A Challenging Case of Wilson's Disease

Wilson's disease (WD) is an inherited disorder characterized by the accumulation of copper in various organs, particularly the liver, central nervous system, and cornea. The clinical presentation of WD can vary widely. Diagnosis requires a combination of clinical and biochemical findings. We present a case of a 20-year-old woman who presented to the Emergency Room with progressive motor decline. She exhibited characteristic neurological symptoms and signs, such as hypomimia, bradyphrenia, bradykinesia, dysarthria, sialorrhea, upper limb dystonia, and wing-beating tremor. Ophthalmological examination revealed corneal deposits known as Kayser-Fleischer rings. Laboratory investigations demonstrated low levels of ceruloplasmin and elevated serum copper. Brain MRI showed typical signs of copper deposition in the basal ganglia. The Leipzig criteria were used to confirm the diagnosis. Treatment with penicillamine and zinc acetate resulted in symptom improvement. This case highlights the diverse presentation of WD and the importance of early diagnosis and prompt treatment initiation.

Neurological-Type Wilson Disease: Epidemiology, Clinical Manifestations, Diagnosis, and Management

Wilson disease (WD) is a complex metabolic disorder caused by disruptions to copper regulation within the body, leading to an unregulated accumulation of copper within various tissues. A less understood organ affected by the collection of copper is the brain, which further leads to the generation of oxygen-free radicals and resultant demyelination. Healthcare providers must keep the neurological form of WD in their list of differentials when patients present with diverse neurological manifestations. The initial step to diagnosis will be to distinguish the characteristic disease presentation with a thorough history and physical and neurological examination. A high clinical disease suspicion of WD should warrant further investigation by laboratory workup and imaging modalities to support the clinical findings and confirm the diagnosis of WD. Once a WD diagnosis is established, the healthcare provider should treat the underlying biological process of WD symptomatically. This review article discusses the epidemiology and pathogenesis of the neurological form of WD, its clinical and behavioral implications, diagnostic features, and treatment modalities (current and emerging therapies), further aiding healthcare professionals in early diagnosis and management strategies.

Wilson disease patient with rare heterozygous mutations in ATP7B accompanied by distinctive nocturnal enuresis: A case report

INTRODUCTION

Wilson disease (WD) is an autosomal-recessive disorder of copper metabolism, which exhibits various symptoms due to the combination of environmental and genetic factors. Here, we report a WD patient who displayed distinctive symptom of nocturnal enuresis.

PATIENT CONCERNS

The patient was a 31-year old woman, who recently developed nocturnal enuresis, combined with hand tremors, trouble speaking, and panic disorder at night.

DIAGNOSIS

The patient had been diagnosed with WD by Kayser-Fleischer rings, abnormal copper metabolism, neuropsychiatric symptoms, and magnetic resonance imaging when she was 17. The diagnosis was further confirmed by genetic analysis, which revealed a compound heterozygous mutations in ATP7B gene (c.2195T>C and c.3044T>C). The patient exhibited nocturnal enuresis, but the ambulatory electroencephalogram, routine urinalysis, residual urine detection, color doppler ultrasound of kidney, ureter, and bladder all displayed no abnormality.

INTERVENTIONS

The patient was treated with sodium dimercaptosulphonate, supplemented with Glutathione and Encephalin-inosine.

OUTCOMES

The urinary copper excretion level decreased gradually, and the nocturnal enuresis was alleviated along with the neuropsychiatric symptoms by copper chelation therapy.

CONCLUSION

In this study, we proved that variants c.2195T>C and c.3044T>C is involved in pathogenesis of WD, and revealed that nocturnal enuresis may be a symptom of WD.

Genotype and clinical course in 2 Chinese Han siblings with Wilson disease presenting with isolated disabling premature osteoarthritis: A case report

RATIONALE

Premature osteoarthritis (POA) is a rare condition in Wilson disease (WD). Particularly, when POA is the only complaint of a WD patient for a long time, there would be misdiagnosis or missed diagnosis and then treatment delay.

PATIENT CONCERNS AND DIAGNOSIS

Two Chinese Han siblings were diagnosed as WD by corneal K-F rings, laboratory test, and mutation analysis. They presented with isolated POA during the first 2 decades or more of their disease course, and were of missed diagnosis during that long time. The older affected sib became disabled due to his severe osteoarthritis when he was as young as 38 years old. Two compound heterozygous pathogenic variants c.2790_2792del and c.2621C>T were revealed in the ATP7B gene through targeted next-generation sequencing (NGS).

LESSONS

Adolescent-onset POA could be the only complaint of WD individual for at least 2 decades. Long delay in the treatment of WD's POA could lead to disability in early adulthood. Detailed physical examination, special biochemical test, and genotyping through targeted NGS should greatly reduce diagnosis delay in atypical WD patients with isolated POA phenotype.

Advance in the pathogenesis and treatment of Wilson disease

Wilson disease is an autosomal recessive disorder of copper metabolism. Diagnosis depends primarily on clinical features, biochemical parameters and the presence of the Kayser-Fleischer ring. Genetic analysis for mutations within ATP7B is a convincing diagnostic tool. The traditional treatment for WD includes chelation of excessive copper accumulation and reduction of copper intake. Medical therapy is effective but WD is not yet curable. Liver transplantation is especially helpful for patients who fail to respond to medical therapy or present with fulminant liver failure, although evaluation of its long-term effect are still in need.

Systems biology approach to Wilson's disease

Wilson's disease (WD) is a severe disorder of copper misbalance, which manifests with a wide spectrum of liver pathology and/or neurologic and psychiatric symptoms. WD is caused by mutations in a gene encoding a copper-transporting ATPase ATP7B and is accompanied by accumulation of copper in tissues, especially in the liver. Copper-chelation therapy is available for treatment of WD symptoms and is often successful, however, significant challenges remain with respect to timely diagnostics and treatment of the disease. The lack of genotype-phenotype correlation remains unexplained, the causes of fulminant liver failure are not known, and the treatment of neurologic symptoms is only partially successful, underscoring the need for better understanding of WD mechanisms and factors that influence disease manifestations. Recent gene and protein profiling studies in animal models of WD began to uncover cellular processes that are primarily affected by copper accumulation in the liver. The results of such studies, summarized in this review, revealed new molecular players and pathways (cell cycle and cholesterol metabolism, mRNA splicing and nuclear receptor signaling) linked to copper misbalance. A systems biology approach promises to generate a comprehensive view of WD onset and progression, thus helping with a more fine-tune treatment and monitoring of the disorder.

Hepatocyte GP73 expression in Wilson disease

BACKGROUND/AIMS

Wilson disease (WD) is a disorder of copper transport caused by mutations within the ATP7B gene. WD is phenotypically variable and can present with predominantly hepatic or neurologic manifestations. The mechanisms responsible for this variability are unknown. GP73, a Golgi membrane protein, is expressed in hepatocytes in response to acute and chronic liver disease.

METHODS

Hepatocyte GP73 expression was examined in the livers of WD patients by semiquantitative immunohistochemistry. GP73 mRNA levels were measured in mice with a deletion of the WD gene (Atp7b(-/-)) by real-time PCR, and these values were compared to the concomitant histological abnormalities and previously reported copper levels.

RESULTS

Hepatocyte GP73 expression was more frequently observed in patients with hepatic versus neurologic presentation (79% vs. 30%, p<0.05). Furthermore, GP73 expression was significantly higher (44.7+/-14.0 vs. 2.0+/-0.81, p<0.05) in patients with hepatic phenotype. In Atp7b(-/-) mice, GP73 mRNA was significantly elevated at 20-46 weeks of age, coincident with extensive hepatic inflammation and fibrosis, but not at 6 weeks, when hepatic histology was normal despite significant copper overload. GP73 mRNA levels normalized concomitantly with the resolution of hepatic injury at 60-weeks. However, in tumor-like nodules GP73 was strikingly elevated.

CONCLUSION

Increased hepatocyte GP73 expression is more commonly a feature of hepatic than neurologic WD, and is triggered in response to inflammation, fibrosis, and dysplasia, rather than copper overload.

ATP7B expression in human breast epithelial cells is mediated by lactational hormones

A role for the copper transporter, ATP7B, in secretion of copper from the human breast into milk has previously not been reported, although it is known that the murine ortholog of ATP7B facilitates copper secretion in the mouse mammary gland. We show here that ATP7B is expressed in luminal epithelial cells in both the resting and lactating human breast, where it has a perinuclear localization in resting epithelial cells and a diffuse location in lactating tissue. ATP7B protein was present in a different subset of vesicles from those containing milk proteins and did not overlap with Menkes ATPase, ATP-7A, except in the perinuclear region of cells. In the cultured human mammary line, PMC42-LA, treatment with lactational hormones induced a redistribution of ATP7B from a perinuclear region to a region adjacent, but not coincident with, the apical plasma membrane. Trafficking of ATP7B was copper dependent, suggesting that the hormone-induced redistribution of ATP7A was mediated through an increase in intracellular copper. Radioactive copper ((64)Cu) studies using polarized PMC42-LA cells that overexpressed mAtp7B protein showed that this transporter facilitates copper efflux from the apical surface of the cells. In summary, our results are consistent with an important function of ATP7B in the secretion of copper from the human mammary gland.

Biochemical basis of regulation of human copper-transporting ATPases

Copper is essential for cell metabolism as a cofactor of key metabolic enzymes. The biosynthetic incorporation of copper into secreted and plasma membrane-bound proteins requires activity of the copper-transporting ATPases (Cu-ATPases) ATP7A and ATP7B. The Cu-ATPases also export excess copper from the cell and thus critically contribute to the homeostatic control of copper. The trafficking of Cu-ATPases from the trans-Golgi network to endocytic vesicles in response to various signals allows for the balance between the biosynthetic and copper exporting functions of these transporters. Although significant progress has been made towards understanding the biochemical characteristics of human Cu-ATPase, the mechanisms that control their function and intracellular localization remain poorly understood. In this review, we summarize current information on structural features and functional properties of ATP7A and ATP7B. We also describe sequence motifs unique for each Cu-ATPase and speculate about their role in regulating ATP7A and ATP7B activity and trafficking.

Copper-transporting P-type adenosine triphosphatase (ATP7B) is expressed in human breast carcinoma

This is the first report to show that a copper-transporting P-type adenosine triphosphatase, ATP7B, is expressed in certain breast carcinomas, and a priori knowledge of its expression is important for the choice of therapy. We investigated the hypothesis that ATP7B, which was shown to be associated with cisplatin resistance in vitro, is expressed in certain breast carcinomas. To test this hypothesis, ATP7B expression and protein level were examined in 41 breast carcinomas using RT-PCR and immunohistochemistry. ATP7B gene / protein could be detected in 22.0% (9 / 41) of breast carcinomas and ATP7B gene expression was correlated well with the protein expression. In nine ATP7B-positive tumors, adjacent normal breast tissue was similarly analyzed, revealing that ATP7B is upregulated in breast carcinoma. ATP7B gene expression in poorly differentiated carcinoma was significantly higher than that in well- / moderately differentiated carcinoma (P = 0.012). Furthermore, we found no association between the ATP7B gene / protein expression and that of MDR1, MRP1, LRP and BCRP. These findings suggested that ATP7B gene expression might be a chemoresistance marker for cisplatin in patients with poorly differentiated breast carcinoma.