Paroxysmal choreoathetosis. Report of Chinese cases

Case Report: A Case of Concomitant Paroxysmal Kinesigenic Dyskinesia and Epilepsy: Can We Treat Two Birds With One Stone?

Background

Paroxysmal kinesigenic dyskinesia (PKD) is characterized by recurrent episodes of movement-induced motor attacks. PKD patients may have concomitant epilepsy. Differentiation between the two disorders and effective control of both diseases remain challenging.

Case Presentation

We present a Chinese girl with typical manifestations of PKD, who also suffered from generalized tonic-clonic seizure attacks at the same time. Genetic testing confirmed a PRRT2 mutation (c.649dupC). Oxcarbazepine was initially used, but withdrawn due to a hypersensitivity reaction. Levetiracetam was initiated afterwards, which was effective for seizures but failed to control her PKD symptoms. The addition of lacosamide (LCM) completely controlled her PKD symptoms.

Conclusion

This is the first case reporting the effectiveness of LCM for concomitant PKD and epilepsy. Our case proposes a novel alternative for such patients who are resistant or cannot tolerate conventional anti-sodium antiepileptics.

Idiopathic paroxysmal kinesigenic dyskinesia in Malaysia, a multi-racial Southeast Asian country

Paroxysmal kinesigenic dyskinesia is a rare disorder, and there are few reports of Asian patients with this condition. We reviewed the clinical features of all patients with idiopathic paroxysmal kinesigenic dyskinesia (PKD) seen at a major neurological centre in Malaysia. The charts of 11 patients with idiopathic PKD seen between 1995 and 2008 were reviewed retrospectively. The male:female ratio was 9:2. Ten patients were of Chinese ethnicity, and one was Malay. Three patients (from two families) had a family history of PKD. The involuntary movement was dystonia in 73% of patients. In one patient, attacks were precipitated by vestibular stimulation. One patient had generalized epilepsy. Another patient who did not have epilepsy demonstrated epileptiform discharges. Only slightly over one-quarter of patients had a positive family history. Males, and people of Chinese ancestry, seem to be affected more frequently by PKD in certain Asian populations.

Paroxysmal dyskinesias in childhood

We report on clinical features of a large series of patients with paroxysmal dyskinesias. Fourteen patients had paroxysmal kinesigenic dyskinesia, with a mean age at onset of 7.1 years. In thirteen children the condition was idiopathic and nine of them had a positive family history; the remaining one had a Chiari malformation. Response to antiepileptic drugs was good in 60% of the treated patients. Six children had paroxysmal non-kinesigenic dyskinesia, with a mean age at onset of 8.1 years. Five children were symptomatic because of cerebral palsy (two patients), basal ganglia stroke (one patient), and acute inflammatory encephalopathy (one patient); the remaining patient's condition was familial with autosomal-dominant mode of inheritance. Response to medical treatment was unsuccessful contrasting with paroxysmal kinesigenic dyskinesia. Six children had paroxysmal exercise-induced dyskinesia, with a mean age at onset of 5 years. Their condition was idiopathic, with a positive family history in four. Two of these patients had also rolandic epilepsy and writer's cramp, and the syndrome had been previously mapped to chromosome 16. Although there have been great advances in the genetics of paroxysmal dyskinesias in which an ion channel dysfunction has been hypothesized, the diagnosis is still based on clinical grounds. The precise classification of the patients with paroxysmal dyskinesias is important for therapeutic decisions.

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.

Early-onset absence epilepsy and paroxysmal dyskinesia

PURPOSE

To report on the association of childhood absence epilepsy and paroxysmal dyskinesia (PD).

METHODS

We describe six patients aged 6 to 27 years (mean, 14 years) who were identified in five centers participating in a European study group. Patients had been followed up clinically from the first symptoms and had been studied with video-EEG recordings of absence seizures, videotaping of dyskinetic attacks, and brain magnetic resonance imaging (MRI).

RESULTS

Four patients were sporadic, and two were siblings. Age at onset of absence seizures was unusually early (range, 3 months to 3 years 6 months; mean, 16 months), with four children having their first episodes within the first year of life, and the remaining two by age 3 years 6 months. Resistance to multiple appropriate drugs was seen in five children, in four of whom absences improved remarkably when ethosuximide was added. Absences remitted between age 8 and 13 years in the three patients in whom follow-up was long enough. Different types of PD were seen including paroxysmal kinesigenic dyskinesia (one patient), paroxysmal exercise-induced dystonia (three patients), and paroxysmal tonic upgaze (two siblings). In most patients, PD appeared at a later age than, co-occurred with, and outlasted absence seizures. Only in the two siblings with tonic upgaze, dyskinetic attacks had an earlier onset. PD improved with increasing age and did not usually produce severe disability.

CONCLUSIONS

There is a widening spectrum of epilepsy and PD syndromes, within which epilepsy has the characteristics of the common idiopathic syndromes, with some atypical features.

The genetics of primary dystonias and related disorders

Dystonias are a heterogeneous group of disorders which are known to have a strong inherited basis. This review details recent advances in our understanding of the genetic basis of dystonias, including the primary dystonias, the 'dystonia-plus' syndromes and heredodegenerative disorders. The review focuses particularly on clinical and genetic features and molecular mechanisms. Conditions discussed in detail include idiopathic torsion dystonia (DYT1), focal dystonias (DYT7) and mixed dystonias (DYT6 and DYT13), dopa-responsive dystonia, myoclonus dystonia, rapid-onset dystonia parkinsonism, Fahr disease, Aicardi-Goutieres syndrome, Hallervorden-Spatz syndrome, X-linked dystonia parkinsonism, deafness-dystonia syndrome, mitochondrial dystonias, neuroacanthocytosis and the paroxysmal dystonias/dyskinesias.

Idiopathic epilepsy and paroxysmal dyskinesia

Although some motor manifestations of epilepsy and of paroxysmal dyskinesia may be difficult to differentiate clinically, the current understanding is that the two disorders are clinically distinct. However, there are several recent reports of families in which different individuals had either disorder or both manifestations, with age-related expression. Co-occurrence makes it likely that a common, genetically determined, pathophysiologic abnormality is variably expressed in the cerebral cortex and in basal ganglia. A rather homogeneous syndrome of autosomal dominant infantile convulsions and paroxysmal (dystonic) choreoathetosis (ICCA) was described in six families from France, China and Japan. Linkage analysis in the French and Chinese families allowed the mapping of the disease gene in a 10-cM interval within the pericentromeric region of chromosome 16. An Italian pedigree in which three members in the same generation were affected by rolandic epilepsy, paroxysmal exercise-induced dystonia (PED), and writer's cramp was subsequently reported. Linkage analysis showed a common homozygous haplotype in a critical region spanning 6 cM and entirely included within the ICCA critical region. Clinical analogies and linkage findings suggest that the same gene could be responsible for rolandic epilepsy, PED, writer's cramp (WC), and ICCA, with specific mutations accounting for each of these mendelian disorders. Evidence for a major gene or a cluster of genes for epilepsy and paroxysmal dyskinesia to the pericentromeric region of chromosome 16 is reinforced by the recent linkage of a family with autosomal dominant paroxysmal dyskinesia to a critical region partially overlapping with ICCA and contiguous to the RE-PED-WC regions. Additional autosomal dominant pedigrees are on record, from Australia and Italy, in which epilepsy was variably associated with paroxysmal kinesigenic or exercise-induced dystonia. Ion channel genes are potentially interesting candidates for syndromes featuring both these paroxysmal neurologic disorders. Increased awareness of their possible co-occurrence will certainly increase the number of observations in the next few years.

Paroxysmal dystonia induced by exercise and acetazolamide

We report a case of a 40-year-old woman with dystonic attacks precipitated by slight exercise. Episodes lasted 2-5 min and were not precipitated by sudden movements or by being startled, drinking alcohol, coffee or tea, or by stress. Secondary dystonia was ruled out and brain magnetic resonance imaging (MRI) was unremarkable. Routine and video electroencephalogram (EEG) during and between attacks were normal. Acetazolamide greatly worsened her condition, whereas gabapentin [1-(aminomethyl) cyclohexaneacetic acid] treatment markedly reduced the frequency and severity of the episodes.

Paroxysmal kinesigenic choreoathetosis locus maps to chromosome 16p11.2-q12.1

Paroxysmal kinesigenic choreoathetosis (PKC), the most frequently described type of paroxysmal dyskinesia, is characterized by recurrent, brief attacks of involuntary movements induced by sudden voluntary movements. Some patients with PKC have a history of infantile afebrile convulsions with a favorable outcome. To localize the PKC locus, we performed genomewide linkage analysis on eight Japanese families with autosomal dominant PKC. Two-point linkage analysis provided a maximum LOD score of 10.27 (recombination fraction [theta] =.00; penetrance [p] =.7) at marker D16S3081, and a maximum multipoint LOD score for a subset of markers was calculated to be 11.51 (p = 0.8) at D16S3080. Haplotype analysis defined the disease locus within a region of approximately 12.4 cM between D16S3093 and D16S416. P1-derived artificial chromosome clones containing loci D16S3093 and D16S416 were mapped, by use of FISH, to 16p11.2 and 16q12.1, respectively. Thus, in the eight families studied, the chromosomal localization of the PKC critical region (PKCR) is 16p11.2-q12.1. The PKCR overlaps with a region responsible for "infantile convulsions and paroxysmal choreoathetosis" (MIM 602066), a recently recognized clinical entity with benign infantile convulsions and nonkinesigenic paroxysmal dyskinesias.

Autosomal recessive rolandic epilepsy with paroxysmal exercise-induced dystonia and writer's cramp: delineation of the syndrome and gene mapping to chromosome 16p12-11.2

We describe a pedigree in which 3 members in the same generation are affected by Rolandic epilepsy (RE), paroxysmal exercise-induced dystonia (PED), and writer's cramp (WC). Both the seizures and paroxysmal dystonia had a strong age-related expression that peaked during childhood, whereas the WC, also appearing in childhood, has been stable since diagnosis. Genome-wide linkage analysis performed under the assumption of recessive inheritance identified a common homozygous haplotype in a critical region spanning 6 cM between markers D16S3133 and D16S3131 on chromosome 16, cosegregating with the affected phenotype and producing a multipoint LOD score value of 3.68. Although its features are unique, this syndrome presents striking analogies with the autosomal dominant infantile convulsions and paroxysmal coreoathetosis (ICCA) syndrome, linked to a 10 cM region between D16S401 and D16S517, which entirely includes the 6 cM of the RE-PED-WC critical region. The same gene may be responsible for both RE-PED-WC and ICCA, with specific mutations explaining each of these Mendelian disorders. This report shows that idiopathic focal disorders such as epilepsy and dystonia, can be caused by the same genetic abnormality, may have a transient expression, and may be inherited as an autosomal recessive trait.

Clinical manifestations of 20 Taiwanese patients with paroxysmal kinesigenic dyskinesia

INTRODUCTION

We compared the clinical manifestations and response to medications between familial and sporadic patients with paroxysmal kinesigenic dyskinesia (PKD), and also between patients with autosomal dominant (AD) and autosomal recessive (AR) inheritance.

MATERIAL AND METHODS

This retrospective cohort study included 9 familial and 11 sporadic Taiwanese patients with PKD diagnosed during a 10-year period at one of two hospitals. The mean duration of follow-up was 3.8 +/- 2.7 years. Each patient was interviewed and their medical records, as well as videotape recordings of PKD attacks in 6 patients, were used for analysis. Patients were treated with either carbamazepine or phenytoin, and the efficacy of sodium valproate was tested in 5 patients.

RESULTS

No single distinguishing feature in terms of clinical manifestations or therapeutic response was found to differentiate among familial, and sporadic cases, or between AD and AR inheritance. Carbamazepine and phenytoin were superior to sodium valproate in treating both familial and sporadic PKD patients, and both drugs resulted in almost complete remission of attacks.

CONCLUSION

Our findings indicate that the sporadic and familiar forms of PKD, as well as the AR and AD inherited types, are similar in terms of clinical manifestations and response to treatment. The functional status and prognosis of our Taiwanese patients suggest that PKD is a relatively benign entity.

Paroxysmal kinesigenic choreoathetosis in Singapore and its relationship to epilepsy

OBJECTIVES

To study the clinical characteristics of paroxysmal kinesigenic choreoathetosis (PKC) in our local population and its relationship to epilepsy.

METHODS

We reviewed retrospectively 15 patients who were managed by neurologists in our department from 1982 to 1996. The literature was also reviewed to study the association between PKC and epilepsy.

RESULTS

In our study, all the cases were idiopathic. The male to female ratio was 14:1 with all major races represented. Sixty percent of our patients suffered dystonic posturing rather than chorea, during the attacks. Twenty-one percent had a family history of a similar disorder which appeared to be of autosomal dominant inheritance. The sporadic form (79%) predominated in Singapore. One had a history of febrile fits while two had a history of epilepsy. We reviewed the available literature and found five other patients with idiopathic PKC also suffering from epilepsy. Of the 83 patients reviewed, 8% had epilepsy. This further strengthens the relationship between the two conditions. All our patients responded well to phenytoin at doses between 100 and 400 mg/day.

CONCLUSION

PKC affected all three major races in our population with a high male to female ratio of 14:1. Seventy-nine percent of our cases were sporadic and 60% suffered dystonic posturing during attacks. Of the cases reviewed, 8% of patients with idiopathic PKC also had epilepsy.

Epilepsy or paroxysmal kinesigenic choreoathetosis?

Epileptic seizures induced by sudden movement and paroxysmal kinesigenic choreoathetosis (PKC) have often been confused in the past, owing to the close similarity of the attacks, the equally good response to anticonvulsants, and the frequent occurrence of epilepsy and PKC in the same family, or even in the same patient. The pathophysiology of PKC is still unclear and its relationship with epilepsy open to discussion. The sparing of consciousness and the lack of postictal phenomena are constant features of PKC, thus differentiating this syndrome from epilepsy. We report the case of an 8-year-old boy with frequent brief tonic attacks, without loss of consciousness, triggered by sudden movement. The neurologic examination, EEG and MRI did not help to differentiate between epilepsy and PKC. Only the occurrence of a longer seizure with clouding of consciousness and the recording of the postictal abnormalities on the EEG supported a diagnosis of reflex epilepsy induced by movement.

Paroxysmal dyskinesias: clinical features and classification

We studied 46 patients with paroxysmal dyskinesia and classified them according to phenomenology, duration of attacks, and etiology. There were 13 patients, 7 females, who had paroxysmal kinesigenic dyskinesia (PKD), 10 with attacks lasting 5 minutes or less (short lasting) and 3 with attacks lasting longer than 5 minutes (long lasting). Twenty-six patients, 18 females, had paroxysmal nonkinesigenic dyskinesia (PNKD), 9 with short-lasting and 17 with long-lasting PNKD. Five patients, 3 females, had paroxysmal exertion-induced dyskinesia (PED), 3 with short-lasting PED and the other 2 with long-lasting PED. In addition, there was 1 patient with paroxysmal hypnogenic dyskinesia (PHD) and 1 with paroxysmal superior oblique myokymia. Only 2 patients, 1 with PKD and 1 with PHD, had family history of paroxysmal dyskinesias. No specific cause could be identified in 21 patients; in the other 23 patients the etiologies included the following: psychogenic (9 patients), cerebrovascular diseases (4), multiple sclerosis (2), encephalitis (2), cerebral trauma (2), peripheral trauma (2), migraine (1), and kernicterus (1). Nine of 10 (90%) patients with PKD improved with medications, mostly anticonvulsants, compared with only 7 of 19 (37%) with PNKD. This new classification, based chiefly on precipitating events, allowed appropriate categorization of the attacks in all our patients with paroxysmal dyskinesias.

Paroxysmal kinesigenic choreoathetosis with abnormal electroencephalogram during attacks

An 18-year-old man with paroxysmal kinesigenic choreoathetosis (PKC) showed rhythmic electroencephalographic (EEG) discharges of 5-Hz spikes over the entire scalp during episodes. The EEG findings in this case suggest that PKC may have an epileptogenic basis.

Typical and atypical forms of paroxysmal choreoathetosis

Two children with clinical pictures of paroxysmal kinesinogenic choreoathetosis and paroxysmal dystonic choreoathetosis are described and compared with previous reports with regard to diagnostic procedures, therapeutic approach and prognosis. A third case, characterized by paroxysmal dyskinesia induced by exercise and associated with choreiform nonprogressive signs, is also described. Such an association has not been reported previously. This unusual clinical picture indicates the possibility of intermediate forms in the paroxysmal choreoathetosis group and suggests a relationship between paroxysmal motor disorders and benign familial chorea with early onset.

Acquired paroxysmal movement disorders

Acquired paroxysmal movement disorders are reported less frequently than the familial forms of paroxysmal dyskinesias. Three children, with the acquired form of the disorder which followed an early childhood encephalopathic event, are described. Three similarly affected children have been reported previously. Movement disorders developing after perinatal encephalopathy appear to be a distinct entity. Patients with this condition demonstrated clinical improvement following the initiation of antiepileptic medications.

Familial paroxysmal dystonia induced by exercise

A mother and daughter are described with paroxysmal dystonia induced by exercise. As has been reported in one previous family, the attacks were provoked in the lower limbs by prolonged exertion but not by sudden movements. It was also found that involuntary movements could be induced focally in any limb either by local exercise or by sensory stimulation restricted to that limb.

Autosomal dominant paroxysmal kinesigenic choreoathetosis. An electroneurophysiological study

A case of an 11-year-old boy with an autosomal dominant form of paroxysmal kinesigenic choreoathetosis is presented. Routine EEG, sleep EEG recording, and registration of visual evoked potentials and somatosensory evoked potentials were normal. EEG with videomonitoring and registration of event-related potentials, however, showed abnormalities, which are discussed in detail. Our data provide further arguments in support of the hypothesis that paroxysmal kinesigenic choreoathetosis is the expression of a dysbalance in the cortico-striopallidal-thalamic loop, and has an extrapyramidal genesis.

Focal paroxysmal kinesigenic choreoathetosis

Three cases of paroxysmal kinesigenic choreoathetosis are described in whom unilateral attacks were focally induced, together with a case in whom bilateral attacks only occured. Treatment with phenytoin was effective in all cases. The aspects of the literature relating to focal and generalised attacks in paroxysmal kinesigenic choreoathetosis are reviewed.

Ten year follow-up of paroxysmal choreoathetosis: a sporadic case becomes familial

A 30-year-old woman is reported who was originally described in 1967 as an isolated instance of paroxysmal choreoathetosis. In the subsequent 10 years, her movement disorder has decreased in severity. However, she now has a 7-year-old daughter with a similar but more persistent and more serious condition. This family emphasizes both variability of manifestations of paroxysmal choreoathetosis and the importance of genetic factors.

Paroxysmal choreoathetosis following head injury

A 33-year-old man developed paroxysmal choreoathetosis following a severe head injury. Phenobarbital therapy was promptly effective. The family history as well as physical examinations and laboratory studies were unremarkable.

Familial paroxysmal dystonic choreoathetosis and its differentiation from related syndromes

Four generations of a family are described in which 7 of 8 affected members suffered from prolonged dystonic seizures; the eighth member's attacks were those of paroxysmal choreoathetosis. The attacks lasted up to 4 hours, were precipitated by alcohol, emotion, or fatigue, and responded poorly to phenytoin and barbiturates but were controlled by clonazepam. Autopsy on an affected child who died a "crib death" at the age of 2 years disclosed no major abnormality of the brain. This family appears to have the same condition as that described by Mount and Reback in 1940, Forssman in 1961, and Richards and Barnett in 1968, which the last authors termed paroxysmal dystonic choreoathetosis to distinguish it from the more common movement-induced (kinesigenic) form of the disorder. Analysis of reports of 100 cases of paroxysmal kinesigenic choreoathetosis shows that the attacks last less than 5 minutes, are precipitated by sudden movement or startle, and usually respond well to phenytoin or barbiturates. A clinical classification is presented in which the kinesigenic form is divided into a familial group (72% of cases) and a sporadic group (28% of cases) and contrasted with paroxysmal dystonic choreoathetosis. One family with an intermediate form, in which dystonic choreoathetosis was provoked by continued exertion and lasted for up to 30 minutes, is also reported.

Hereditary myokymia and periodic ataxia

A kindred in which at least 11 individuals in 3 consecutive generations have continuous muscle movement, i.e., myokymia, and periodic ataxia, has been studied. Three patients, a 24-year-old woman, her 4-year-old son and her 27-year-old sister, have been studied in detail. The disorder is inherited as an autosomal-dominant trait and presents in early childhood with attacks of ataxia of 1-2 min in duration, with associated jerking movements of the head, arms and legs. Attacks are provoked by abrupt postural change, emotional stimulus, and caloric-vestibular stimulation. At the age of 12 years approximately, facial and extremity myokymia appears. Physical findings include large calves, normal muscle strength and widespread myokymia of face, hands, arms and legs with a hand posture resembling carpopedal spasm. EMG studies at rest showed continuous spontaneous activity of otherwise normal motor units. Nerve conduction velocities were normal. Gastrocnemius biopsy in 2 patients showed fiber type grouping and small angular fibers, and was consistent with denervation. Histographic analysis of the biopsies demonstrated enlargement of both fiber types, particularly of Type I fibers. These findings are consistent with chronic denervation and an abnormality of motor neuron population or firing. The myokymia described here is of interest not only because of its genetic association with a movement disorder, but also because the muscle findings support a peripheral basis for the muscle movements.