms appear. CONCLUSION: Serum ceruloplasmin determination followed by genetic screening would reduce costs and favor the prioritization of non-invasive procedures to reach a definitive diagnosis, even for asymptomatic cases.

Prevalence of Wilson disease based on genome databases in Japan.

BACKGROUND: Wilson disease (WD) is an autosomal recessive disorder caused by mutations in the ATP7B gene. In 1984, Scheinberg and Sternlieb estimated the prevalence of WD to be 1:30 000. However, recent epidemiological studies have reported increasing prevalence rates in different populations. The carrier frequency of ATP7B variants and the prevalence of WD in the Japanese population have not been reported using multiple databases. METHODS: Multiple public databases were used. First, we included mutations in the ATP7B gene that were registered in the Human Gene Mutation Database (HGMD) Professional, where 885 ATP7B variants were identified as pathogenic. Next, we investigated the allele frequencies of these 885 variants in Japanese individuals using the Human Genetic Variation Database (HGVD) and the Japanese Multi Omics Reference Panel (jMorp). RESULTS: Of the 885 variants of ATP7B, 7 and 12 missense and nonsense variants, zero and three splicing variants, and zero and two small deletions were found in the HGVD and in jMorp, respectively. The total allele frequencies of the ATP7B mutations were 0.011 in the HGVD and 0.014 in the jMorp. According to these data, the carrier frequencies were 0.022 (2.2%) and 0.028 (2.8%), respectively, and patient frequencies were 0.000121 (1.21/10 000 individuals) and 0.000196 (1.96/10 000 individuals), respectively. CONCLUSIONS: This is the first study to report the carrier frequency of ATP7B variants and the prevalence of WD in Japan using multiple databases. The calculated prevalence of WD was comparatively higher than that of previous reports, indicating previous underdiagnosis or the existence of less severe phenotypes.

[Screening for carriers of pathogenic genes for methylmalonic acidemia and Wilson's disease in neonates in Qingdao].

Objective: To investigate the carrier frequency of pathogenic genes for methylmalonic acidemia and Wilson's disease in neonates in Qingdao. Methods: In this cross-sectional study, using computer random sampling, 5 020 neonates from the neonatal screening center in Qingdao area from June 2016 to December 2018 were selected, and 5 012 of them were included in the carrier screening study.DNA was extracted from dried blood stain specimens used in the screening of newborns. Multiplex PCR combined with next generation sequencing were used for gene detection of MMACHC gene, MUT gene and ATP7B gene. The carrying rate of hotspots of each gene were calculated, and binomial distribution method was used to calculate 95% confidence interval of pathogenic gene carrying rate. Results: A total of 5 012 neonates completed the screening for carriers of disease-causing genes, of which 5 006 neonates completed the screening of two diseases and the remaining 6 neonates completed the screening of Wilson disease only.For ATP7B gene, the carrier frequency of the 12 hot spot mutations was 1.46% (73/5 012),and the 95% confidence interval was 1.16%-1.83%. For MMACHC gene and MUT gene, carrier frequency of 18 hot spot mutations was 2.50% (125/5 006) , and the 95% confidence interval was 2.10%-2.97%, among which cblC type accounted for 87.2% and the MUT pathogenic gene accounted for 12.8%. Conclusion: The carrier frequency of methylmalonic acidemia and Wilson's disease are both high in the neonatal population in Qingdao.

ATP7B variant penetrance explains differences between genetic and clinical prevalence estimates for Wilson disease.

Wilson disease (WD) is a genetic disorder of copper metabolism caused by variants in the copper transporting P-type ATPase gene ATP7B. Estimates for WD population prevalence vary with 1 in 30,000 generally quoted. However, some genetic studies have reported much higher prevalence rates. The aim of this study was to estimate the population prevalence of WD and the pathogenicity/penetrance of WD variants by determining the frequency of ATP7B variants in a genomic sequence database. A catalogue of WD-associated ATP7B variants was constructed, and then, frequency information for these was extracted from the gnomAD data set. Pathogenicity of variants was assessed by (a) comparing gnomAD allele frequencies against the number of reports for variants in the WD literature and (b) using variant effect prediction algorithms. 231 WD-associated ATP7B variants were identified in the gnomAD data set, giving an initial estimated population prevalence of around 1 in 2400. After exclusion of WD-associated ATP7B variants with predicted low penetrance, the revised estimate showed a prevalence of around 1 in 20,000, with higher rates in the Asian and Ashkenazi Jewish populations. Reanalysis of other recent genetic studies using our penetrance criteria also predicted lower population prevalences for WD in the UK and France than had been reported. Our results suggest that differences in variant penetrance can explain the discrepancy between reported epidemiological and genetic prevalences of WD. They also highlight the challenge in defining penetrance when assigning causality to some ATP7B variants.

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.

Whole-exome sequencing provides insights into monogenic disease prevalence in Northwest Russia.

BACKGROUND: Allele frequency data from large exome and genome aggregation projects such as the Genome Aggregation Database (gnomAD) are of ultimate importance to the interpretation of medical resequencing data. However, allele frequencies might significantly differ in poorly studied populations that are underrepresented in large-scale projects, such as the Russian population. METHODS: In this work, we leveraged our access to a large dataset of 694 exome samples to analyze genetic variation in the Northwest Russia. We compared the spectrum of genetic variants to the dbSNP build 151, and made estimates of ClinVar-based autosomal recessive (AR) disease allele prevalence as compared to gnomAD r. 2.1. RESULTS: An estimated 9.3% of discovered variants were not present in dbSNP. We report statistically significant overrepresentation of pathogenic variants for several Mendelian disorders, including phenylketonuria (PAH, rs5030858), Wilson's disease (ATP7B, rs76151636), factor VII deficiency (F7, rs36209567), kyphoscoliosis type of Ehlers-Danlos syndrome (FKBP14, rs542489955), and several other recessive pathologies. We also make primary estimates of monogenic disease incidence in the population, with retinal dystrophy, cystic fibrosis, and phenylketonuria being the most frequent AR pathologies. CONCLUSION: Our observations demonstrate the utility of population-specific allele frequency data to the diagnosis of monogenic disorders using high-throughput technologies.

Acute onset neurological symptoms in Wilson disease after traumatic, surgical or emotional events: A cross-sectional study.

Acute onset neurological symptoms evoked by traumatic, surgical, or emotional events in Wilson disease (WD) have never been reported and its clinical characteristics are unclear.We aimed to summarize the clinical characteristics of a special WD whose neurological symptoms acutely developed after traumatic, surgical, or emotional events.Retrospective pilot study.Thirty-one patients who had acute onset neurological symptom as an initial presentation of WD or a new presentation of hepatic WD after mild trauma, surgery, or emotional events were retrospectively studied. All patients were followed for half to 1 year after regular anti-copper treatment.The averaged latency for neurological symptom presentation was 2.79 ±â€Š1.21 hours. The most frequent neurological symptoms were tremor (74%) and basal ganglia (BG) lesions were detected on magnetic resonance imaging in all patients. Lesions in other regions were much less frequently detected. Neurological symptom score and its recovery after treatment were correlated with lesion location: BG area and BG plus other brain areas. Neurological symptoms improved in 21 patients who received timely anti-copper treatment but continued to deteriorate in 6 patients who did not accept regular anti-copper treatment for delayed diagnosis.A diagnosis of WD should be considered when adolescents or adults experience acute presentation of extrapyramidal systems after traumatic, surgical, or emotional stimulation. Timely anti-copper therapy usually gives rise to an excellent prognosis.