Zinc sulphate therapy for Wilson's disease after acute deterioration during treatment with low-dose D-penicillamine

Combined dimercaptosuccinic acid and zinc treatment in neurological Wilson's disease patients with penicillamine-induced allergy or early neurological deterioration

The clinical data of safety and efficacy of a combined treatment with dimercaptosuccinic acid (DMSA) and Zinc with 2 years’ follow-up in 60 neurological Wilson’s disease (WD) patients was retrospectively analyzed. All the patients included in the present study were newly diagnosed and initialized with D-penicillamine (DPA) treatment but were found to have either neurological deterioration or allergy, and their treatment was switched to a combined treatment of DMSA and Zinc. Fifty-one patients (85%) had the neurological symptoms improved 1 and 2 years after treatment, 7 (11.67%) experienced a stable neurological condition, and 2 (3.33%) suffered deterioration of neurological symptoms. No early neurological deterioration was observed in all patients. Twenty-five percent patients experienced mild adverse reactions which did not require a discontinuation of the DMSA and Zinc treatment. Our study confirmed the safety and efficacy of the combined DMSA and Zinc therapy as an initial and probably long-term treatment in neurological WD patients.

Beyond Guam: the cyanobacteria/BMAA hypothesis of the cause of ALS and other neurodegenerative diseases

Excitement about neurogenetics in the last two decades has diverted attention from environmental causes of sporadic ALS. Fifty years ago endemic foci of ALS with a frequency one hundred times that in the rest of the world attracted attention since they offered the possibility of finding the cause for non-endemic ALS throughout the world. Research on Guam suggested that ALS, Parkinson's disease and dementia (the ALS/PDC complex) was due to a neurotoxic non-protein amino acid, beta-methylamino-L-alanine (BMAA), in the seeds of the cycad Cycas micronesica. Recent discoveries that found that BMAA is produced by symbiotic cyanobacteria within specialized roots of the cycads; that the concentration of protein-bound BMAA is up to a hundred-fold greater than free BMAA in the seeds and flour; that various animals forage on the seeds (flying foxes, pigs, deer), leading to biomagnification up the food chain in Guam; and that protein-bound BMAA occurs in the brains of Guamanians dying of ALS/PDC (average concentration 627 microg/g, 5 mM) but not in control brains have rekindled interest in BMAA as a possible trigger for Guamanian ALS/PDC. Perhaps most intriguing is the finding that BMAA is present in brain tissues of North American patients who had died of Alzheimer's disease (average concentration 95 microg/g, 0.8mM); this suggests a possible etiological role for BMAA in non-Guamanian neurodegenerative diseases. Cyanobacteria are ubiquitous throughout the world, so it is possible that all humans are exposed to low amounts of cyanobacterial BMAA, that protein-bound BMAA in human brains is a reservoir for chronic neurotoxicity, and that cyanobacterial BMAA is a major cause of progressive neurodegenerative diseases including ALS worldwide. Though Montine et al., using different HPLC method and assay techniques from those used by Cox and colleagues, were unable to reproduce the findings of Murch et al., Mash and colleagues using the original techniques of Murch et al. have recently confirmed the presence of protein-bound BMAA in the brains of North American patients dying with ALS and Alzheimer's disease (concentrations >100 microg/g) but not in the brains of non-neurological controls or Huntington's disease. We hypothesize that individuals who develop neurodegenerations may have a genetic susceptibility because of inability to prevent BMAA accumulation in brain proteins and that the particular pattern of neurodegeneration that develops depends on the polygenic background of the individual.

Possible therapy for ALS based on the cyanobacteria/BMAA hypothesis

Although the cyanobacteria/BMAA hypothesis of the cause of ALS and other age-related neurodegenerative diseases remains to be proven, it is not too early to ask whether treatment would be possible if the hypothesis were correct. This paper reviews the possible ways that chronic BMAA neurotoxicity could be prevented or treated.

Withdrawal of penicillamine from zinc sulphate–penicillamine maintenance therapy in Wilson's disease: Promising, safe and cheap

BACKGROUND

Penicillamine, once considered the cornerstone of treatment for Wilson disease (WD), is rather expensive and toxic, and often causes neurological worsening. Zinc sulphate, aiming at the treatment of free-copper toxicosis, has emerged as effective, safe and cheap alternative.

AIM

To assess the effect of withdrawal of penicillamine from maintenance treatment with penicillamine and zinc sulphate.

PATIENTS AND METHODS

45 patients of WD (M:F: 28:17; age at diagnosis: 13.5+/-63 years), on both penicillamine (P) and zinc sulphate (Zn), couldn't continue penicillamine due to financial constraints. Their clinical data, disability and impairment scores (Schwab and England (S&E) score, Neurological Symptom Score (NSS), and Chu staging) and follow-up data of patients maintained only on zinc sulphate were recorded.

RESULTS

Majority of patients (84.4%) had neuropsychiatric manifestations. The mean duration of treatment with penicillamine (P) and zinc sulphate (P+Zn), before stopping penicillamine, was 107.4+/-67.3 months. 40 patients improved variably, while the rest didn't. They received only zinc sulphate for 27.2+/-8.5 months (range: 12 to 34) and 44 patients (97.7%) remained status quo or improved marginally. Only one patient reported worsening in dysarthria. Their disability and impairment scores during combination (penicillamine and zinc sulphate) and Zn alone were: Chu (1.3+/-0.5 vs. 1.5+/-1.9; p=0.4), NSS (1.8+/-3.1 vs. 1.5+/-2.3; p=0.03) and S&E (96.4+/-5.6 vs. 98.6+/-3.5; p=0.03). There were no adverse effects.

CONCLUSIONS

Withdrawal of penicillamine from zinc sulphate/penicillamine maintenance therapy for patients with Wilson's disease was effective, safe and economic, for almost all patients. This retrospective study reiterates that zinc sulphate may be used as a preferred mode of treatment for patients with Wilson's disease.

Zinc acetate treatment in Wilson's disease

OBJECTIVE

To briefly review the pathophysiology and diagnosis of Wilson's disease, and to evaluate the pharmacology, pharmacokinetics, clinical utility, adverse effects, dosing regimens, and pharmacoeconomics of zinc acetate therapy in Wilson's disease.

DATA SOURCES

A MEDLINE search (December 1966-December 1996) of the English-language literature using the terms zinc and Wilson's disease was conducted to identify pertinent clinical trials, review articles, and case reports. Additional articles were selected from bibliographies of the reviewed literature.

STUDY SELECTION AND DATA EXTRACTION

Due to the rarity of the disease, all articles were considered for possible inclusion in this review. Single case reports are referenced, but were not selected for evaluation.

DATA SYNTHESIS

Wilson's disease, an inherited disorder of copper metabolism, is fatal if untreated. The chelating drugs penicillamine and trientine have been the mainstay of therapy; however, adverse reactions of chelators often interfere with successful treatment. Recently, zinc acetate was approved in the US for maintenance therapy in patients initially treated with a chelating agent. Although studies evaluating large populations are lacking zinc therapy has demonstrated exceptional safety and efficacy over a period of 40 years. Zinc acetate can be used during pregnancy and for the treatment of presymptomatic patients, although data do not support its use as monotherapy in patients with acute neurologic or hepatic disease.

CONCLUSIONS

Zinc acetate is an effective maintenance therapy for patients with Wilson's disease. Negligible toxicity, compared with that of previously approved treatments, is a major advantage.

Acanthosis nigricans associated with hepatolenticular degeneration

Acanthosis nigricans and hepatolenticular degeneration (Wilson's disease) developed simultaneously in a 16-year-old boy. The diagnosis of Wilson's disease was based on the clinical presentation, including Kayser-Fleischer ring, hypoceruloplasminemia, hypocupremia, and hypercupriuria. His skin lesions were characterized by thick, dark brown, verrucous plaques on the dorsa of both feet, the neck, axillae, and groin. The histological findings were compatible with acanthosis nigricans. Six months after treatment with D-penicillamine, two grams per day, his skin lesions and neurological symptoms were much improved and no complications were observed.

Wilson's disease: resolution of MRI lesions following long-term oral zinc therapy

A 28-year-old man with Wilson's disease developed neurological deterioration after a low-dose of d-penicillamine treatment for 2 weeks. He showed an akinetic rigid syndrome with generalized dystonia. Brain magnetic resonance images (MRI) on T2 and proton weighted images showed an increased signal intensity over the thalamus, basal ganglia and brainstem, especially the midbrain and pons. After treatment had been changed to zinc sulphate, the akinetic-rigid syndrome and dystonia were improved slowly in the following 4 years. Serial MRI studies showed a gradual resolution of the lesions. His current neurological status was almost normal except for dysarthria and mild intention tremor.

Expression of androgen receptor in X-linked spinal and bulbar muscular atrophy and amyotrophic lateral sclerosis

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Wilson's disease: neurological and magnetic resonance imaging improvement on zinc treatment

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Wilson's disease with cerebral manifestation: monitoring therapy by CSF copper concentration

The clinical courses, cerebrospinal fluid (CSF) and serum copper concentrations and urinary copper excretions under different schemes of drug treatment in four patients with cerebral manifestations of Wilson's disease were monitored over 6-11 years. CSF copper concentration measurements were performed from the beginning of therapy onwards in three patients and from 16 months after initial treatment onwards in the fourth. CSF copper levels decreased slowly over the years in parallel with clinical improvements, and increased in one patient who interrupted therapy for 2 years. These findings confirm our hypothesis that the concentration of copper in the CSF is a valuable quantitative parameter reflecting the normalization of copper in the brain. Copper measurements during phases of initial neurological deterioration in two patients receiving D-penicillamine, and in one patient receiving D-penicillamine and zinc sulphate, revealed decreased free serum copper and CSF copper levels.