Natural History of "Pure" Primary Lateral Sclerosis

OBJECTIVE

To assess whether primary lateral sclerosis (PLS), classified as pure when the EMG is normal, converts to amyotrophic lateral sclerosis (ALS) after longitudinal follow-up.

METHODS

Retrospective chart review was performed of patients with pure PLS at Mayo Clinic in Rochester, MN (1990-2016). Inclusion criteria required a normal EMG during the first 4 years of symptoms.

RESULTS

Forty-three patients had pure PLS (25 female, 58%) with a median onset age of 50 years (range 38-78 years) and median follow-up at 9 years' disease duration (range 4-36 years). The ascending paraparesis phenotype (n = 30, 70%) was most common, followed by hemiparetic onset (n = 9, 21%) and bulbar onset (n = 4, 9%). Among the 30 paraparetic-onset cases, bladder symptoms (n = 18, 60%) and dysarthria (n = 15, 50%) were more common than pseudobulbar affect (n = 9, 30%) and dysphagia (n = 8, 27%). By the last follow-up, 17 of 30 (56%) used a cane and 6 (20%) required a wheelchair. The paraparetic variant, compared with hemiparetic and bulbar onset, had the youngest onset (48 vs 56 vs 60 years, respectively; p = 0.02). Five patients died; 1 patient required a feeding tube; and none required permanent noninvasive ventilation. Two patients developed an idiopathic multisystem neurodegenerative disorder, which surfaced after 19 and 20 years. Two patients developed minor EMG abnormalities. The remainder 39 had persistently normal EMGs.

CONCLUSIONS

Pure PLS did not convert to ALS after a median of 9 years' disease duration follow-up in our study population. The ascending paraparetic phenotype was most common, with earlier onset and frequent bladder involvement. After years of pure PLS, <5% develop a more pervasive neurodegenerative disorder.

Paraneoplastic neurological syndrome: an evolving story

Paraneoplastic neurological syndrome (PNS) comprises a group of neurological disorders that result from a misguided immune response to the nervous system triggered by a distant tumor. These disorders frequently manifest before the diagnosis of the underlying neoplasm. Since the first reported case in 1888 by Oppenheim, the knowledge in this area has evolved rapidly. Several classic PNS have been described, such as limbic encephalitis, paraneoplastic cerebellar degeneration, encephalomyelitis, opsoclonus-myoclonus, sensory neuronopathy, Lambert-Eaton Myasthenic syndrome, and chronic gastrointestinal dysmotility. It is now recognized that PNS can have varied nonclassical manifestations that extend beyond the traditional syndromic descriptions. Multiple onconeural antibodies with high specificity for certain tumor types and neurological phenotypes have been discovered over the past 3 decades. Increasing use of immune checkpoint inhibitors (ICIs) has led to increased recognition of neurologic ICI-related adverse events. Some of these resemble PNS. In this article, we review the clinical, oncologic, and immunopathogenic associations of PNS.

Tics and Tourette's syndrome

Tics and Tourette's syndrome are common hyperkinetic movement disorders seen mostly in the pediatric age group. Tics are defined as sudden, rapid, recurrent, nonrhythmic motor movements or vocalization, generally preceded by urge. Tourette's syndrome is defined as the presence of both motor and phonic tics for more than 1 year in patients with onset less than 18 years old. Most of these hyperkinetic movement disorders improve in adulthood. This review emphasizes the clinical pearls in the diagnosis and distinguishing it from other movement disorders. The treatment ranges from behavioral therapies, medical management, and also surgical treatment such as deep brain stimulation that is limited to refractory patients.

Spectrum of Movement Disorders in Patients With Neuroinvasive West Nile Virus Infection

Background

West Nile virus (WNV) is a flavivirus that is recognized as one of the common causes of arboviral neurological disease in the world. WNV infections usually manifest with constitutional symptoms such as fever, fatigue, myalgia, rash, arthralgia, and headache. Neuroinvasive WNV infections are characterized by signs and symptoms suggestive of meningitis, encephalitis, meningoencephalitis, and acute flaccid paralysis. In addition, many patients with neuroinvasive WNV infection develop a wide range of movement disorders. This article aims to comprehensively review the spectrum and natural course of the movement disorders observed in patients with neuroinvasive WNV infections.

Methods

A literature search was performed in March 2019 (in PubMed and EMBASE) to identify articles for this review.

Results

Movement disorders observed in the context of WNV infections include tremor, opsoclonus-myoclonus, parkinsonism, myoclonus, ataxia, and chorea. Most often, these movement disorders resolve within a few weeks to months with an indolent course. The commonly observed tremor phenotypes include action tremor of the upper extremities (bilateral > unilateral). Tremor in patients with West Nile meningitis subsides earlier than that in patients with West Nile encephalitis/acute flaccid paralysis. Opsoclonus-myoclonus in WNV infections responds well to intravenous immunoglobulins/plasmapheresis/corticosteroids. Parkinsonism has been reported to be mild in nature and usually lasts for a few weeks to months in the majority of the patients.

Conclusion

A wide spectrum of movement disorders is observed in neuroinvasive WNV infections. Longitudinal studies are warranted to obtain better insights into the natural course of these movement disorders.

Botulinum Toxin in Restless Legs Syndrome-A Randomized Double-Blind Placebo-Controlled Crossover Study

Background: Restless Legs Syndrome (RLS) is a common movement disorder with an estimated prevalence of up to 12%. Previous small studies with onabotulinumtoxin A (OnaA) for RLS have shown inconsistent results. Methods: Twenty-four patients with an International RLS score (IRLS) of >11 (moderate-severe) were enrolled in this blinded, placebo-controlled crossover study. Twenty-one patients completed the evaluations at 4, 6, and 8 weeks after each injection. One-hundred units of Incobotulinumtoxin A (IncoA) or normal saline were injected into tibialis anterior, gastrocnemius, and biceps femoris muscles each side. Results: Improvement from a severe (IRLS >21) to a mild/moderate (IRLS ≤20) score was significant at four weeks (p = 0.0036) and six weeks (p = 0.0325) following IncoA administration compared to placebo. Additionally, there was significant improvement in pain score at six weeks as measured by Visual Analogue Scale (p = 0.04) and the Johns Hopkins Quality of Life Questionnaire (p = 0.01) in the IncoA group. Definite or marked improvement on Patient Global Impression of Change was seen in 7 out of 21 patients in the IncoA group vs. 1 out of 21 patients in the placebo group at 4 weeks (p = 0.012). Conclusion: IncoA injection lead to a reduction in severity of RLS symptoms, pain score, and quality of life, without any adverse effects.

Botulinum toxin in essential hand tremor - A randomized double-blind placebo-controlled study with customized injection approach

INTRODUCTION

To evaluate the safety and efficacy of incobotulinumtoxinA (IncoA) injection for treatment of essential hand tremor. In essential tremor and Parkinson's disease tremor, administration of onabotulinumtoxinA via a fixed injection approach improves the tremor but a high percentage of patients (30-70%) develop moderate to severe hand weakness which has limited its use in clinical practice.

METHODS

This study was performed from July 2013 to July 2016 on 33 subjects. This is a double-blind, placebo-controlled, crossover trial injecting 80-120 units of IncoA into 8-14 hand and forearm muscles using a customized approach. The subjects were followed for 28 weeks. The treatment efficacy was evaluated by the Fahn Tolosa Marin tremor rating score and NIH genetic criteria for tremor severity at 4 and 8 weeks after each of the two sets of treatments. Hand strength was assessed by an ergometer.

RESULTS

There was statistically significant improvement in clinical rating score of tremor at 4 and 8 weeks following the IncoA injection.

CONCLUSION

In this study, injection of IncoA treatment via a customized approach improved essential tremor on the clinical scales and patient's perception with a low occurrence of significant hand weakness.

Botulinum Toxin in Parkinson Disease Tremor: A Randomized, Double-Blind, Placebo-Controlled Study With a Customized Injection Approach

BACKGROUND

In essential tremor and Parkinson disease (PD) tremor, administration of onabotulinumtoxinA via a fixed injection approach improves the tremor, but many patients (30%-70%) develop moderate to severe hand weakness, limiting the use of onabotulinumtoxinA in clinical practice.

OBJECTIVE

To evaluate the safety and efficacy of incobotulinumtoxinA (IncoA) injection for the treatment of tremor in PD.

PATIENTS AND METHODS

In this double-blind, placebo-controlled, crossover trial, 30 patients each received 7 to 12 (mean, 9) IncoA injections into hand and forearm muscles using a customized approach. The study was performed from June 1, 2012, through June 30, 2015, and participants were followed for 24 weeks. Treatment efficacy was evaluated by the tremor subsets of the Unified Parkinson's Disease Rating Scale and the Patient Global Impression of Change 4 and 8 weeks after each of the 2 sets of treatments. Hand strength was assessed using an ergometer.

RESULTS

There was a statistically significant improvement in clinical rating scores of rest tremor and tremor severity 4 and 8 weeks after the IncoA injection and of action/postural tremor at 8 weeks. There was a significant improvement in patient perception of improvement at 4 and 8 weeks in the IncoA group. There was no statistically significant difference in grip strength at 4 weeks between the 2 groups.

CONCLUSION

Injection of IncoA via a customized approach improved PD tremor on a clinical scale and patient perception, with a low occurrence of significant hand weakness.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT02419313.

Botulinum Toxin Treatment of Neuropathic Pain

Neuropathic pain (NP), a common form of human pain, often poorly responds to analgesic medications. In this review the authors discuss the pathophysiology and conventional treatment of neuropathic pain and provide evidenced-based statements on the efficacy of botulinum neurotoxins (BoNTs) in this form of pain. The level of efficacy for BoNT treatment in each category of NP is defined according to the published guidelines of the American Academy of Neurology. The data indicate that BoNT treatment (most of the literature is with onabotulinumtoxinA) is effective (level A evidence) in postherpetic neuralgia and trigeminal neuralgia. It is probably effective (level B) in posttraumatic neuralgia and painful diabetic neuropathy. The data on complex regional pain syndrome, carpal tunnel syndrome, occipital neuralgia, and phantom limb pain are preliminary and await conduction of randomized, blinded clinical trials. Much remains to be learned about the most-effective dosage and technique of injection, optimum dilutions, and differences among BoNTs in the treatment of neuropathic pain.

Incobotulinum Toxin-A Improves Post-Surgical and Post-Radiation Pain in Cancer Patients

Cancer patients who undergo surgery or radiation can develop persistent focal pain at the site of radiation or surgery. Twelve patients who had surgery or radiation for local cancer and failed at least two analgesic medications for pain control were prospectively enrolled in a research protocol. Patients were injected up to 100 units of incobotulinum toxin A (IncoA) intramuscularly or subcutaneously depending on the type and location of pain (muscle cramp or neuropathic pain). Two patients passed away, one dropped out due to a skin reaction and another patient could not return for the follow up due to his poor general condition. All remaining 8 subjects (Age 31–70, 4 female) demonstrated significant improvement of Visual Analog Scale (VAS) (3 to 9 degrees, average 3.9 degrees) and reported significant satisfaction in Patients’ Global Impression of Change scale (PGIC) (7 out of 8 reported the pain as much improved). Three of the 8 patients reported significant improvement of quality of life.

Tremor and Klinefelter's Syndrome

Background

Klinefelter’s syndrome (KS) has been associated with tremor, but reports on tremor phenomenology and treatment are limited.

Case Reports

Patient 1 is a 17-year-old male with a dystonic tremor treated with deep brain stimulation (DBS). Patient 2 is a 57-year-old male with a predominant left hand resting tremor and dystonic features.

Discussion

Our cases suggest that the tremor in patients with KS may be dystonic in nature. Patient 1 is also the third reported case of successful treatment with DBS. These cases have implications for elucidating the underlying neurobiological mechanism of tremor and identifying treatment options.

Hypocupremia: a possible association with late cortical cerebellar atrophy

BACKGROUND

We report a patient, diagnosed with late cortical cerebellar atrophy, who had persistent low serum copper levels.

CASE REPORT

A 48-year-old male developed progressive difficulty with balance, frequent falls, and dysarthric speech, which worsened over a short time span. He had an extensive ataxia work-up, which was unremarkable except for persistent low serum copper levels despite adequate supplementation. Magnetic resonance imaging of the brain showed marked cerebellar atrophy. The patient experienced progressive worsening of symptoms, which did not improve with either oral or parenteral copper supplementation.

DISCUSSION

To our knowledge, ours is the first case report of late cortical cerebellar atrophy in the setting of low serum copper levels. The current report should trigger further research in mechanisms leading to copper deficiency and its possible role in cerebellar disease.

Bilateral gluteal dyskinesia: discussion of a rare movement disorder

BACKGROUND

Involuntary movements of gluteal muscles have rarely been reported.

CASE REPORT

This 46-year-old female with pelvic endometriosis developed involuntary rhythmic movements in the left gluteus maximus, which within a year became bilateral. The movements gradually increased in intensity and interfered with ambulation. Electromyography, at rest, demonstrated almost continuous periodic gluteal discharges, with left-sided discharges seeming to lead to those on the right. OnabotulinumtoxinA injections into the gluteal muscles improved the movements.

DISCUSSION

A rare and previously unreported form of gluteal involuntary movements with periodic electromyographic discharges is described. The cause is uncertain. The differential diagnosis of this unusual movement disorder is discussed, with the most likely diagnosis being myoclonus.