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

Magnetic Field Dependence of Spectral Correlations between 31P-Containing Metabolites in Brain

Spectral correlations between metabolites in ³¹P magnetic resonance spectroscopy (MRS) spectra of human brain were compared at 3 and 7 Tesla, the two commonly used magnetic field strengths for clinical research. It was found that at both field strengths, there are significant correlations between ³¹P-containing metabolites arising from spectral overlap, and their downfield correlations are markedly altered by the background spectral baseline. Overall, the spectral correlations between ³¹P-containing metabolites are markedly reduced at 7 Tesla with the increased chemical shift dispersion and the decreased membrane phospholipid signal. The findings provide the quantitative landscape of pre-existing correlations in ³¹P MRS spectra due to overlapping signals. Detailed procedures for quantifying the pre-existing correlations between ³¹P-containing metabolites are presented to facilitate incorporation of spectral correlations into statistical modeling in clinical correlation studies.

Wilson's disease update: An Indian perspective

Wilson's disease (WD) is an autosomal recessive disorder due to ATP7B gene mutation, resulting in defective copper metabolism, with liver and brain being primarily affected. Being a treatable disorder, early diagnosis and proper management of WD may result in near complete recovery. It has received significant attention over the past 50 years, with several Indian contributions. This study collates published Indian studies on WD in Pubmed and Embase databases and puts them in perspective. Several Indian case series suggest that WD may be more prevalent than thought. Commonly detected ATP7B mutation in India is p.C271X. Although initial Indian series reported significant osseomuscular presentation, neuropsychiatric and hepatic manifestations dominated the later reports. A significant male predominance is observed in Indian series. Pure hepatic presentation starts earlier than neurological or osseomuscular WD. A positive family history may be seen in nearly 50% of Indian WD cases with a high rate of consanguinity. Up to two-third of Indian cases may be initially misdiagnosed, with a mean diagnostic delay of up to 2 years. Abnormalities in serum ceruloplasmin and 24-hour urinary copper has been reported in more than four-fifth cases. Brain MRI is abnormal in nearly all neurological WD cases. Copper chelation remains the mainstay of therapy, with D-penicillamine being the most widely used chelator in India. Global Assessment Scale for WD is a comprehensive tool for clinical monitoring. Hepatic presentation carries a five-time higher mortality risk than neurological, with up to 90% Indian neurological WD cases recovering to pre-morbid functionality with adequate therapy.

[Phosphorus (P) magnetic resonance spectroscopy for evaluation of brain tissue metabolism and measuring non-invasive pH. A study involving 23 volunteers. Part I]

Evaluation of brain metabolism is an important part in examination of brain lesions. Phosphorus magnetic resonance spectroscopy opens up great opportunities for studying the energy metabolism and allows noninvasive examination of metabolic processes occurring both in healthy and in pathologic brain tissue by obtaining a spectrum of phosphorus-containing metabolites involved in the turnover of cell membrane phospholipids. The technique presented in this paper was used to conduct ³¹P MR spectroscopy and to estimate the ratio between the peaks of the main metabolites and intracellular pH of the healthy brain tissue of 23 volunteers in the age group under 30 years old in clinical settings. Based on the recorded stable phosphorus spectra of metabolites of the healthy brain tissue, the value of intracellular pH (6.963±0.044) and the ratio of the main PME/PDE peaks (1.17±0.20) were calculated. The database was created to subsequently analyze the metabolic changes in brain tissue spectra in norm and in pathology, as well as the intracellular pH variations that have diagnostic and prognostic value.

Predictors of seizure in Wilson disease: A clinico-radiological and biomarkers study

BACKGROUND

There is paucity of studies on predictors of seizures in Wilson disease with neurological manifestation (WDNM), and none has evaluated the role of copper (Cu) induced oxidative stress, proinflammatory and excitotoxicity in the genesis of seizure.

OBJECTIVES

To report frequency, refractoriness, and outcome of seizure in WDNM. We also evaluate role of Cu induced oxidative stress, excitotoxicity and cytokines in predicting seizures.

METHODS

The diagnosis of WDNM was based on clinical, MRI, KF ring and 24 h urinary Cu. Detailed clinical examination including severity of WD, occurrence of seizure, seizure semiology, antiepileptic drug (AED) and breakthrough seizures were noted. Cranial MRI and electroencephalography findings were noted. Serum free-Cu, oxidative stress markers (glutathione, total antioxidant capacity, malondialdehyde), glutamate and cytokines (interleukin 6, 8 and 10 and tumour necrosis factor α) were measured by atomic absorption spectrophotometer, spectrophotometer, fluorometer and flow cytometer respectively, and correlated with seizures. Patients were treated with zinc with or without penicillamine, and those with epilepsy received second-generation antiepileptic drugs (AEDs).

RESULTS

Out of 110 patients with WDNM, 16(14.5%) had seizures; focal in 11(68.7%) and generalized in 5(31.3%). Patients with seizure had higher serum free-Cu (35.87 ± 1.34 vs 31.72 ± 0.68; P = 0.02), severe dystonia (P = 0.04), and more frequent cortical (100% vs 6.4%; P < 0.01) and subcortical (81.3% vs 20.2%; P < 0.01) lesions on MRI compared to those without seizure. Oxidative stress markers (glutathione, total antioxidant capacity, malondialdehyde), cytokines and glutamate were elevated in WDNM compared to controls. On multivariate logistic regression analysis, cortical involvement (OR = 105.49; 95%CI = 8.74-1272.39; P < 0.01) and number of MRI lesions (OR = 1.99; 95% CI = 1.11-3.57; P = 0.02) were independent predictors of seizure. The seizures were controlled with single and dual AEDs in seven patients each, and two patients needed three AEDs. All the patients had seizure remission for a median follow up of 66(24-180) months.

CONCLUSION

About one-sixth WDNM patients have seizures especially in those with cortical and extensive MRI lesions. Seizures are easily controlled by AEDs.

Wilson disease: neurologic features

Wilson disease (WD) is a neurodegenerative disorder, which presents as a spectrum of neurologic manifestations that includes tremor, bradykinesia, rigidity, dystonia, chorea, dysarthria, and dysphagia, together with a combination of neurologic symptoms that can easily lead to misdiagnosis. An early diagnosis of WD, and appropriate anticopper treatment, usually leads to a marked improvement in patient health. Conversely, delayed diagnosis can result in persistent pathology, which, left untreated, can ultimately prove lethal. The aim of this chapter is to present a detailed description of the neurologic features of WD, including their evaluation, together with relevant ophthalmologic examinations, brain neuroimaging, and other laboratory measurements that show the extent of the involvement of the nervous system.

Inherited copper transport disorders: biochemical mechanisms, diagnosis, and treatment

Copper is an essential trace element required by all living organisms. Excess amounts of copper, however, results in cellular damage. Disruptions to normal copper homeostasis are hallmarks of three genetic disorders: Menkes disease, occipital horn syndrome, and Wilson's disease. Menkes disease and occipital horn syndrome are characterized by copper deficiency. Typical features of Menkes disease result from low copper-dependent enzyme activity. Standard treatment involves parenteral administration of copper-histidine. If treatment is initiated before 2 months of age, neurodegeneration can be prevented, while delayed treatment is utterly ineffective. Thus, neonatal mass screening should be implemented. Meanwhile, connective tissue disorders cannot be improved by copper-histidine treatment. Combination therapy with copper-histidine injections and oral administration of disulfiram is being investigated. Occipital horn syndrome characterized by connective tissue abnormalities is the mildest form of Menkes disease. Treatment has not been conducted for this syndrome. Wilson's disease is characterized by copper toxicity that typically affects the hepatic and nervous systems severely. Various other symptoms are observed as well, yet its early diagnosis is sometimes difficult. Chelating agents and zinc are effective treatments, but are inefficient in most patients with fulminant hepatic failure. In addition, some patients with neurological Wilson's disease worsen or show poor response to chelating agents. Since early treatment is critical, a screening system for Wilson's disease should be implemented in infants. Patients with Wilson's disease may be at risk of developing hepatocellular carcinoma. Understanding the link between Wilson's disease and hepatocellular carcinoma will be beneficial for disease treatment and prevention.