Paroxysmal kinesigenic dystonia after methylphenidate administration

Unprovoked Dystonic Reaction in a Child Taking Long-Term Methylphenidate

In this report, we discuss the case of a 9-year-old male with Attention Deficit Hyperactivity Disorder (ADHD) on long-term methylphenidate and guanfacine who experienced acute orofacial dystonia that resolved immediately with the administration of benztropine. Current literature describes various cases of methylphenidate-induced dystonia, but ours appears to be the first reported instance of spontaneous dystonia without a recent change in dose or medication change. This may suggest the possibility of methylphenidate-induced dystonia spontaneously occurring several years after initiation.

Dyskinesia in Treatment-Naive and Stimulant-Treated Children With ADHD

Objective: Stimulants are safe and effective medications for the treatment of ADHD. There are a number of case studies that report stimulant-induced dyskinesia. The aim of this study was to compare dyskinesia in a treated and a treatment-naive group of children with ADHD, and a healthy control group. Method: Children aged 6 to 18 years were involved in the study (n = 158). Diagnosis of ADHD was measured with the Mini International Neuropsychiatric Interview Kid (MINI Kid). Dyskinesia was assessed with the Abnormal Involuntary Movement Scale (AIMS). Results: Before methylphenidate administration, the treated ADHD group showed significantly higher AIMS total score than the control group (p = .001) and the treatment-naive ADHD group (p < .001). We found the same pattern 1.5 hr after methylphenidate administration. Conclusion: These results call attention that clinicians should take special care for the possible development of dyskinesia during the treatment of their ADHD patients with methylphenidate.

Clinical Features and Treatment in the Spectrum of Paroxysmal Dyskinesias: An Observational Study in South-West Castilla y Leon, Spain

BACKGROUND

Paroxysmal dyskinesias (PxD) are a group of heterogeneous disorders characterized by intermittent episodes of involuntary movements. PxD include paroxysmal kinesigenic (PKD), nonkinesigenic (PNK), and exercise-induced (PED) varieties.

OBJECTIVES

To define the phenotype of primary and secondary PxD forms.

METHODS

Twenty-two patients with PxD (9 men/13 women) were evaluated in two hospitals in south-west Castilla y Leon, Spain. Clinical features of the episodes, causes, family history, and response to treatment were collected.

RESULTS

Thirteen participants with primary PxD (6 men/7 women) and 9 with secondary PxD (3 men/6 women) were recruited. Nine patients belong to three nonrelated families (2 had PKD and 1 had PED). Mean age at onset in primary PKD cases was 10 years (range 5-23 years), earlier than in PNKD (24 years) and PED (20 years). Most primary PKD cases experienced daily episodes of duration <1 minute, which are more frequent and shorter attacks than in PNKD (1-2 per month, 5 minutes) and PED (1 per day, 15 minutes). The location of the involuntary movements varied widely; isolated dystonia was more common than mixed chorea and dystonia. All PKD patients who received antiepileptic treatment significantly improved. Levodopa and ketogenic diet proved to be effective in two patients with PED. Secondary forms presented a later mean age of onset (51 years). Six cases had PNKD, 1 had PKD, 1 both PNKD and PKD, and 1 had PED. Causes comprised vascular lesions, encephalitis, multiple sclerosis, peripheral trauma, endocrinopathies, and drugs such as selective serotonin reuptake inhibitors (SSRIs).

CONCLUSION

The knowledge of the clinical features and spectrum of causes related to PxD is crucial to avoid delays in diagnosis and treatment, or even a nonorganic disorder diagnosis.

Effect of Biperiden Treatment in Acute Orofacial and Extremity Dyskinesia With Methylphenidate Therapy

Methylphenidate is a stimulant drug commonly prescribed to individuals with attention-deficit/hyperactivity disorder. The suggested underlying mechanism of acute dyskinesias is dopaminergic transmission increase. We describe a 9-year-old boy with a diagnosis of attention-deficit/hyperactivity disorder admitted to emergency clinic with primarily orofacial and extremity dyskinesia after administration of a first dose of 18 mg OROS (osmotic [controlled] release oral) methylphenidate (Concerta). OROS methylphenidate was discontinued, and the patient's symptoms resolved within 20 minutes after injection of biperiden by intravenous route (0.04 mg/kg). We wish to emphasize that acute orofacial dyskinesia and extremity dyskinesia can be observed during methylphenidate therapy and that biperiden can be successfully used in the treatment of this unpleasant condition. To the best of our knowledge, this is the first report of the use of biperiden therapy in this condition. This case report highlights the importance for physicians of awareness of dyskinesia as a potential adverse effect of methylphenidate therapy and indicates benefit of biperiden therapy.

Paroxysmal Dyskinesias

Paroxysmal dyskinesias (PD) are hyperkinetic movement disorders where patients usually retain consciousness. Paroxysmal dyskinesias can be kinesigenic (PKD), nonkinesigenic (PNKD), and exercise induced (PED). These are usually differentiated from each other based on their phenotypic and genotypic characteristics. Genetic causes of PD are continuing to be discovered. Genes found to be involved in the pathogenesis of PD include MR-1, PRRT2, SLC2A1, and KCNMA1. The differential diagnosis is broad as PDs can mimic psychogenic events, seizure, or other movement disorders. This review also includes secondary causes of PDs, which can range from infections, metabolic, structural malformations to malignancies. Treatment is usually based on the correct identification of type of PD. PKD responds well to antiepileptic medications, whereas PNKD and PED respond to avoidance of triggers and exercise, respectively. In this article, we review the classification, clinical features, genetics, differential diagnosis, and management of PD.

Dystonia in Methylphenidate Withdrawal: A Case Report

Few studies have described movement disorders as withdrawal symptoms during psychostimulant detoxification. Although dystonia has been reported as an uncommon adverse effect of methylphenidate treatment, it has not been described in the context of methylphenidate withdrawal. We report a case of dystonia as the main withdrawal symptom in a methylphenidate-dependent adult participating in an inpatient methylphenidate detoxification program. Although movement disorders such as dystonia are very rare adverse effects of methylphenidate withdrawal, practitioners need to be alert to this risk in order to initiate appropriate treatment.

Paroxysmal movement disorders: An update

Paroxysmal movement disorders comprise both paroxysmal dyskinesia, characterized by attacks of dystonic and/or choreic movements, and episodic ataxia, defined by attacks of cerebellar ataxia. They may be primary (familial or sporadic) or secondary to an underlying cause. They can be classified according to their phenomenology (kinesigenic, non-kinesigenic or exercise-induced) or their genetic cause. The main genes involved in primary paroxysmal movement disorders include PRRT2, PNKD, SLC2A1, ATP1A3, GCH1, PARK2, ADCY5, CACNA1A and KCNA1. Many cases remain genetically undiagnosed, thereby suggesting that additional culprit genes remain to be discovered. The present report is a general overview that aims to help clinicians diagnose and treat patients with paroxysmal movement disorders.

Drug-induced movement disorders

INTRODUCTION

Drug-induced movement disorders (DIMDs) can be elicited by several kinds of pharmaceutical agents. The major groups of offending drugs include antidepressants, antipsychotics, antiepileptics, antimicrobials, antiarrhythmics, mood stabilisers and gastrointestinal drugs among others.

AREAS COVERED

This paper reviews literature covering each movement disorder induced by commercially available pharmaceuticals. Considering the magnitude of the topic, only the most prominent examples of offending agents were reported in each paragraph paying a special attention to the brief description of the pathomechanism and therapeutic options if available.

EXPERT OPINION

As the treatment of some DIMDs is quite challenging, a preventive approach is preferable. Accordingly, the use of the offending agents should be strictly limited to appropriate indications and they should be applied in as low doses and as short duration as the patient's condition allows. As most of DIMDs are related to an unspecific adverse action of medications in the basal ganglia and the cerebellum, future research should focus on better characterisation of the neurochemical profile of the affected functional systems, in addition to the development of drugs with higher selectivity and better side-effect profile.

Iatrogenic neurology

Iatrogenic disease is one of the most frequent causes of hospital admissions and constitutes a growing public health problem. The most common type of iatrogenic neurologic disease is pharmacologic, and the central and peripheral nervous systems are particularly vulnerable. Despite this, iatrogenic disease is generally overlooked as a differential diagnosis among neurologic patients. The clinical picture of pharmacologically mediated iatrogenic neurologic disease can range from mild to fatal. Common and uncommon forms of drug toxicity are comprehensively addressed in this chapter. While the majority of neurologic adverse effects are listed and referenced in the tables, the most relevant issues are further discussed in the text.

Acute dyskinetic reaction in a healthy toddler following methylphenidate ingestion

BACKGROUND

Acute dyskinetic or dystonic reactions are a long-recognized complication of medications that alter dopamine signaling. Most reactions occur following exposure to agents that block dopamine receptors (e.g., neuroleptics). However, agents that increase dopaminergic transmission (such as methylphenidate) can also trigger acute dyskinesias. This has been previously reported only in patients also taking dopamine antagonists or, less commonly, in children with developmental abnormalities.

CASE DESCRIPTION

The present report describes a previously healthy toddler who developed transient torticollis and orolingual dyskinesias following accidental exposure to methylphenidate. He had no preexisting movement disorder, central nervous system injury, or developmental abnormalities--in short, none of the previously reported risk factors for this side effect.

HYPOTHESIS AND CONCLUSIONS

The unique features of this case led to the hypothesis that developmental shifts in dopamine signaling were the basis for his particular sensitivity to methylphenidate. If confirmed, this hypothesis has implications for the treatment of common childhood attentional and behavioral disorders. The article includes a literature review of dyskinetic/dystonic reactions in children and the developmental regulation of dopamine metabolism.

Oxcarbazepine-responsive paroxysmal kinesigenic dyskinesia in Wilson disease

A 22-year-old man presented with a 2-year history of tremor of the upper limbs associated to behavioral disorders. A magnetic resonance imaging of the brain showed hyperintensity in the right frontoparietal region, basal ganglia, particularly in the caudate nucleus, midbrain, and pons in T2 sequences, fluid-attenuated inversion recovery, and diffusion. Serum ceruloplasmin levels were 4 mg/dL (range, 20-45 mg/dL), and 24-hour urine cooper excretion was increased up to 223 µg (10-40 µg/24 hours). Slit lamp examination demonstrated the presence of a Kayser-Fleischer ring and penicillamine treatment started. Four months later, he developed episodes of paroxysmal dystonic posturing of his left arm, which increased in frequency reaching 2 or 3 attacks per hour. They were triggered by voluntary movements and forced him to adopt an abnormal flexion of the left forearm over the left bicep and were preceded by a tightening sensation of the left forearm muscles. Episodes completely remitted with oxcarbazepine.

Methylphenidate treatment and dyskinesia in children with attention-deficit/hyperactivity disorder

OBJECTIVES

Case reports suggest a relationship between methylphenidate treatment and dyskinesia in attention-deficit/hyperactivity disorder (ADHD). The aim of the current study was (a) to investigate abnormal involuntary movements of children with ADHD before and after the administration of methylphenidate and (b) to investigate the effect of a provocative assessment method used to make latent dyskinesia visible, which is included in the Abnormal Involuntary Movement Scale (AIMS).

METHODS

Participants, aged 6-18, were recruited from a Child and Adolescent Psychiatric Hospital and Outpatient Clinic (Vadaskert Foundation), Budapest, Hungary. Using a structured diagnostic interview (Mini International Neuropsychiatric Interview Kid), 37 children were included in the ADHD group and 34 children in the control group. The AIMS was used to observe and score dyskinesia.

RESULTS

There was a significant difference between the baseline total AIMS score in the ADHD and the control groups, with the ADHD subjects evidencing substantially higher severity than controls. Provocation, as applied with the administration of the AIMS, significantly increased the AIMS total score in both groups. The administration of methylphenidate had no effect on the total score of the AIMS. In the ADHD group, we observed a significant negative relationship between the patients' age and the overall severity on the AIMS. In contrast, in the control group we detected a significant positive relationship between the patients' age and the overall severity on the AIMS before and no relationship after provocation.

CONCLUSIONS

Methylphenidate-treated children with ADHD had more dyskinesia than children in the control group. Dyskinesia did not worsen after a single dose of methylphenidate. Higher dyskinesia scores in the methylphenidate-treated younger age group warrant caution in the methylphenidate treatment of ADHD; however, further studies are needed to clarify the possible causal relationship between dyskinesia and methylphenidate treatment and/or age and/or the disease itself.

Attention deficit and hyperactivity disorder in people with epilepsy: diagnosis and implications to the treatment

The association between attention deficit and hyperactivity disorder (ADHD) and epilepsy can cause significant impact on the social life of affected individuals and their families. Clinical studies suggest that 30-40% of people with epilepsy also have ADHD. There are no studies which demonstrate that short or long-term treatment with methylphenidate increases the risk of seizures. Some studies attempt to relate drug interactions between methylphenidate and antiepileptic drugs, but adverse effects of methylphenidate have not been shown clearly. This review presents some neurobiological and physiopathogenic aspects, common to ADHD and epilepsy, from recent research studies, related to pharmacology, neuroimaging and electroencephalography. Possible risk of occurrence of seizures associated with the use of methylphenidate are also discussed.

Juvenile Huntington disease exacerbated by methylphenidate: case report

The authors describe the case of an 8-year-old boy, otherwise healthy, who presented with symptoms consistent with attention-deficit hyperactivity disorder (ADHD) and was started on a trial of methylphenidate. Within 4 weeks, he experienced a rapid decline in fine motor skills, with dysarthria, intention tremor, motor impersistence, and diffusely increased tone. Symptoms persisted despite cessation of methylphenidate. At that time, a paternal history of Huntington disease was disclosed. Molecular analysis revealed an expansion in CAG repeats to 75 copies, within the range characteristic of juvenile Huntington disease. This report raises the possibility that use of dopaminergic agonists in patients with a family history of Huntington disease may lead to clinical exacerbation of motor symptoms and/or unwitting diagnosis in an unprepared family.

Methylphenidate-induced orofacial and extremity dyskinesia

In this paper, we report the case of a 6(1/2)-year-old male patient diagnosed with attention-deficit/hyperactivity disorder (ADHD) who developed orofacial and extremity dyskinesias immediately after methylphenidate treatment. The episode lasted 5 hours, peaking in intensity 2 hours after the medication was administered before gradually subsiding. Five hours after the methylphenidate was administered, the child became extremely irritated and aggressive, which lasted approximately 2 hours. The patient's general intelligence (IQ) was measured to be below the normal range. The potential relationship between methylphenidate intake and the development of dyskinesia calls into question different mechanisms involving drug-receptor interaction or individual drug sensitivity related to a lower IQ. Our case report has practical implications for physicians by raising their awareness of dyskinesia as a potential side effect of methylphenidate treatment.

Paroxysmal kinesigenic dyskinesias

The paroxysmal dyskinesias (PxDs) are involuntary, intermittent movement disorders manifested by dystonia, chorea, athetosis, ballismus or any combination of these hyperkinetic disorders. Paroxysmal kinesigenic dyskinesia (PKD), one of the four main types of PxD, involves sudden attacks of dyskinesias induced by voluntary movements. PKD most commonly occurs sporadically or as an autosomal-dominant familial trait with variable penetrance. Many causes of secondary PKD are being recognized. The exact pathophysiology of the PxDs awaits further elucidation, although basal ganglia dysfunction appears to play a major role. Although the precise gene remains unknown, genetic linkage studies have isolated loci on chromosome 16, which colocalizes with the locus for familial infantile convulsions and paroxysmal choreoathetosis in some studies. The episodic nature of PKD and its relationship with other episodic diseases, such as epilepsy, migraine, and episodic ataxia, suggests channelopathy as a possible underlying etiology. PKD may remit spontaneously, but it also responds well to anticonvulsants as well as some other agents.

Isolated orofacial dyskinesia: a methylphenidate-induced movement disorder

We report a case of orofacial dyskinesia in a 6-year-old female with attention-deficit-hyperactivity disorder who received a low dose of methylphenidate. The orofacial dyskinesia appeared immediately and subsided rapidly on the same day in an "on-off" fashion and on 3 separate days when methylphenidate was taken. To our knowledge this particular side effect has not been described previously and might represent an unusual type of brain response or sensitivity.

Secondary paroxysmal dyskinesias

Paroxysmal dyskinesias (PxDs) are involuntary, episodic movements that include paroxysmal kinesigenic (PKD), paroxysmal nonkinesigenic (PNKD), and paroxysmal hypnogenic (PHD) varieties. Although most PxDs are primary (idiopathic or genetic), we found 17 of our 76 patients with PxD (22%) to have an identifiable cause for their PxD (10 men; mean age, 41.4 years). Causes included peripheral trauma (in three patients), vascular lesions (in four), central trauma (in four), kernicterus (in two), multiple sclerosis (in one), cytomegalovirus encephalitis (in one), meningovascular syphilis (in one), and migraine (in one). The latency from insult to symptom onset ranged from days (trauma) to 18 years (kernicterus), with a mean of 3 years. Nine patients had PNKD, two had PKD, five had mixed PKD/PNKD, and one had PHD. Hemidystonia was the most common expression of the paroxysmal movement disorder, present in 11 patients. Both of the patients with PKD had symptom durations of <5 minutes. Symptom duration ranged from 10 seconds to 15 days for PNKD and from 5 minutes to 45 minutes for mixed PKD/PNKD. There were no uniformly effective therapies, but anticonvulsant drugs, clonazepam, and botulinum toxin injections were the most beneficial. Awareness of the variable phenomenology and the spectrum of causes associated with secondary PxD will allow for more timely diagnosis and early intervention.

Acute paroxysmal dystonia induced by fluoxetine

We report a case of a 32-year-old woman who developed paroxysmal episodes of right hemidystonia 2 days after taking fluoxetine. The attacks subsided 2 days after fluoxetine was withdrawn and did not recur afterwards. To our knowledge, this is the first report of paroxysmal dystonia induced by fluoxetine.

A 16-year-old with episodic hemisdystonia

The paroxysmal dyskinesias are a subset of the hyperkinetic movement disorders characterized by their episodic nature. Classification based on precipitating factors is helpful in considering treatment and prognosis. The clinical similarities with partial seizures are discussed. An approach to differential diagnosis, diagnostic evaluation, and treatment options are presented.