Clinical correlation of brain MRI and MRS abnormalities in patients with Wilson disease

Acute insomnia as the initial manifestation of Wilson' s disease: A Case Report

BACKGROUND

Wilson's disease (WD) is a rare autosomal recessive disease that causes impaired copper circulation and excretion. The initial manifestations of WD vary clinically, which makes early diagnosis very difficult. Sleep disorders have been described as common symptoms of WD, but the initial manifestations are in rare cases.

CASE REPORT

This study aims to present a patient with acute insomnia as the initial manifestation of WD. Cranial magnetic resonance imaging showed extensive lesions in the bilateral putamen and caudate nucleus, pressure area of corpus callosum, midbrain, and pons. Interestingly, rare but characteristic signs of WD, such as "face of the giant panda," were shown in this case. WD diagnosis was further established by decreased ceruloplasmin level and ATP7B (adenosine-triphosphatase copper transporting beta polypeptide) gene mutations.

CONCLUSIONS

We describe acute insomnia as the initial manifestation of WD in a 21-year-old male patient. Timely diagnosis allows for early copper-eliminating pharmacotherapy, which is of high prognostic importance, as the patient may be more responsive to treatment at this point.

Brain Magnetic Resonance Imaging in Wilson's Disease-Significance and Practical Aspects-A Narrative Review

Wilson's disease (WD) is a genetic disorder of copper metabolism with pathological copper accumulation in many organs, resulting in clinical symptoms, mostly hepatic and neuropsychiatric. As copper accumulates in the brain during WD, and almost 50% of WD patients at diagnosis present with neurological symptoms, neuroimaging studies (especially brain magnetic resonance imaging (MRI)) are part of WD diagnosis. The classical sequences (T1, T2, and fluid-attenuated inversion recovery) were used to describe brain MRI; however, with the development of neuroradiology, several papers proposed the use of new MRI sequences and techniques like susceptibility-weighted images, T2*, diffusion MRI, tractography, volumetric assessment and post-processing brain MRI analysis of paramagnetic accumulation-quantitative susceptibility mapping. Based on these neuroradiological data in WD, currently, brain MRI semiquantitative scale and the pathognomonic neuroradiological brain MRI signs in WD were proposed. Further, the volumetric studies and brain iron accumulation MRI analysis suggested brain atrophy and iron accumulation as biomarkers of neurological WD disease severity. All these results highlight the significance of brain MRI examinations in WD. Due to the extreme progress of these studies, based on the available literature, the authors present the current state of knowledge about the significance, practical aspects, and future directions of brain MRI in WD.

Diagnosis of Wilson Disease and Its Phenotypes by Using Artificial Intelligence

WD is caused by ATP7B variants disrupting copper efflux resulting in excessive copper accumulation mainly in liver and brain. The diagnosis of WD is challenged by its variable clinical course, onset, morbidity, and ATP7B variant type. Currently it is diagnosed by a combination of clinical symptoms/signs, aberrant copper metabolism parameters (e.g., low ceruloplasmin serum levels and high urinary and hepatic copper concentrations), and genetic evidence of ATP7B mutations when available. As early diagnosis and treatment are key to favorable outcomes, it is critical to identify subjects before the onset of overtly detrimental clinical manifestations. To this end, we sought to improve WD diagnosis using artificial neural network algorithms (part of artificial intelligence) by integrating available clinical and molecular parameters. Surprisingly, WD diagnosis was based on plasma levels of glutamate, asparagine, taurine, and Fischer's ratio. As these amino acids are linked to the urea-Krebs' cycles, our study not only underscores the central role of hepatic mitochondria in WD pathology but also that most WD patients have underlying hepatic dysfunction. Our study provides novel evidence that artificial intelligence utilized for integrated analysis for WD may result in earlier diagnosis and mechanistically relevant treatments for patients with WD.

The degeneration changes of basal forebrain are associated with prospective memory impairment in patients with Wilson's disease

INTRODUCTION

Degeneration changes of the basal forebrain (BF) are suggested to play an important role in cognitive impairment and memory loss in patients with Alzheimer's disease and Parkinson's disease. However, little is known about if and how the structure and function of BF are abnormal in Wilson's disease (WD).

METHODS

Here, we employed the structural and resting-state functional magnetic resonance imaging (fMRI) data from 19 WD individuals and 24 healthy controls (HC). Voxel-based morphometry (VBM) and functional connectivity analysis were applied to investigate the structural and functional degeneration changes of BF in WD. Moreover, the linear regression analyses were performed in the patient group to depict the correlations between the aberrant gray volume and functional connectivity of the BF and clinical performances, such as the prospective memory (PM) and mini-mental state examination (MMSE).

RESULTS

VBM analysis showed that compared with HC, the volume of overlapping cell groups of BF termed CH1-3 and CH4 was significantly reduced in WD. Additionally, the decreased functional connectivity of the CH4 was distributed in the bilateral temporal-parietal junction (TPJ), right thalamus, orbitofrontal gyrus (ORB), and left middle cingulate cortex (MCC). The performances of the time-based prospective memory (TBPM) and event-based prospective memory (EBPM) were related to reduced functional connectivity between CH4 and right ORB. Besides, the functional connectivity of left TPJ was also significantly correlated with EBPM in WD.

CONCLUSION

These findings indicated that the degenerative changes of BF may affect PM through the innervation brain function and may help to understand the neural mechanisms underlying cognitive impairment in WD.

Neuropsychiatric Atypical Manifestation in Wilson's Disease: A Case Report and Literature Review

Wilson's disease (WD) is a rare genetic disorder of copper metabolism that often manifests several clinical signs at the time of diagnosis. Typically it affects the liver in the early stages of the disease course and tends to show neuropsychiatric involvement in the later stages. Early diagnosis of WD holds a prognostic value, and an atypical presentation of the disease adds complexities in diagnosis. Even though we need to consolidate further the treatment guidelines for managing psychiatric and neurological symptoms optimally in the patients of WD, identifying signs at the early stages of the disease is crucial to avoid its detrimental effects on the human body. In this case presentation, a patient with no family history of psychiatric condition showed an early onset of neuropsychiatric symptoms without any other clinical signs of WD. Through this clinical case, we emphasize the importance of ruling out WD in patients that predominantly presents with psychiatric symptoms as a lone symptom. It also highlights the possible diagnostic value and significance of the ceruloplasmin level in identifying WD disease in early stages, when other clinical signs are absent, including liver abnormalities.

Aberrant Coupling Between Resting-State Cerebral Blood Flow and Functional Connectivity in Wilson's Disease

Both abnormalities of resting-state cerebral blood flow (CBF) and functional connectivity in Wilson’s disease (WD) have been identified by several studies. Whether the coupling of CBF and functional connectivity is imbalanced in WD remains largely unknown. To assess this possibility, 27 patients with WD and 27 sex- and age-matched healthy controls were recruited to acquire functional MRI and arterial spin labeling imaging data. Functional connectivity strength (FCS) and CBF were calculated based on standard gray mask. Compared to healthy controls, the CBF–FCS correlations of patients with WD were significantly decreased in the basal ganglia and the cerebellum and slightly increased in the prefrontal cortex and thalamus. In contrast, decreased CBF of patients with WD occurred predominately in subcortical and cognitive- and emotion-related brain regions, including the basal ganglia, thalamus, insular, and inferior prefrontal cortex, whereas increased CBF occurred primarily in the temporal cortex. The FCS decrease in WD patients was predominately in the basal ganglia and thalamus, and the increase was primarily in the prefrontal cortex. These findings suggest that aberrant neurovascular coupling in the brain may be a possible neuropathological mechanism underlying WD.

Magnetic resonance imaging findings in diagnosis and prognosis of Wilson disease

Wilson disease (WD) is a rare autosomal recessive disorder characterized by excessive copper deposition in the body, principally in the liver and the brain. There is a wide spectrum of clinical presentations, but the most significant and basic symptoms of the disease can be divided into hepatic, neurologic, and psychiatric manifestations. Magnetic resonance imaging (MRI) provides more detailed anatomical information than computed tomography of the brain, especially of the structure of the basal ganglia and brain stem. In this review, we want to evaluate the correlation between MRI findings and clinical features of WD.

Disorders of metal metabolism

Trace elements are chemical elements needed in minute amounts for normal physiology. Some of the physiologically relevant trace elements include iodine, copper, iron, manganese, zinc, selenium, cobalt and molybdenum. Of these, some are metals, and in particular, transition metals. The different electron shells of an atom carry different energy levels, with those closest to the nucleus being lowest in energy. The number of electrons in the outermost shell determines the reactivity of such an atom. The electron shells are divided in sub-shells, and in particular the third shell has s, p and d sub-shells. Transition metals are strictly defined as elements whose atom has an incomplete d sub-shell. This incomplete d sub-shell makes them prone to chemical reactions, particularly redox reactions. Transition metals of biologic importance include copper, iron, manganese, cobalt and molybdenum. Zinc is not a transition metal, since it has a complete d sub-shell. Selenium, on the other hand, is strictly speaking a nonmetal, although given its chemical properties between those of metals and nonmetals, it is sometimes considered a metalloid. In this review, we summarize the current knowledge on the inborn errors of metal and metalloid metabolism.

Frequency-dependent changes in the amplitude of low-frequency fluctuations in patients with Wilson's disease: a resting-state fMRI study

To investigate the frequency-dependent changes in the amplitude of low-frequency fluctuations (ALFF) in patients with Wilson's disease (WD). Resting-state function magnetic resonance imaging (R-fMRI) were employed to measure the amplitude of ALFF in 28 patients with WD and 27 matched normal controls. Slow-5 (0.01-0.027 Hz) and slow-4 (0.027-0.073 Hz) frequency bands were analyzed. Apart from the observation of atrophy in the cerebellum, basal ganglia, occipital gyrus, frontal gyrus, precentral gyrus, and paracentral lobule, we also found widespread differences in ALFF of the two bands in the medial frontal gyrus, inferior temporal gyrus, insula, basal ganglia, hippocampus/parahippocampal gyrus, and thalamus bilaterally. Compared to normal controls, WD patients had increased ALFF in the posterior lobe of the cerebellum, inferior temporal gyrus, brain stem, basal ganglia, and decreased ALFF in the anterior lobe of the cerebellum and medial frontal gyrus. Specifically, we observed that the ALFF abnormalities in the cerebellum and middle frontal gyrus were greater in the slow-5 than in the slow-4 band. Correlation analysis showed consistently positive correlations between urinary copper excretion (Cu), serum ceruloplasmin (CP) and ALFFs in the cerebellum. Our study suggests the accumulation of copper profoundly impaired intrinsic brain activity and the impairments seem to be frequency-dependent. These results provide further insights into the understanding of the pathophysiology of WD.

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.

Wilson's disease and other neurological copper disorders

The copper metabolism disorder Wilson's disease was first defined in 1912. Wilson's disease can present with hepatic and neurological deficits, including dystonia and parkinsonism. Early-onset presentations in infancy and late-onset manifestations in adults older than 70 years of age are now well recognised. Direct genetic testing for ATP7B mutations are increasingly available to confirm the clinical diagnosis of Wilson's disease, and results from biochemical and genetic prevalence studies suggest that Wilson's disease might be much more common than previously estimated. Early diagnosis of Wilson's disease is crucial to ensure that patients can be started on adequate treatment, but uncertainty remains about the best possible choice of medication. Furthermore, Wilson's disease needs to be differentiated from other conditions that also present clinically with hepatolenticular degeneration or share biochemical abnormalities with Wilson's disease, such as reduced serum ceruloplasmin concentrations. Disordered copper metabolism is also associated with other neurological conditions, including a subtype of axonal neuropathy due to ATP7A mutations and the late-onset neurodegenerative disorders Alzheimer's disease and Parkinson's disease.

Wilson's Disease with Neurological Presentation, without Hepatic Involvement in Two Siblings

Wilson's Disease (WD) is a rare, autosomal, recessive, inborn error of the copper metabolism, which is caused by a mutation in the copper-transporting gene, ATP7B. The presentation is usually neurologic or hepatic, which is seen in 40% of the patients. The diagnosis depends primarily on the clinical features, the biochemical parameters and the presence of the Kayser - Fleischer ring. Here, we are reporting two siblings who were affected by Wilson's disease, with only neurological manifestations, without any hepatic involvement.

Brain proton magnetic spectroscopy in long-term treatment of Wilson's disease patients

We reported the brain proton magnetic resonance spectroscopy (MRS) findings in 27 Wilson's disease (WD) patients treated more than 6 years in neurological (nWD) and hepatic (hWD) subgroups. We investigated four hWD patients, with no improvement and eight with marked improvement; and eight nWD patients with marked improvement and seven with no improvement of clinical status. In nWD patients with improvement the MRS showed significantly higher Cho/Cr, Glx/Cr ratios levels. In hWD patients with no improvement the lower Cho/Cr and in nWD significantly lower NAA/Cr and higher Cho/Cr and Lip/Cr ratios were detected. In nWD patients with improvement the spectroscopic pattern, can be related to gliosis. In patients with no neurological improvement a persistent neuronal dysfunction can occur, perhaps as a result of copper or iron deposition.

Do MRI features distinguish Wilson's disease from other early onset extrapyramidal disorders? An analysis of 100 cases

Magnetic resonance imaging (MRI) is frequently used in the evaluation of various extrapyramidal disorders. Among the plethora of MRI features in Wilson's disease (WD), only "face of the giant panda" sign has been recognized to distinguish WD from other early onset extrapyramidal disorders (EOEPD). To ascertain the value of various MRI features in differentiating neuropsychiatric form of WD from other EOEPD. This retrospective analysis included 100 patients (M:F = 56:44) of EOEPD (5-40 years), who had undergone MRI during Jan'03 to Nov'08. Their clinical features were recorded and the following MR sequences were analyzed: T1WI, T2WI, FLAIR. Fifty-six patients had WD (M:F = 28:30, age at onset: 14 +/- 6.8 years) and 44 had other EOEPD (M:F = 27:17, age at onset: 19 +/- 9.8 years) that included Huntington's disease--4, young-onset Parkinson's disease--7, mitochondrial disorders--2, Hallervorden-Spatz disease--8, non-Wilsonian hepatolenticular degeneration--2, toxic/metabolic disorder--1, and others--20. The duration of illness at the time of MRI was comparable (WD: 3.1 +/- 4.9 years; Other EOEPD: 2.8 +/- 2.4 years). MR signal characteristics varied in topography and severity in both the groups. All the patients of WD had signal abnormalities in MRI, as against 16/44 of the other EOEPD group. The following MR observations were noted exclusively in WD: "Face of giant panda" sign (14.3%), tectal plate hyperintensity (75%), central pontine myelinolysis (CPM)-like abnormalities (62.5%), and concurrent signal changes in basal ganglia, thalamus, and brainstem (55.3%). Besides "Face of giant panda" sign, hyperintensities in tectal-plate and central pons (CPM-like), and simultaneous involvement of basal ganglia, thalamus, and brainstem are virtually pathognomonic of WD.

Wilson's disease: (31)P and (1)H MR spectroscopy and clinical correlation

INTRODUCTION

Proton ((1)H) magnetic resonance spectroscopy (MRS) changes are noted in Wilson's disease (WD). However, there are no studies regarding membrane phospholipid abnormality using (31)P MRS in these patients. We aimed to analyze the striatal spectroscopic abnormalities using (31)P and (1)H MRS in WD.

METHODS

Forty patients of WD (treated, 29; untreated,11) and 30 controls underwent routine MR image sequences and in vivo 2-D (31)P and (1)H MRS of basal ganglia using an image-selected technique on a 1.5-T MRI scanner. Statistical analysis was done using Student's t test.

RESULTS

The mean durations of illness and treatment were 6.2 ± 7.4 and 4.8 ± 5.9 years, respectively. MRI images were abnormal in all the patients. (1)H MRS revealed statistically significant reduction of N-acetyl aspartate (NAA)/choline (Cho) and NAA/creatine ratios in striatum ((1)H MRS) of treated patients compared to controls. The mean values of phosphomonoesters (PME) (p < 0.0001), phosphodiesters (PDE) (p < 0.0001), and total phosphorus (TPh) (p < 0.0001) were elevated in patients compared to controls. Statistically significant elevated levels of ratio of PME/PDE (p = 0.05) observed in the striatum were noted in treated patients as compared to controls in the (31)P MRS study. The duration of illness correlated well with increased PME/PDE [p < 0.001], PME/TPh [p < 0.05], and PDE/TPh [p < 0.05] and decreased NAA/Cho [p < 0.05] ratios. There was correlation of MRI score and reduced NAA/Cho ratio with disease severity. The PME/PDE ratio (right) was elevated in the treated group [p < 0.001] compared to untreated group.

CONCLUSIONS

There is reduced breakdown and/or increased synthesis of membrane phospholipids and increased neuronal damage in basal ganglia in patients with WD.

Role of neuroimaging in the evaluation of tremor

The role for neuroimaging in the management of patients with tremor is gradually increasing, particularly with respect to stereotactic neurosurgery and deep brain stimulation where less than 2-mm tolerance is required for accurate electrode placement. The routine use of single photon emission CT technology to image the nigrostriatal dopaminergic system is proving helpful in distinguishing essential and dystonic tremors from neurodegenerative forms of parkinsonism and in improving our understanding of the pathophysiology of rarer tremors.

Acquired hepatocerebral degeneration

Cirrhosis and its co-morbidities may cause a variety of neurological complications, the most common being bouts of toxic metabolic encephalopathy. A proportion of patients with chronic liver disease develop acquired hepatocerebral degeneration (AHD), a chronic progressive neurological syndrome characterized by parkinsonism, ataxia and other movement disorders. This article reviews the clinical spectrum, pathophysiology, neuroimaging features and differential diagnosis of AHD along with emerging treatment options.

Psychopathology and personality traits in patients with treated Wilson disease grouped according to gene mutations

Wilson disease (WD) is a recessively inherited copper storage disorder mainly affecting liver and brain. Genotype/phenotype correlations have been report ed but as yet not regarding psychic symptoms. Our aim was to investigate if a correlation might exist between genotype and phenotype concerning psychopathology and/or personality traits in patients with treated WD. Nine homozygous and three compound heterozygous Swedish patients were retrospectively investigated, representing four different mutation settings. Psychopathological symptoms were studied using the Comprehensive Psychopathological Rating Scale (CPRS), personality traits using the Karolinska Scales of Personality (KSP) and mutations were analyzed by manifold sequencing. Psychopathological symptoms: Patients with the Trp779Stop mutation had the lowest scores on the total CPRS, due to less pronounced reported CPRS items, as compared to the other three groups of patients. Compound heterozygotes for the His1069Gln/Arg1319Stop mutation showed the highest total CPRS scores. Personality traits: Patients homozygous for the Trp779Stop and the Thr977Met mutations had high scores on Psychopathy related scales whereas patients with His1069Gln/Arg1319Stop mutations had the lowest scores on these scales. Serum ceruloplasmin levels were undetectable in all patients with the Trp779Stop and Thr977Met mutations. The results show a trend towards a genotype/phenotype correlation regarding psychopathological symptoms and personality traits in treated patients with WD. If replicable, these results might contribute to the elucidation of the possible clinical importance of functionally deleterious gene mutations in WD psychopathology and personality traits.

Ocular motility and Wilson's disease: a study on 34 patients

BACKGROUND

Wilson's disease is an autosomal recessive genetic disorder resulting from an abnormality of copper metabolism. The excessive accumulation of copper in the brain induces an extrapyramidal syndrome. Oculomotor abnormalities occur in most extrapyramidal disorders but have rarely been studied in Wilson's disease.

OBJECTIVE

To evaluate the ocular motility manifestations of Wilson's disease.

METHODS

A prospective study of 34 patients affected by Wilson's disease who were recruited and their ocular motility recorded by electro-oculography (EOG).

RESULTS

Vertical smooth pursuit was abnormal in 29 patients (85%). Vertical optokinetic nystagmus and horizontal smooth pursuit were impaired in 41% and 41% of patients, respectively. No MRI abnormality was found in the lenticular nuclei of seven patients who manifested ocular motility abnormalities.

CONCLUSION

Vertical eye movements, in particular vertical pursuits, are impaired in Wilson's disease, more often than vertical optokinetic nystagmus and vertical saccades. EOG abnormalities can be found in patients who do not yet exhibit anatomical lesions on MRI.

Sequential MRI changes in Wilson's disease with de-coppering therapy: a study of 50 patients

Wilson's disease (WD) is clinically and radiologically a dynamic disorder. However, there is a paucity of studies involving sequential MRI changes in this disease with or without therapy This study looked at serial MRI changes and their clinical correlate in patients with WD The severity of MRI changes using 1.5 T MRI in 50 patients with WD was graded based on alteration in signal intensity of focal lesions and atrophy. Details of clinical manifestations, Schwab and England Activities of daily living (MSEADL) score, Neurological Symptom Score (NSS) and Chu staging were recorded. Clinical severity and disability scores were correlated with MRI scores using SPSS v10 The mean age at onset of illness and diagnosis was 12.8+/-5.6 years and 14.4+/-6.0 years, respectively. At the time of first MRI, patients had been treated for 49.0+/-77.3 months. At a follow-up of 24.2+/-12.2 months, clinically 36 patients had improved, 9 remained the same and 5 had worsened. Serial imaging revealed an improvement in MRI parameters in 35 patients, no significant changes in 10, worsening in 4 and an admixture of resolving and evolving changes in 1. The overall MRI score improved from 8.2+/-5.7 to 5.9+/-6.6. There was an improvement in measures of disability and impairment in all: Chu stage, 11.5+/-0.7 to 1.3+/-0.6; MSEADL score (%), 79.7+/-27.6 to 88.0+/-25.4; NSS, 10.6+/-11.2 to 8.0+/-11.6, with good clinico-radiological correlation. Patients with extensive changes, white-matter involvement and severe diffuse atrophy had a poor prognosis In conclusion, the majority of patients with WD showed variable improvement in clinical and MRI features when treated.

Wilson's disease

Progressive hepatolenticular degeneration, or Wilson's disease, is a genetic disorder of copper metabolism. Knowledge of the clinical presentations and treatment of the disease are important both to the generalist and to specialists in gastroenterology and hepatology, neurology, psychiatry, and paediatrics. Wilson's disease invariably results in severe disability and death if untreated. The diagnosis is easily overlooked but if discovered early, effective treatments are available that will prevent or reverse many manifestations of this disorder. Studies have identified the role of copper in disease pathogenesis and clinical, biochemical, and genetic markers that can be useful in diagnosis. There are several chelating agents and zinc salts for medical therapy. Liver transplantation corrects the underlying pathophysiology and can be lifesaving. The discovery of the Wilson's disease gene has opened up a new molecular diagnostic approach, and could form the basis of future gene therapy.

Wilson's disease: an update

Wilson's disease (WD) is an inborn error of copper metabolism caused by a mutation to the copper-transporting gene ATP7B. The disease has an autosomal recessive mode of inheritance, and is characterized by excessive copper deposition, predominantly in the liver and brain. Diagnosis of the condition depends primarily on clinical features, biochemical parameters and the presence of the Kayser-Fleischer ring, and a new diagnostic scoring system has recently been proposed. Mutations in ATP7B can occur anywhere along the entire 21 exons, which makes the identification of gene defects particularly challenging. Identification of carriers and presymptomatic family members of affected individuals is achieved by polymerase-chain-reaction-based marker analysis. The traditional treatment for WD is based on copper chelation with agents such as D-penicillamine, but use of this drug has been questioned because of reported side effects. The use of agents such as trientine and ammonium tetrathiomolybdate has been advocated, although results of long-term trials are awaited. In selected cases, orthotropic hepatic transplantation can reverse the basic metabolic abnormality in WD and improve both hepatic and neurological symptoms. Studies of the underlying defects in ATP7B and its suspected modifiers ATOX1 and COMMD1 are expected to unravel the disease's genotype-phenotype correlation, and should lead to the design of improved drugs for ameliorating the suffering of patients.

Wilson’s disease: cranial MRI observations and clinical correlation

INTRODUCTION

Study of MRI changes may be useful in diagnosis, prognosis and better understanding of the pathophysiology of Wilson's disease (WD). We aimed to describe and correlate the MRI abnormalities of the brain with clinical features in WD.

METHODS

MRI evaluation was carried out in 100 patients (57 males, 43 females; mean age 19.3+/-8.9 years) using standard protocols. All but 18 patients were on de-coppering agents. Their history, clinical manifestations and scores for severity of disease were noted.

RESULTS

The mean duration of illness and treatment were 8.3+/-10.8 years and 7.5+/-7.1 years respectively. MRI of the brain was abnormal in all the 93 symptomatic patients. The most conspicuous observations were atrophy of the cerebrum (70%), brainstem (66%) and cerebellum (52%). Signal abnormalities were also noted: putamen (72%), caudate (61%), thalami (58%), midbrain (49%), pons (20%), cerebral white matter (25%), cortex (9%), medulla (12%) and cerebellum (10%). The characteristic T2-W globus pallidal hypointensity (34%), "Face of giant panda" sign (12%), T1-W striatal hyperintensity (6%), central pontine myelinosis (7%), and bright claustral sign (4%) were also detected. MRI changes correlated with disease severity scores (P<0.001) but did not correlate with the duration of illness.

CONCLUSION

MRI changes were universal but diverse and involved almost all the structures of the brain in symptomatic patients. A fair correlation between MRI observations and various clinical features provides an explanation for the protean manifestations of the disease.

Profound midbrain atrophy in patients with Wilson's disease and neurological symptoms?

Wilson's disease (WD) is characterized by impaired hepatic copper secretion and subsequent copper accumulation in many organs predominantly liver and brain, secondary to loss of function mutations in the copper transport protein ATP7B. If the disease is recognized too late or treatment is not adequate, brain copper accumulation leads to progressive neurodegeneration with a variety of clinical symptoms. The nigrostriatal dopaminergic system seems rather vulnerable. Midbrain atrophy, however, has not been recognized as one of the prime features of patients with WD. Here we report quantification of midbrain diameter in 41 patients with WD. Data were correlated to the severity of neurological symptoms and the integrity of dopaminergic neurons measured via dopamine transporter binding. For control, we measured midbrain diameter in 18 patients with no evidence for brainstem dysfunction and 5 patients with progressive supranuclear palsy (PSP). Patients with WD had a reduced midbrain diameter (15.5 +/- 0.4 mm) compared to controls (18.5 +/- 0.2 mm). WD patients without neurological symptoms had midbrain diameter that were not different from controls (18.0 +/- 0.3 mm), while patients with neurological symptoms showed midbrain atrophy similar to patients with PSP (14.4 +/- 0.3 mm versus 14.1 +/- 0.3). There was a strong and significant correlation between midbrain atrophy and the severity of neurological symptoms (r= -0.68, p < 0.001) while midbrain atrophy and dopamine transporter binding correlated significantly but was less pronounced (r=0.46, p < 0.001). In summary, we were able to show, that midbrain diameter is an easy to perform quantification of neurodegeneration induced by brain copper accumulation and that other structures than substantia nigra dopaminergic neurons seem to contribute to midbrain atrophy in WD.

Wilson disease

Wilson disease (WD) is an autosomal recessive inherited disorder of copper metabolism, resulting in pathological accumulation of copper in many organs and tissues. The hallmarks of the disease are the presence of liver disease, neurologic symptoms, and Kayser-Fleischer corneal rings. The leading neurologic symptoms in WD are dysathria, dyspraxia, ataxia, and Parkinsonian-like extrapyramidal signs. Changes in the basal ganglia in brain magnetic resonance imaging (MRI) are characteristic features of the disease. In presence of liver cirrhosis, some features may resemble hepatic encephalopathy. Symptoms and MRI abnormalities may be fully reversible on treatment with zinc or copper chelators. Improvement can be monitored by serial recording of brain-stem-evoked responses. The basic defect is an impaired trafficking of copper in hepatocytes. ATP7B is the gene product of the WD gene located on chromosome 13 and resides in hepatocytes in the trans-Golgi network, transporting copper into the secretory pathway for incorporation into apoceruloplasmin and excretion into the bile. While about 40% of patients preset with neurologic symptoms, little is known about the role of copper and ATP7B in the central nervous system. In some brain areas, like in the pineal gland, ATP7B is expressed and functionally active. Increasing evidence supports an important role for metals in neurobiology. Two proteins related to neurodegeneration are copper-binding proteins (1) the amyloid precursor protein (APP), a protein related to Alzheimer's disease, and (2) the Prion protein, related to Creutzfeldt-Jakob disease. A major source of free-radical production in the brain derives from copper. To prevent metal-mediated oxidative stress, cells have evolved complex metal transport systems. APP is a major regulator of neuronal copper homeostasis and has a copper-binding domain (CuBD). The surface location of this site, structural homology of CuBD to copper chaperones, and the role of APP in neuronal copper homeostasis are consistent with the CuBD acting as a neuronal metallotransporter. There are several copper-containing enzymes in the brain, like dopamine beta hydroxylase or Cu/Zn superoxide dismutase (SOD1). Their function may be altered because of copper overload. WD appears to be associated with a dopaminergic deficit. Mutations in the SOD1gene cause familial amyotrophic lateral sclerosis. Survival of transgenic mice with a mutant SOD1 which fails to incorporate Cu((2+)) in its active site was improved by copper depletion. Wilson disease (WD) is an autosomal recessive inherited disorder in which copper pathologically accumulates primarily within the liver and subsequently in the neurologic system and many other organs and tissues. Presence of liver disease, neurologic symptoms, and Kayser-Fleischer corneal rings are the hallmarks of the disease.