Chorea and its disorders

Clinical Neurology in Practice: The Tongue (part 2)

BACKGROUND

The tongue is an essential organ for the development of certain crucial functions such as swallowing and speech. The examination of the tongue can be very useful in neurology, as the various types of lingual alterations can lead to certain specific diagnoses, the tongue being a kind of 'mirror' of some neurological function.

REVIEW SUMMARY

To discuss the elements of clinical examination of the tongue in relation to neurological disorders. After reviewing the different superficial lesions of the tongue, we deal with various movement disorders of the tongue (fasciculations/myokimia, orolingual tremor, choreic movements of the tongue, dystonia of the tongue, lingual myoclonus, and psychogenic movements), disorders of taste and lingual sensitivity and lingual pain.

CONCLUSIONS

Examination of the tongue should not be limited to studying its motility and trophicity. It is equally important to check the sensory function and understand how to interpret abnormal movements involving the tongue. This study also aimed to demonstrate the importance of nonmotor tongue function in neurological practice.

Dystonia, chorea, hemiballismus and other dyskinesias

Hyperkinesias are heterogeneous involuntary movements that significantly differ in terms of clinical and semeiological manifestations, including rhythm, regularity, speed, duration, and other factors that determine their appearance or suppression. Hyperkinesias are due to complex, variable, and largely undefined pathophysiological mechanisms that may involve different brain areas. In this chapter, we specifically focus on dystonia, chorea and hemiballismus, and other dyskinesias, specifically, levodopa-induced, tardive, and cranial dyskinesia. We address the role of neurophysiological studies aimed at explaining the pathophysiology of these conditions. We mainly refer to human studies using surface and invasive in-depth recordings, as well as spinal, brainstem, and transcortical reflexology and non-invasive brain stimulation techniques. We discuss the extent to which the neurophysiological abnormalities observed in hyperkinesias may be explained by pathophysiological models. We highlight the most relevant issues that deserve future research efforts. The potential role of neurophysiological assessment in the clinical context of hyperkinesia is also discussed.

Uncontrollable movements of right upper and lower extremities in a child: A diagnostic puzzle

We describe a case of a 9-year-old child who presented with uncontrollable, involuntary movements associated with a recent streptococcal infection and echocardiographic evidence of valvulitis. These findings are consistent with the diagnosis of Sydenham's chorea, a rare but important movement disorder and one of the major "Jones criteria" for the diagnosis of acute rheumatic fever. Because of its rarity, patients with Sydenham's chorea often are misdiagnosed as having a behavioral or psychiatric illness. Early recognition and appropriate management can prevent the potential severe sequelae associated with acute rheumatic fever.

Movement Disorders Related to Gluten Sensitivity: A Systematic Review

Gluten related disorders (GRD) represent a wide spectrum of clinical manifestations that are triggered by the ingestion of gluten. Coeliac disease (CD) or gluten sensitive enteropathy is the most widely recognised, but extra-intestinal manifestations have also been increasingly identified and reported. Such manifestations may exist in the absence of enteropathy. Gluten sensitivity (GS) is another term that has been used to include all GRD, including those where there is serological positivity for GS related antibodies in the absence of an enteropathy. Gluten ataxia (GA) is the commonest extraintestinal neurological manifestation and it has been the subject of many publications. Other movement disorders (MDs) have also been reported in the context of GS. The aim of this review was to assess the current available medical literature concerning MDs and GS with and without enteropathy. A systematic search was performed while using PubMed database. A total of 48 articles met the inclusion criteria and were included in the present review. This review highlights that the phenomenology of gluten related MDs is broader than GA and demonstrates that gluten-free diet (GFD) is beneficial in a great percentage of such cases.

Induction and expression of abnormal involuntary movements is related to the duration of dopaminergic stimulation in 6-OHDA-lesioned rats

Dyskinesia induction in Parkinson's disease (PD) appears less marked with long-acting dopamine agonists than with short-acting L-Dopa, but the relationship to duration of drug action is unknown. It is also unclear whether the duration of drug action affects the expression of established dyskinesia. This study compared the ability of L-Dopa and four dopamine agonists of different duration of action to induce abnormal involuntary movements (AIMs) in 6-hydroxydopamine (6-OHDA)-lesioned rats, and their ability to express established AIMs following prior exposure to L-Dopa. 6-OHDA-lesioned rats were treated with saline, L-Dopa/benserazide, apomorphine, ropinirole, pramipexole or pergolide once daily for 15 days. Repeated administration of the short-acting dopamine agonists, apomorphine (duration 80 min) and ropinirole (duration 90 min) induced marked axial, limb and orolingual AIMs at peak effect. L-Dopa (duration 100 min) produced moderate AIMs at peak effect, while administration of the long-acting dopamine agonists, pramipexole (duration 150 min) and pergolide (duration 240 min) resulted in mild AIMs. In rats primed to exhibit severe AIMs following repeated L-Dopa administration, acute administration of apomorphine, ropinirole and L-Dopa induced severe AIMs. By contrast, pramipexole and pergolide evoked only mild-moderate AIMs. Again, there was a negative correlation between duration of effect and the severity of AIMs expressed. These studies show that both the induction and expression of AIMs in 6-OHDA-lesioned rats are related to the duration of action of dopaminergic drugs. These findings suggest that continuous dopaminergic stimulation could be used both to avoid dyskinesia induction and to improve motor function in late-stage PD when troublesome dyskinesia is evident.

The detection and measurement of locomotor deficits in a transgenic mouse model of Huntington's disease are task- and protocol-dependent: influence of non-motor factors on locomotor function

Locomotor performance of transgenic R6/2 mice carrying the Huntington's disease (HD) mutation was assessed using four different tasks, fixed speed rotarod, accelerating rotarod, Digigait and footprint test. The tasks were compared directly in age- and CAG repeat-matched R6/2 mice. Accelerating rotarod was more sensitive than fixed speed rotarod for detecting early motor deficits in R6/2 mice. The sensitivity of accelerating rotarod increased with the acceleration rate and/or the start speed from which the rod accelerated. Differences between tasks were not due to inability of R6/2 mice to maintain balance at high speeds or increased fatigue on accelerating rotarod, but to difficulties in coordinating gait changes required by the constant change in speed on accelerating rotarod. The footprint test was sensitive to gait disturbances. However, surprisingly, R6/2 mice did not show major gait abnormalities on an automated treadmill task (Digigait), even though they showed overt gait deficits in the home cage. The fact that the sensitivity for detecting motor deficits depended strongly on the individual task, and on the protocol used, suggests that non-motor factors were differentially engaged in the different paradigms. We thus recommend that more than one task should be used for detecting and tracking different aspects of motor decay in animal models of HD. Since deficits in non-motor factors such as executive function and motivation may differentially influence motor outcome in each task, our results call for a more thorough investigation of the importance of higher level control of locomotion in animal models of HD.

Trombone tongue: a new clinical sign for significant medullary compression at the craniovertebral junction. Case report

The authors describe a previously unreported clinical sign that may indicate the onset of significant compression of the medulla oblongata in cases of craniovertebral junction abnormalities. This 17-year-old boy presented with mild bilateral leg weakness. Imaging studies revealed severe basilar invagination and a marked Chiari malformation. While awaiting surgery, his tongue developed an involuntary constant protrusion-intrusion repetitive motion. The onset of this so-named "trombone tongue" sign was followed shortly afterward by rapidly progressive spastic tetraparesis. After the authors performed a transmaxillary clivectomy, foramen magnum decompression, and occipitocervical fusion, they noted that the abnormal tongue motion promptly resolved and the tetraparesis gradually improved. The authors discuss their current understanding of the central control of tongue movements and present a hypothesis on the pathogenesis of trombone tongue based on the neuroanatomical basis of another abnormal tongue movement sign, lingual myoclonus.

Autoimmune neuropsychiatric disorders associated with streptococcal infection: Sydenham chorea, PANDAS, and PANDAS variants

Streptococcal infection in children is usually benign and self-limited. In a small percentage of children, prominent neurologic and/or psychiatric sequelae can occur. Sydenham chorea is the best defined and best recognized. PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection) is a well-defined syndrome in which tics (motor and/or vocal) and/or obsessive-compulsive disorder consistently exacerbate in temporal correlation to a group A beta-hemolytic streptococcal infection. PANDAS constitutes a subset of children with tics, Tourette syndrome, and obsessive-compulsive disorder. In addition to strictly defined PANDAS, we and others have recognized several PANDAS variants, including adult-onset variant, a dystonic variant, a myoclonic variant, and a "chronic" PANDAS variant. The nosology and classification of these entities are rapidly evolving. The recognition that some pediatric neurobehavioral syndromes have infectious and/or immunologic triggers points to important new avenues of disease treatment. In this review, we summarize this complex and rapidly evolving area of clinical research.

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.

Chorea and related disorders

Chorea refers to irregular, flowing, non-stereotyped, random, involuntary movements that often possess a writhing quality referred to as choreoathetosis. When mild, chorea can be difficult to differentiate from restlessness. When chorea is proximal and of large amplitude, it is called ballism. Chorea is usually worsened by anxiety and stress and subsides during sleep. Most patients attempt to disguise chorea by incorporating it into a purposeful activity. Whereas ballism is most often encountered as hemiballism due to contralateral structural lesions of the subthalamic nucleus and/or its afferent or efferent projections, chorea may be the expression of a wide range of disorders, including metabolic, infectious, inflammatory, vascular, and neurodegenerative, as well as drug induced syndromes. In clinical practice, Sydenham's chorea is the most common form of childhood chorea, whereas Huntington's disease and drug induced chorea account for the majority of adult onset cases. The aim of this review is to provide an up to date discussion of this disorder, as well as a practical approach to its management.

Neuroacanthocytosis misdiagnosed as Huntington's disease: a case report

A patient with the typical features of neuroacanthocytosis is reported. Chorea, tics, personality changes and caudate atrophy on cranial MRI resulted in an erroneous diagnosis of Huntington's disease elsewhere. Attention to other features viz., absence of ocular motility disturbances, amyotrophy, areflexia, EMG evidence of axonopathy, raised serum creatinine phosphokinase (CPK) levels and the typical erythrocytic acanthocytosis enabled us to establish the correct diagnosis. The typical features of the disease as seen in the patient are discussed. In view of the implications for genetic counseling, careful clinical and laboratory evaluation is always warranted to exclude neuroacanthocytosis in all suspected cases of Huntington's disease.

Rehabilitation of movement disorders11A commercial party with a direct financial interest in the results of the research supporting this article has conferred or will confer a financial benefit upon the author or one or more of the authors. Elovic is on the advisory board and speaker’s bureau of Allergan

This self-directed learning module highlights several movement disorders. These include dystonia, chorea, tremors, and myoclonus. A description of the clinical presentation and associated disease processes is presented. Although the discussion on treatment focuses on pharmacologic intervention, surgical options are presented when appropriate. Other movement disorders (ie, parkinsonism) are discussed elsewhere in the Study Guide.

OVERALL ARTICLE OBJECTIVES

(a) To define the various symptoms and etiologies of dystonia; (b) to define chorea and its treatment; (c) to define tremors, including associated neurologic disorders, plus pharmacologic and potential surgical interventions; and (d) to describe the symptoms, classification, and treatment of primary and secondary myoclonus.