Current and Emerging Issues in Wilson's Disease

Review article: Hepatic steatosis and its associations with acute and chronic liver diseases

BACKGROUND

Hepatic steatosis is a common finding in liver histopathology and the hallmark of metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), whose global prevalence is rising.

AIMS

To review the histopathology of hepatic steatosis and its mechanisms of development and to identify common and rare disease associations.

METHODS

We reviewed literature on the basic science of lipid droplet (LD) biology and clinical research on acute and chronic liver diseases associated with hepatic steatosis using the PubMed database.

RESULTS

A variety of genetic and environmental factors contribute to the development of chronic hepatic steatosis or steatotic liver disease, which typically appears macrovesicular. Microvesicular steatosis is associated with acute mitochondrial dysfunction and liver failure. Fat metabolic processes in hepatocytes whose dysregulation leads to the development of steatosis include secretion of lipoprotein particles, uptake of remnant lipoprotein particles or free fatty acids from blood, de novo lipogenesis, oxidation of fatty acids, lipolysis and lipophagy. Hepatic insulin resistance is a key feature of MASLD. Seipin is a polyfunctional protein that facilitates LD biogenesis. Assembly of hepatitis C virus takes place on LD surfaces. LDs make important, functional contact with the endoplasmic reticulum and other organelles.

CONCLUSIONS

Diverse liver pathologies are associated with hepatic steatosis, with MASLD being the most important contributor. The biogenesis and dynamics of LDs in hepatocytes are complex and warrant further investigation. Organellar interfaces permit co-regulation of lipid metabolism to match generation of potentially toxic lipid species with their LD depot storage.

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.

Structure and mechanism of the human copper transporting ATPases: Fitting the pieces into a moving puzzle

Human copper transporters ATP7B and ATP7A deliver copper to biosynthetic pathways and maintain copper homeostasis in the cell. These enzymes combine several challenges for structural biology because they are large low abundance membrane proteins with many highly mobile domains and long disordered loops. No method has yet succeeded in solving the structure of the complete fully functional protein. Still, X-ray crystallography, Cryo-EM and NMR helped to piece together a structure based model of the enzyme activity and regulation by copper. We review the structures of ATP7B and ATP7A with an emphasis on the mechanistic insights into the unique aspects of the transport function and regulation of the human copper ATPases that have emerged from more than twenty years of research.

Recent Advances in Metalloproteomics

Interactions between proteins and metal ions and their complexes are important in many areas of the life sciences, including physiology, medicine, and toxicology. Despite the involvement of essential elements in all major processes necessary for sustaining life, metalloproteomes remain ill-defined. This is not only owing to the complexity of metalloproteomes, but also to the non-covalent character of the complexes that most essential metals form, which complicates analysis. Similar issues may also be encountered for some toxic metals. The review discusses recently developed approaches and current challenges for the study of interactions involving entire (sub-)proteomes with such labile metal ions. In the second part, transition metals from the fourth and fifth periods are examined, most of which are xenobiotic and also tend to form more stable and/or inert complexes. A large research area in this respect concerns metallodrug-protein interactions. Particular attention is paid to separation approaches, as these need to be adapted to the reactivity of the metal under consideration.

A rare concomitance of Wilson's disease and systemic lupus erythematosus in a teenage girl: a case report and literature review

Background

Wilson's disease (WD) is an inherited disorder characterized by impaired biliary excretion of copper and excessive copper accumulation in multiple organs, primarily leading to hepatic, neurological, and psychiatric manifestations. The coexistence of WD and systemic lupus erythematosus (SLE) has rarely been reported, posing challenges in accurately diagnosing these two conditions because of overlapping clinical symptoms.

Case presentation

We presented the case of a 17-year-old girl initially suspected of having SLE due to positive anti-nuclear antibodies and lupus anticoagulants, decreased platelet count, hypocomplementemia, and pleural effusion. However, the patient also exhibited an unusual manifestation of decompensated liver cirrhosis, which is not typical of SLE. Further investigation revealed low serum ceruloplasmin levels, high 24-h urine copper levels, the presence of Kayser-Fleischer rings, and a compound heterozygous mutation in the ATP7B gene, confirming the diagnosis of WD.

Conclusion

The co-occurrence of WD and SLE poses a significant diagnostic challenge, often leading to misdiagnosis and delayed diagnosis. Therefore, in patients with well-controlled SLE presenting with unexplained liver fibrosis, neurological involvement, or psychiatric symptoms, it is crucial to consider the possibility of WD. However, further studies are required to elucidate the underlying pathophysiological mechanisms.

Disorders of Copper Metabolism in Children-A Problem too Rarely Recognized

Copper plays an important role in metabolic processes. Both deficiency and excess of this element have a negative effect and lead to pathological conditions. Copper is a cofactor of many enzymatic reactions. Its concentration depends on the delivery in the diet, the absorption in enterocytes, transport with the participation of ATP7A/ATP7B protein, and proper excretion. Copper homeostasis disorders lead to serious medical conditions such as Menkes disease (MD) and Wilson's disease (WD). A mutation in the ATP7A gene is the cause of Menkes disease, it prevents the supply of copper ions to enzymes dependent on them, such as dopamine β-hydroxylase and lysyl oxidase. This leads to progressive changes in the central nervous system and disorders of the connective tissue. In turn, Wilson's disease is an inherited autosomal recessive disease. It is caused by a mutation of the ATP7B gene encoding the ATP7B protein which means excess copper cannot be removed from the body, leading to the pathological accumulation of this element in the liver and brain. The clinical picture is dominated by the liver, neurological, and/or psychiatric symptoms. Early inclusion of zinc preparations and chelating drugs significantly improves the prognosis in this group of patients. The aim of the study is to analyse, based on the latest literature, the following factors: the etiopathogenesis, clinical picture, diagnostic tests, treatment, prognosis, and complications of disease entities associated with copper disturbances: Menkes disease and Wilson's disease. In addition, it is necessary for general practitioners, neurologists, and gastroenterologists to pay attention to these disease entities because they are recognized too late and too rarely, especially in the paediatric population.

Wilson's Disease with Acute Hepatic Onset: How to Diagnose and Treat It

Wilson's disease (WD) with acute onset poses a diagnostic challenge because it is clinically indistinguishable from other acute liver diseases. In addition, serum ceruloplasmin and urinary copper excretion, the first-line diagnostic tools for WD, can show false positive results in the case of acute liver failure, and the diagnostic role of genetic analysis is limited by the time required to perform it. In the case of fulminant onset, there is a clear indication of liver transplantation. "New Wilson Index" is frequently used to discriminate between patients who need liver transplantation versus those who can be successfully managed by medical treatment, but its reliability remains controversial. Timely referral of patients with acute liver failure due to WD may be a key factor in improving patient survival. Although liver transplant very often represents the only chance for such patients, maximum effort should be made to promote survival with a native liver. The management of these aspects of WD is still a matter of debate and will be the subject of this review.