Dystonia and chorea in acquired systemic disorders

Polycythemia and chorea

Polycythemia vera is a sporadic myeloproliferative disorder of increased red blood cell mass affecting multiple organ systems. Associated thrombosis, hemorrhaging, and hyperviscosity commonly result in neurological manifestations, sometimes in the form of chorea and ballism. Resultant choreiform movements have been mainly described as generalized with orofaciolingual and appendicular muscle involvement, hypotonia, and hyporeflexia. Chorea has also been uncommonly reported as arising from secondary causes of polycythemia; however, the underlying pathophysiology has not been clearly elucidated. Proposed mechanisms for basal ganglia dysfunction include hypoperfusion due to venous stasis, receptor hypersensitivity in a setting of reduced catecholamine levels, and altered platelet dopamine metabolism. Magnetic resonance imaging and single-photon emission computed tomography perfusion studies have failed to reveal an anatomical or physiological basis for polycythemia vera-associated chorea, yet rare pathological examinations of deceased patients have shown signs of cerebral venous thrombosis and perivenous demyelination. Administration of neuroleptics may suppress abnormal choreiform movement; however, effective management of polycythemia vera requires serial venesections in conjunction with chemotherapy. Appropriate treatment may prolong survival to more than 10 years, although chorea may spontaneously remit, re-emerge with resurgence of disease, or continue indefinitely despite maintenance therapy.

Definition and classification of hyperkinetic movements in childhood

Hyperkinetic movements are unwanted or excess movements that are frequently seen in children with neurologic disorders. They are an important clinical finding with significant implications for diagnosis and treatment. However, the lack of agreement on standard terminology and definitions interferes with clinical treatment and research. We describe definitions of dystonia, chorea, athetosis, myoclonus, tremor, tics, and stereotypies that arose from a consensus meeting in June 2008 of specialists from different clinical and basic science fields. Dystonia is a movement disorder in which involuntary sustained or intermittent muscle contractions cause twisting and repetitive movements, abnormal postures, or both. Chorea is an ongoing random-appearing sequence of one or more discrete involuntary movements or movement fragments. Athetosis is a slow, continuous, involuntary writhing movement that prevents maintenance of a stable posture. Myoclonus is a sequence of repeated, often nonrhythmic, brief shock-like jerks due to sudden involuntary contraction or relaxation of one or more muscles. Tremor is a rhythmic back-and-forth or oscillating involuntary movement about a joint axis. Tics are repeated, individually recognizable, intermittent movements or movement fragments that are almost always briefly suppressible and are usually associated with awareness of an urge to perform the movement. Stereotypies are repetitive, simple movements that can be voluntarily suppressed. We provide recommended techniques for clinical examination and suggestions for differentiating between the different types of hyperkinetic movements, noting that there may be overlap between conditions. These definitions and the diagnostic recommendations are intended to be reliable and useful for clinical practice, communication between clinicians and researchers, and for the design of quantitative tests that will guide and assess the outcome of future clinical trials.

Use of antiepileptic drugs for hyperkinetic movement disorders

Many studies investigated the use of antiepileptic drugs (AEDs) in several neurological diseases other than epilepsy. These neurological disorders, usually, involve neuronal excitability through the modulating of ion channels, receptors and intracellular signaling pathways, and are the targets of the AEDs. This article provides a review of the clinical efficacy of both conventional and newer AEDs in hyperkinetic movement disorders. Some of these indications for AEDs have been established, while others are under investigation. The modulation of GABAergic transmission may explain the neuronal hyper-excitability that underlies some forms of hyperkinetic movement disorders. So, AEDs able to increase GABAergic neurotransmission may play a role in hyperkinetic movement disorders treatment. Therefore, AEDs could represent a useful therapeutic option in the management of hyperkinetic movement disorders where the available treatments are ineffective.

Photophobia in essential blepharospasm--a positron emission tomographic study

To localize regional alterations in cerebral glucose metabolism in essential blepharospasm (EB) patients with photophobia. We have studied 22 EB patients by performing positron emission tomography and [(18)F]-fluorodeoxyglucose analysis. The patients were classified into two subgroups, namely, EB with photophobia (P group) and EB without photophobia (NP group), and compared with a healthy control group (n = 44). There were no significant differences between the two patient groups with respect to the severity of motor symptoms or the duration for which the condition persisted. The FDG-PET images were analyzed using the statistical parametric mapping software. As compared to the control group, the P group exhibited significant hypermetabolism in the thalamus (P = 0.002), while the NP group exhibited significant hypometabolism in the dorsal midbrain, especially, in the superior colliculus (P = 0.005). The P group exhibited significant hypermetabolism in the thalamus and the dorsal midbrain as compared to the NP group (P < 0.001). These findings suggest that photophobia in EB patients may be associated with abnormal hyperactivity in the thalamus. Either hyperactivity of the thalamus or hypoactivity of the superior colliculus, or both may be associated with excessive blinking in these patients.

Different phenotypy in three siblings with homocystinuria

INTRODUCTION

Movement disorders associated with homocystinuria have been reported as rare cases. Their physiopathology has not yet been clarified.

METHODS

Three siblings in the same family have been described, all with homocystinuria but possessing phenotypic differences.

RESULT

The first case presented oromandibular dyskinesia, spasmodic dysphonia, tremor, bradykinesia, and generalized dystonia along with the classic findings of homocystinuria. The second case had marfanoid features and ophthalmic complications of homocystinuria, and also evidence of mild rigidity of which the patient did not complain. The third case had only marfanoid features. The most severely affected family member was the first case who also had increased thyroid peroxidase antibodies, antithyroglobulin antibodies, and thyroiditis.

CONCLUSION

The most severely affected sibling presented movement disorders and evidence of autoimmune thyroiditis. These findings have led us to think that research on the relations between movement disorders, basal ganglia, immunity, autoimmune thyroid diseases, and homocysteine should be continued.

Generalized chorea induced by an unilateral anterior cerebral artery territorial infarction

Generalized chorea caused by unilateral cerebral infarction has rarely been reported. A 58-year-old woman presented involuntary movement in her all extremities after acute cerebral infarction on her right anterior cerebral artery territory. The involuntary movements were diagnosed as generalized chorea. We didn’t find any cause of generalized chorea except the acute cerebral infarction. Here, we described the case of generalized chorea after unilateral cerebral infarction discussing the possible mechanisms.

[Vascular hemiballismus due to extraluysian lesions]

INTRODUCTION

Hemiballismus is a very rare disorder; less than 7% of all hyperkinetic disorders. Classically, a lesion of the contralateral corpus Luysii is involved. We report a case of hemiballismus due to an extraluysian lesions and discuss the underlying pathophysiology.

CASE REPORT

A 74-year-old women, with a history of diabetes and hypertension, developed left-sided hemiballismus one week before admission. The brain MRI showed a right lenticular nucleus hematoma with vascular leucoencephalopathy. The patient was given haloperidol and recovered well. The brain MRI showed the integrity of both corpus Luysii.

CONCLUSION

Hemiballismus has been classically characterized as pathognomonic of a lesion in the contralateral corpus Luysii. However, many cases due to an extraluysian lesion of the striatum, caudate or thalamus have been reported recently. Prognosis is benign in most cases.

No evidence of perfusion abnormalities in the basal ganglia of a patient with generalized chorea-ballism and polycythaemia vera: analysis using subtraction SPECT co-registered to MRI

Polycythaemia vera is a well-known cause of symptomatic chorea, however, the pathophysiology of this correlation remains unclear. We report on a patient with generalized chorea-ballism associated with polycythaemia vera, and we present the findings of 99mTc-hexamethylpropylene amine oxime (HMPAO) SPECT done in both the choreic state and the non-choreic state. The SPECT during both the choreic and the non-choreic states did not reveal any definite perfusion changes in specific regions of the brain, as compared with 6 age-matched controls. In addition, the subtraction SPECT co-registered to MRI (SISCOM) analysis did not show any difference in cerebral blood flow during the choreic and non-choreic states. This result suggests that the basic mechanism of chorea associated with polycythaemia vera does not appear to be associated with a reduction in cerebral perfusion to a specific cerebral area, such as the basal ganglia or its thalamocortical connections.

Movement disorders and inborn errors of metabolism in adults: a diagnostic approach

Inborn errors of metabolism (IEMs) may present in adolescence or adulthood with various movement disorders including parkinsonism, dystonia, chorea, tics or myoclonus. Main diseases causing movement disorders are metal-storage diseases, neurotransmitter synthesis defects, energy metabolism disorders and lysosomal storage diseases. IEMs should not be missed as many are treatable. Here we briefly review IEMs causing movement disorders in adolescence and adults and propose a simple diagnostic approach to guide metabolic investigations based on the clinical course of symptoms, the type of abnormal movements, and brain MRI abnormalities.

Striatal and nigral pathology in a lentiviral rat model of Machado-Joseph disease

Machado-Joseph disease (MJD) is a fatal, dominant neurodegenerative disorder. MJD results from polyglutamine repeat expansion in the MJD-1 gene, conferring a toxic gain of function to the ataxin-3 protein. In this study, we aimed at overexpressing ataxin-3 in the rat brain using lentiviral vectors (LV), to generate an in vivo MJD genetic model and, to study the disorder in defined brain regions: substantia nigra, an area affected in MJD, cortex and striatum, regions not previously reported to be affected in MJD. LV encoding mutant or wild-type human ataxin-3 was injected in the brain of adult rats and the animals were tested for behavioral deficits and neuropathological abnormalities. Striatal pathology was confirmed in transgenic mice and human tissue. In substantia nigra, unilateral overexpression of mutant ataxin-3 led to: apomorphine-induced turning behavior; formation of ubiquitinated ataxin-3 aggregates; alpha-synuclein immunoreactivity; and loss of dopaminergic markers (TH and VMAT2). No neuropathological changes were observed upon wild-type ataxin-3 overexpression. Mutant ataxin-3 expression in striatum and cortex, resulted in accumulation of misfolded ataxin-3, and within striatum, loss of neuronal markers. Striatal pathology was confirmed by observation in MJD transgenic mice of ataxin-3 aggregates and substantial reduction of DARPP-32 immunoreactivity and, in human striata, by ataxin-3 inclusions, immunoreactive for ubiquitin and alpha-synuclein. This study demonstrates the use of LV encoding mutant ataxin-3 to produce a model of MJD and brings evidence of striatal pathology, suggesting that this region may contribute to dystonia and chorea observed in some MJD patients and may represent a target for therapies.

Delayed-onset dystonia due to perinatal asphyxia: a prospective study

The objective of this work was to establish the existence and incidence of possible delayed-onset dystonia in a cohort of infants with diagnosed perinatal asphyxial hypoxic-ischemic encephalopathy (HIE). This prospective study comprised 103 survivors of perinatal asphyxial HIE, who were regularly followed and neurologically examined in the course of 7 to 13 years after birth (median 10 years). Neurological outcome at the end of the follow-up period was normal in 87 (84.5%) patients, while in 7 (6.8%) only mild neurological signs were detected (behavioral disturbances in 3, clumsiness in 2, and hypotonia in 1 patient). Severe cerebral palsy was diagnosed in nine patients (8.7%). Only one patient was diagnosed with possible delayed-onset segmental dystonia. At the age of 4 years he developed cervical dystonia with spread to one arm in the course of 1.5 years (segmental dystonia) and then stabilized. Other known causes of dystonia, including a DYT1 mutation, were excluded. Our preliminary data suggest that over the course of at least 7 years after birth, approximately 1% of infants who survived perinatal asphyxial HIE would develop delayed-onset dystonia.

Benign hereditary chorea: clinical, neuroimaging, and genetic findings

Benign hereditary chorea is an autosomal dominant disease with an early onset of symptoms. In some families, symptoms tend to decrease in adulthood, suggesting that the disorder results from a developmental disturbance in the brain. Individuals with benign hereditary chorea, a nonprogressive disease, have normal or slightly below normal intelligence. The locus for benign hereditary chorea is on chromosome 14. Benign hereditary chorea is a result of mutations in the thyroid transcription factor 1 gene. Previous neuroimaging and pathological investigations of the brain showed no notable abnormalities in patients with this condition. In this study, 5 patients from 1 family with typical clinical features of benign hereditary chorea are presented. Clinical severity varied considerably in the family. Brain magnetic resonance imaging results were normal. Brain single photon emission computed tomography in 3 children, performed 1 hour after intravenous injection of 0.35 mCi/kg of body weight of technetium 99m ethyl cysteinate dimer, showed markedly decreased uptake in the right striatum and the right thalamus in 1 child. The oldest child had mildly reduced uptake in the right putamen and the left thalamus. Brain single photon emission computed tomographic findings in the youngest child were normal. Contrary to other reports of radionuclide brain imaging, notable brain single photon emission computed tomography changes were detected in 2 of 5 patients. Brain single photon emission computed tomography findings did not seem to correlate with the clinical status of the children.

Efficacy of intravenous immunoglobulin treatment in lupus erythematosus chorea

Chorea is a rare complication of systemic lupus erythematosus (SLE) and is strongly related to the presence of antiphospholipid antibodies. Various infections may also be triggering factors in the development of choreiform movements. Additionally, Salmonella infection is the most common opportunistic bacterial infection in SLE patients. We report a case of a 33-year-old woman with SLE who developed lupus erythematosus-associated chorea with multiple involuntary movements and cognitive disturbances. Because the methylprednisolone therapy administered appeared to lead to Salmonella enteritidis infection, intravenous immunoglobulin (IVIg) in a total dose 100 g was administered after which a remarkable improvement of the abnormal movements and cognitive function was noted. Within 7 days, the patient had returned to normal. We therefore conclude that IVIg therapy may be an effective therapeutic approach for the treatment of the acute cerebral complications of SLE, especially in cases in whom other therapeutic strategies are ineffective or harmful.

Chorea-Ballism as a Manifestation of Decompensated Type 2 Diabetes Mellitus

Chorea and ballism are movement disorders that result from a variety of conditions. Hyperglycemia is an unusual recognized cause of these movement disorders. We report 3 cases of new-onset chorea-ballism induced by nonketotic hyperglycemia in elderly patients, highlighting that chorea may be the first manifestation of undiagnosed decompensated diabetes mellitus.

Geriatric Chorea

The differential diagnosis, diagnostic evaluation, and treatment of late-onset chorea are reviewed. Late-onset chorea is rare and has a heterogeneous causation. A systematic approach to geriatric chorea greatly enhances a correct diagnosis. An accurate diagnosis is important because many causes of chorea are treatable or or, when heritable, may have significant implications for subsequent generations. Most late-onset chorea is either nonlimiting, requiring no treatment, has a spontaneous remission, or responds to medication. In a minority of patients, chorea is medically refractory or manifestation of an untreatable disorder.

3-Nitropropionic acid: a mitochondrial toxin to uncover physiopathological mechanisms underlying striatal degeneration in Huntington's disease

Huntington's disease (HD) is a neurodegenerative disorder caused by a mutation in the gene encoding Huntingtin. The mechanisms underlying the preferential degeneration of the striatum, the most striking neuropathological change in HD, are unknown. Of those probably involved, mitochondrial defects might play an important role. The behavioural and anatomical similarities found between HD and models using the mitochondrial toxin 3-nitropropionic acid (3NP) in rats and primates support this hypothesis. Here, we discuss the recently identified mechanisms of 3NP-induced striatal degeneration. Two types of important factor have been identified. The first are the 'executioner' components that have direct roles in cell death, such as c-Jun N-terminal kinase and Ca2+-activated protease calpains. The second are 'environmental' factors, such as glutamate, dopamine and adenosine, which modulate the striatal degeneration induced by 3NP. Interestingly, these recent studies support the hypothesis that 3NP and mutated Huntingtin have certain mechanisms of toxicity in common, suggesting that the use of 3NP might give new insights into the pathogenesis of HD. Research on 3NP provides additional proof that the neurochemical environment of a given neurone can determine its preferential vulnerability in neurodegenerative diseases.

Homocysteine and serum markers of immune activation in primary dystonia

The cause of primary dystonia remains unknown. Several reports point to immune system disturbances in primary dystonia and a recent study demonstrated hyperhomocysteinemia in cervical dystonia. Homocysteine (HCY) is an amino acid and elevated HCY concentrations were shown to be associated with immune system activation and increased neopterin serum concentrations. We examined HCY serum concentrations together with serum markers of immune activation in patients with different types of primary dystonia. Eighty-three patients with different types of primary dystonia were included and investigated at least 3 months following botulinum toxin treatment. Thirty-six healthy volunteers with similar age and sex distribution served as controls. Total serum HCY, kynurenine, and tryptophan concentrations were determined by high-performance liquid chromatography; neopterin, folate, and vitamin B12 concentrations were measured by immunoassays. Routine blood analysis, including C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and white blood count (WBC), was performed. Patients with primary dystonia had significantly higher HCY concentrations compared to controls. Among the dystonia subtypes, no significant difference of HCY serum concentrations was observed. CRP and ESR were within the normal range in >90% of the patients and all had normal WBC. Neopterin, kynurenine, and tryptophan serum concentrations were similar in patients and controls and not correlated with HCY serum concentrations. The results provide evidence against enhanced cellular immune activation in patients with primary dystonia. However, hyperhomocysteinemia was present in all dystonia subtypes and unrelated to immune activation in this study. HCY is a neuronal excitotoxic amino acid and hyperhomocysteinemia is considered an independent vascular risk factor. Further studies are required to define the background of hyperhomocysteinemia in primary dystonia.

Rupture of quadriceps tendon in a patient with postanoxic choreoathetosis

PURPOSE

To describe a case of quadriceps tendon rupture in a patient with postanoxic choreoathetotic movements.

CASE REPORT

A 20-year-old man was admitted to a rehabilitation hospital after anoxic brain injury. As a result of the injury, he developed continuous flowing choreoathetotic movements. He contracted fever and swollen and painful right knee, and only when periarticular edema decreased did a suprapatellar gap appear and quadriceps tendon rupture was diagnosed.

CONCLUSIONS

Considering the possibility of tendon rupture when evaluating a patient with non-volitional movements and 'arthritic' presentation in a rehabilitation setting, may prevent delay of quadriceps surgical repair.

Systemic diseases that cause movement disorders

The present review is aimed at providing practical assistance to the clinical neurologist in reaching a diagnosis, understanding the pathogenic mechanisms of movement disorders associated with systemic diseases, and determining appropriate therapy. Infectious disease by direct effect or as an acquired autoimmune neurological disease, stroke, hypoxia-ischemia, paraneoplastic syndromes, collagen disorders, endocrine, liver and kidney diseases that may cause hypokinetic or hyperkinetic abnormal movement are considered separately. The type and evolution of abnormal movement caused by systemic disease vary with age and underlying pathology. Therapy for abnormal movements should include a primary treatment for the systemic disease.

Hemichorea with antiphospholipid antibodies in a patient with lupus nephritis

Although central nervous system involvement is an important manifestation of systemic lupus erythematosus (SLE), chorea is a relatively uncommon complication. A strong association between chorea and the presence of antiphospholipid antibodies (aPLs) has been reported in patients with SLE, lupus-like disease, or primary antiphospholipid syndrome. We describe a patient with lupus nephritis and cerebral infarction, who subsequently developed recurrent hemichorea associated with increased aPLs levels. A 7-year-old boy suffered from lupus nephritis and a left middle cerebral artery infarction associated with aPLs. He subsequently experienced two episodes of right hemichorea associated with increased aPLs levels without any evidence of further neurological lesions by brain computed tomography or magnetic resonance imaging. The previous left cerebral artery infarction might have increased the susceptibility of the left basal ganglia to the effects of aPLs that contributed to the development of the right hemichorea in this patient.

Hemichorea: a rare presentation of tuberculoma

Hemichorea due to tuberculoma has not been reported. We managed a 16-year-old girl who developed transient left hemichorea due to right sided striatal tuberculoma. Chorea regressed following 1 week of antitubercular treatment with corticosteroid therapy and disappeared at 3 months. In a patient presenting with chorea, striatal tuberculoma should also be considered especially in the area where tuberculosis is prevalent.

Progressive delayed-onset dystonia after cerebral anoxic insult in adults

The basal ganglia, especially the globi pallidi (GP), are highly vulnerable to generalized cerebral anoxia/hypoxia. We report on 2 new cases with delayed-onset generalized dystonia due to cerebral anoxia. The onset of dystonia in both of our patients was delayed by about 2 months. In both cases, the unusual feature was the progressive worsening and the spread of dystonia over many years after delayed onset. Dystonia progressed for 16 years in Case 1 and for 4 years in Case 2. Furthermore, initial magnetic resonance imaging (MRI) scan of Case 1 showed mild changes of the internal capsule sparing the basal ganglia. Years later, in line with clinical progression, the follow-up MRI scan showed isolated bilateral lesions involving the entire GP. MRI scans in Case 2 showed bilateral lesions of caudate and lentiform nuclei. There may be several mechanisms underlying delayed and progressive symptoms after time-limited brain anoxia. We hypothesize that anoxia-induced excitotoxicity resulting in mitochondrial dysfunction and subsequent apoptosis may explain, at least partly, the delayed-onset and progressive extrapyramidal syndromes seen in these patients.

The neuropathology and pathogenesis of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic, multisystem, autoimmune disease in which neuropsychiatric involvement occurs in about 50% of patients and carries a poor prognosis. Despite extensive research, the precise mechanisms of nervous tissue injury remain the least well understood. This article summarizes the important clinical neuropsychiatric features of SLE and, reviewing classical histopathological and more recent experimental studies, discusses theories concerning their presumed pathogenesis. The distinctive production of diverse autoantibodies seems to be related to defective clearance of apoptotic cells. Antibody-mediated neural cell injury and rheological disturbances represent the two principal suggested mechanisms of tissue injury. An interplay between these processes, underlying genetic factors, their modification by hormones, complicated by a number of secondary factors, may explain the wide spectrum of features encountered in this disease.

Antiphospholipid syndrome and dystonia-parkinsonism. A case report

Background: Although clinically evident and MRI confirmed, basal ganglia involvement, is usual in primary antiphospholipid syndrome, extrapyramidal disorders such as parkinsonism and dystonia are very rare. We were unable to find any report in the literature on dystonia-parkinsonism in patients with primary antiphospholipid syndrome. Here we report an adult patient with dystonia-parkinsonism and primary antiphospholipid syndrome.Case report: A 60 year old, right-handed man came to our attention due to writer's cramp, bradykinesia and stiffness of his right hand. Neurological examination revealed constant, marked dystonic posturing, rigidity and bradykinesia of the right hand. Hyper-gammaglobulinemia was demonstrated on electrophoresis-serum IgG was increased. Anticardiolipin antibodies were examined by counterimmunoelectrophoresis (ELISA): IgG was negative, while IgM was positive. There was also slight thrombocytopenia. Magnetic resonance imaging brain scan axial T2W/UTSE revealed several hyperintense lesions in the basal ganglia and in the periventricular white matter and diffuse hyperintensity of the subcortical white matter bilaterally in the parietal regions. There was asymmetric parenchimal atrophy, more prominent in the left hemisphere. No clinical improvement was achieved by levodopa, dopamine agonists or anticholinergics. According to the criteria for primary antiphospholipid syndrome our patient had thrombocytopenia and high levels of IgG and IgM anticardiolipin antibodies so he was presumed to have a primary antiphospholipid syndrome.Conclusion: Various movement disorders may appear secondary to stroke, antiphospholipid syndrome, Behcet's disease or brain tumor. These cases may help in the understanding of pathophysiology of movement disorders. Dystonia and parkinsonism as well as other movement disorders may be associated with primary antiphospholipid syndrome.

Pallido-Luysio-Nigral atrophy revealed by rapidly progressive hemidystonia: a clinical, radiologic, functional, and neuropathologic study

Pallido-luysio-nigral atrophy (PLNA) is a rare neurodegenerative disease in which the clinical and radiologic correlates have not yet been clearly established. A 62-year-old man insidiously developed dystonic postures, choreoathetoid movements, slowness, and stiffness, which initially affected the right hand and foot and progressively spread to the entire right side. T2-weighted magnetic resonance imaging showed increased signal intensity in both left and right medial pallida and in the left substantia nigra. Tests using HMPAO-SPECT and FDG-PET demonstrated left cortical hyperperfusion and hypermetabolism, whereas the left lenticular nucleus was slightly hypometabolic. At age 65, abnormal movements and postures involved all four limbs and the axis causing major gait disturbances, and facial and bulbar muscles atrophied resulting in dysarthria, dysphagia, and impaired breathing. Diffuse amyotrophy and fasciculations also appeared. Death occurred at age 66, 4 years after onset. At autopsy, severe bilateral neuronal loss and gliosis restricted to the pallidum, the subthalamic nucleus, the substantia nigra, and the hypoglossal nucleus were noted, accounting for the diagnosis of PLNA with lower motor neuron involvement. Progressive hemidystonia with adult onset represents an unusual clinical presentation for this disorder. Moreover, this observation indicates that a diagnosis of PLNA should be considered for specific magnetic resonance imaging, SPECT, and/or PET data, and suggests that in PLNA, pallidal dysfunction might play a key role in the dystonic presentation.

[Psychogenic dystonia: report of 2 cases]

Movement disorders have rarely been the result of psychiatric disturbances. Psychogenic dystonia is caracterized by inconsistent findings, a known precipitant factor, onset in legs, pain, multiple somatizations and incongruent association with other movement disorders. We report two patients with clinically established psychogenic dystonia. Patient 1: a female that presented sudden loss of strength in her four limbs; she developed feet dystonia, alternant laterocollis, generalized and irregular tremor, and limb hypertonia that disappeared with distraction; psychological examination showed severe depression, hypochondria and obsessive disorder. Patient 2: a female that presented with irregular limb tremors that disappeared with distraction and left foot dystonia nine years ago; she gradually lost her walk capacity; she complained pain in lumbar area and in her left limb, psychological examination showed infantile behaviour, low frustration tolerance, impulsivity and self-aggression. Their complementary exams showed no alterations and they had no response to specific pharmacological treatment. Dystonia is rarely psychogenic, but this etiology is suggested when clinical characteristics are inconsistent and incongrous with a classical disorder. It should be part of differential diagnosis when appears in association with other somatization or psychiatric disorders.

Influenza A encephalitis with movement disorder

Influenza A is an uncommon but well-recognized cause of viral encephalitis in childhood, occurring most commonly during community influenza outbreaks. The authors report four cases of influenza A encephalitis that occurred during an Australian epidemic in 1997-1998. Choreoathetosis during the acute phase of infection or basal ganglia involvement on neuroimaging was observed in three of the four patients. These findings in pediatric encephalitis are suggestive of influenza A infection and may guide investigation and early diagnosis.