Effective Treatment of Neurological Symptoms with Normal Doses of Botulinum Neurotoxin in Wilson's Disease: Six Cases and Literature Review

Tackling the neurological manifestations in Wilson's disease - currently available treatment options

INTRODUCTION

Wilson's disease (WD) is a potentially treatable, inherited disorder resulting from impaired copper metabolism. Pathological copper accumulation causes a range of symptoms, most commonly hepatic and a wide spectrum of neurological symptoms including tremor, dystonia, chorea, parkinsonism, dysphagia, dysarthria, gait and posture disturbances. To reduce copper overload, anti-copper drugs are used that improve liver function and neurological symptoms in up to 85% of patients. However, in some WD patients, treatment introduction leads to neurological deterioration, and in others, neurological symptoms persist with no improvement or improvement only after several years of treatment, severely affecting the patient's quality of life.

AREAS COVERED

This review appraises the evidence on various pharmacological and non-pharmacological therapies, neurosurgical procedures and liver transplantation for the management of neurological WD symptoms. The authors also discuss the neurological symptoms of WD, causes of deterioration and present symptomatic treatment options.

EXPERT OPINION

Based on case and series reports, current recommendations and expert opinion, WD treatment is focused mainly on drugs leading to negative copper body metabolism (chelators or zinc salts) and copper-restricted diet. Treatment of WD neurological symptoms should follow general recommendations of symptomatic treatment. Patients should be always considered individually, especially in the case of severe, disabling neurological symptoms.

The Necessity of a Locally Active Antidote in the Clinical Practice of Botulinum Neurotoxin Therapy: Short Communication

Recently, it was demonstrated that copper complexes and 3,4-diaminopyridine can effectively reduce the activity of the botulinum neurotoxin light chain. The aim of the present study was to indicate that treatment with an antidote may have a major influence, not only on the extremely rare disease of botulism, but also on the much more frequently occurring side effects experienced during BoNT therapy. This was a retrospective chart review of patients who were regularly treated with BoNT for various indications. The percentage of patients with clinical signs of overdosing was determined. In patients with facial dystonia, double vision and ptosis occurred as side effects. In patients with cervical dystonia, neck weakness and dysphagia were observed as the most frequent side effects. In oromandibular and oropharyngeal dystonia, abnormal tongue movements and dysphagia occurred frequently. In writer’s cramp and mild post-stroke hand spasticity, severe paresis of the injected and non-injected finger muscles was observed. Additionally, in the BoNT treatment of pain syndromes (such as tension headaches or migraines), neck weakness may occur. Across all indications for clinical BoNT applications, clinical signs of BoNT overdosing may occur in up to 5% of the BoNT-treated patients. Therefore, the development of an antidote for BoNT overdoses would be very much appreciated and would have a major influence on the management of BoNT therapy.

Effects of High-Frequency Repetitive Transcranial Magnetic Stimulation on Upper Limb Dystonia in Patients With Wilson's Disease: A Randomized Controlled Trial

Background: Upper limb dystonia is a frequent complication of Wilson's disease (WD). It can lead to poor quality of life and disability. Currently, no effective treatment for it exists. Therefore, we carried out a clinical trial to determine whether high frequency repetitive transcranial magnetic stimulation (rTMS) on the primary motor cortex alleviates upper limb dystonia in WD patients.

Methods: This study was a single-center, double-blind, randomized clinical study, included 60 WD patients with upper limb dystonia from a research base of WD in Hefei, China. Participants were randomly divided into a treatment group (TG) and a control group (CG). The TG received rTMS at 10 Hz, while the CG received sham stimulation for 7 consecutive days. Participants were assessed at baseline, after the seventh treatment session, and at 2 and 4 weeks after the seventh treatment session. The primary outcomes included patients' objective muscle tension and stiffness as measured with the MyotonPRO device. The secondary results were scores on clinical scales assessing muscle spasm and motor symptoms, which included the Modified Ashworth Scale (MAS), Unified Wilson's Disease Rating Scale (UWDRS), Burke Fahn Marsden Scale (BFM), and the Activities of Daily Living (ADL) scale.

Results: The analysis revealed that after 10 Hz rTMS, muscle tension (P < 0.01) and stiffness (P < 0.01) as measured by the MyotonPRO device decreased significantly in the TG compared to the CG. Moreover, clinically relevant scale scores, including the MAS (P < 0.01), UWDRS (P < 0.01), BFM (P < 0.01), and ADL (P < 0.01) were also significantly reduced.

Conclusion: High-frequency rTMS over the primary motor cortex may be an effective complementary and alternative therapy to alleviating upper limb dystonia in WD patients.

Clinical Trial Registration:http://www.chictr.org.cn/, identifier: ChiCTR2100046258.