Urinary copper excretion before and after oral intake of d-penicillamine in parents of patients with Wilson's disease

Wilson disease: the diagnostic challenge and treatment outcomes in a series of 262 cases

BACKGROUND

 Wilson disease (WD) is an autosomal recessive disorder that leads to organ toxicity due to copper overload. Early diagnosis is complicated by the rarity and diversity of manifestations.

OBJECTIVE

 To describe the diagnostic features and response to treatment in our cohort of WD patients.

METHODS

 This was a retrospective analysis of 262 WD patients stratified by clinical presentation, complementary exams, ATP7B genotyping, and response to treatment.

RESULTS

 Symptoms occurred at an average age of 17.4 (7-49) years, and patients were followed up for an average of 9.6 (0-45) years. Patients presented mainly with hepatic (36.3%), neurologic (34.7%), and neuropsychiatric (8.3%) forms. Other presentations were hematologic, renal, or musculoskeletal, and 16.8% of the patients were asymptomatic. Kayser-Fleischer rings occurred in 78.3% of the patients, hypoceruloplasminemia in 98.3%, and elevated cupruria/24h in 73.0%, with an increase after D-penicillamine in 54.0%. Mutations of the ATP7B gene were detected in 84.4% of alleles. Brain magnetic resonance imaging showed abnormalities in the basal ganglia in 77.7% of patients. D-penicillamine was the first choice in 93.6% of the 245 patients, and 21.1% of these patients were switched due to adverse effects. The second-line therapies were zinc and trientine. The therapeutic response did not differ significantly between the drugs (p = 0.2). Nine patients underwent liver transplantation and 82 died.

CONCLUSION

 Wilson disease is diagnosed at a late stage, and therapeutic options are limited. In people under 40 years of age with compatible manifestations, WD could be considered earlier in the differential diagnosis. There is a need to include ATP7B genotyping and therapeutic alternatives in clinical practice.

[Wilson's disease: overview]

Wilson's disease (WD) is an uncommon hereditary disorder caused by a deficiency in the ATP7B transporter. The protein codified by this gene facilitates the incorporation of the copper into ceruloplasmin. Therefore, WD accumulates copper primary in the liver and secondary in other organs, such as the central nervous system. It represents a wide spectrum of disease, ranging from being asymptomatic in some patients to promote an acute liver failure in others. The diagnosis requires a combination of clinical signs and symptoms, as well as some diagnostic tests such as the measurement of serum ceruloplasmin, the urinary excretion of copper, the liver biopsy or the genetic testing. The treatment must be maintained lifelong and includes some drugs such as chelating agents (penicillamine and trientine) and inhibitors of the copper absorption (zinc salts). Lastly, the liver transplant should be an option for patients with end-stage liver disease.

Early Diagnosis of Wilson’s Disease in Children in Southern China by Using Common Parameters

Objective: The aim of the study was to develop the early diagnostic criteria for Wilson’s disease (WD) in young children in southern China by using alanine aminotransferase (ALT) elevation as the first manifestation.

Methods: A cross-sectional retrospective analysis of the clinical data and genetic test results of children with WD in southern China in the past 4 years and the follow-up of their short-term prognosis were performed in this study.

Results: A total of 30 children (5.08 ± 2.06 years old) with elevated ALT as the first manifestation of WD in southern China were enrolled in this study, including 14 females and 16 males. Specifically, in all of the 30 cases (100%), the serum ceruloplasmin (CP) level was decreased, whereas the 24-h urinary copper level was increased. The genetic mutation test of the ATP7B gene was used to confirm the diagnosis. In particular, the two mutation sites, including p.R778L and p.I1148T, had the highest mutation frequencies, approximately 23.0 and 10.7%, respectively. Through follow-up, most of the children had good recovery.

Conclusion: Early diagnosis and treatment of WD would substantially increase the survival rate and have a better prognosis. In addition, in 5-year-old children from southern China, early diagnosis could be performed quickly by referring to the following three parameters: elevated ALT, decreased ceruloplasmin level, and increased 24-h urinary copper level. It lays a foundation for further studies with a larger sample size.

Wilson Disease in Children; Chelation Therapy or Liver Transplantation? A 10-Year Experience from Pakistan

Background

Wilson disease (WD) is a rare genetic disorder with vast clinical presentations and a higher incidence in areas where consanguinity is common. Most patients can be treated with oral chelation, but some require advanced surgical intervention, like liver transplantation (LT). This study aims to review outcomes of WD patients presenting to a tertiary care center over a period of 10 years.

Material/Methods

This retrospective analysis was conducted at Shifa International Hospital, Islamabad, Pakistan. Patients <18 years who were diagnosed with WD per ESPAGHAN guidelines from 2010 to 2020 were included. Presentation, diagnosis, treatment, and LT and its complications were recorded. Follow-ups were recorded, and patients were contacted by phone in cases of interrupted follow-up. Frequencies and percentages of variables were calculated.

Results

A total of 48 patients with WD were identified. Symptomatic disease was seen in 45 patients, with 3 diagnosed on screening. The hepatic form was common (62.2%). Mean age at diagnosis was 9.74 (range 5–17) years, 28 (58.3%) were male, while 17 (35.4%) were female. Urinary copper was increased in all patients (645.82±528.40). Oral treatment with penicillamine was given to 34 (75.5%) patients; 4 (8.9%) died while on oral treatment. Living donor LT was performed in 11 (22.9%) patients, who had a mean King’s Wilson index of 11 (range, 6–14). Currently, all LT patients are alive, with maximum graft survival of 7 years.

Conclusions

LT offers a promising treatment with good outcomes in pediatric WD. However, timely diagnosis and management with oral chelation therapy can prolong survival without LT.

Oxidative stress and neurobehavioural changes in rats following copper exposure and their response to MiADMSA and d-penicillamine

An increase in copper concentration in body may lead to hepatolenticular degeneration which is considered as one clinical feature of Wilson’s disease. Chelation therapy using d-penicillamine is the preferred medical treatment for reducing the toxic effects of copper. However, a few shortcomings associated with d-penicillamine led us to search of an alternative antidote for copper toxicity. Monoisoamyl-2, 3-dimercaptosuccinic acid (MiADMSA), a potent arsenic chelator under clinical trial, has been reported to reduce system copper level. Thus, the present study was envisaged to explore the ameliorative effect of MiADMSA against copper toxicity. Copper pre-exposed animals (CuSO4.5H2O; 100 mg/kg; p.o., for 6 weeks) were segregated in different groups and were administered equimolar dose (0.3 mEq/kg/day; p.o.) of d-penicillamine and MiADMSA for 5 days. The effect of different treatments on spontaneous locomotor activity, muscle coordination, depression like behaviour and contextual fear memory was analysed using neurobehavioural battery test. Biochemical variables related to oxidative stress, zinc and copper concentration were determined in liver, kidney and brain. The results suggested that copper exposure led to oxidative stress in liver, kidney and blood, along with moderate effects in brain. Treatment with d-penicillamine and MiADMSA reduced liver copper load. MiADMSA produced more pronounced beneficial effect compared to d-penicillamine by increasing brain GPx activity. Our study suggests that MiADMSA might be equally effective as d-penicillamine in depleting body copper load. More detailed studies using different doses are required to suggest whether MiADMSA could be an alternative for d-penicillamine in reducing oxidative injury, neurobehavioural changes and depleting body copper burden.

Update on the Diagnosis and Management of Wilson Disease

PURPOSE OF REVIEW

Exciting developments relating to Wilson disease (WD) have taken place with respect to both basic biological and clinical research. This review critically examines some of these findings and considers their implications for current thinking about WD. It is not a comprehensive review of WD as a clinical disorder.

RECENT FINDINGS

The structure of the gene product of ATP7B, abnormal in WD, is being worked out in detail, along with a broader description of how the protein ATP7B (Wilson ATPase) functions in cells including enterocytes, not only in relation to copper disposition but also to lipid synthesis. Recent population studies raise the possibility that WD displays incomplete penetrance. Innovative screening techniques may increase ascertainment. New strategies for diagnosing and treating WD are being developed. Several disorders have been identified which might qualify as WD-mimics. WD can be difficult to diagnose and treat. Insights from its pathobiology are providing new options for managing WD.

Recommendations for provoked challenge urine testing

"Urine mobilization test," "challenge test," and "provoked urine test" are all terms used to describe the administration of a chelating agent to a person prior to collection of their urine to test for metals. There is no standard, validated challenge test. Despite recommendations by professional and government organizations against the use of provoked urine testing, the tests are still commonly used and recommended by some practitioners. Challenge testing utilizes a variety of chelating agents, including dimercaptosuccinic acid (DMSA), dimercaptopropanesulfonate (DMPS), and ethylenediaminetetraacetic acid (EDTA). The agents are given by a variety of routes of administration, doses used are inconsistent, and urine collection procedures vary. Additional problems with challenge tests include comparison of results to inappropriate reference ranges and creatinine correction of urine obtained within hours of chelator administration. Human volunteer studies demonstrate that mercury is detected in the urine of most people even in the absence of known exposure or chelator administration, and that urinary mercury excretion rises after administration of a chelator, regardless of exposure history and in an unpredictable fashion. Studies also demonstrate that challenge testing fails to reveal a "body burden" of mercury due to remote exposure. Chelating agents have been associated with adverse reactions. Current evidence does not support the use of DMPS, DMSA, or other chelation challenge tests for the diagnosis of metal toxicity. Since there are no established reference ranges for provoked urine samples in healthy subjects, no reliable evidence to support a diagnostic value for the tests, and potential harm, these tests should not be utilized.