Suspected paroxysmal dyskinesia in four small-breed dogs: Clinical presentation, diagnosis, management and prognosis.

This case report details the clinical presentation, diagnosis, management and prognosis of paroxysmal dyskinesia (PD) in four small-breed dogs, each weighing under 6 kg: A 7-year-old spayed female Pomeranian, an 8-year-old female mixed breed, a 1-year-old female Pomeranian and a 9-year-old castrated male Poodle. These dogs were referred to our hospital due to movement disorders. Diagnosis was facilitated by video recordings of the episodes, assessing motor activity, consciousness, episode duration, any pre- or post-episodic behaviour as well as the presence of autonomic signs. Magnetic resonance imaging conducted on two of the dogs returned unremarkable results. Treatment trials included a gluten-free diet for all four dogs, with two also receiving acetazolamide. This intervention led to a decrease in the frequency of abnormal movement in all patients. Our findings suggest that PD in dogs can be effectively diagnosed through detailed symptom description using videos and questionnaires. Furthermore, once diagnosed, a combination of nutritional and medical management can be beneficial.

Paroxysmal movement disorders.

Paroxysmal movement disorders include two groups of intermittent neurologic disorders: paroxysmal dyskinesia, in which episodes of involuntary hyperkinetic movements (mainly chorea and/or dystonia) occur with preserved consciousness, and episodic ataxias, which are characterized by discrete attacks of cerebellar dysfunction, sometimes associated with progressive ataxia. Since episodic ataxias are individually discussed in Chapter 8 of this volume, we herein provide a deep overview of phenotypic, genetic, pathophysiologic, diagnostic, and treatment aspects of paroxysmal dyskinesia, following the trigger-based nomenclature which distinguishes paroxysmal kinesigenic dyskinesia, paroxysmal nonkinesigenic dyskinesia, and paroxysmal exercise-induced dyskinesia. Emerging paroxysmal dyskinesia not fulfilling the criteria for the above-mentioned subtypes will also be discussed. Phenotypic and genotypic overlap among paroxysmal movement disorders, epilepsy, and migraine have progressively emerged, thus shedding light on a shared pathophysiologic framework. Advances in our understanding of the pathomechanisms underlying paroxysmal movement disorders, which involve dysfunctions of ion channels, proteins associated with the vesical synaptic cycle machinery, and proteins involved in neuronal energy metabolism, point toward a discrete number of converging pathophysiologic pathways and may lay foundations for developing target-specific therapies.

Late-onset Chorea with a Rare but Identifiable Cause.

Chorea is a very commonly encountered movement disorder; it has various etiologies, and it can have autoimmune, vascular, degenerative, or paraneoplastic etiology. Our patient had acute onset chorea and a strong history of smoking, which made us suspect first vascular followed by paraneoplastic cause. After ruling out common vascular and metabolic causes, his whole body positron emission tomography (PET) scan revealed a mass in the right upper lobe, a biopsy revealed a small cell carcinoma lung and a paraneoplastic panel showed antibodies positive for collapsin response mediator protein 5 antigen (CRMP-5/CV2); the patient was started on immunomodulation, chemotherapy with the variable response, he succumbed to a cardiac event after treatment.

Insights from European Reference Network for rare neurological disorders study surveys on diagnosis, treatment, and management of NKX2-1-related disorders.

BACKGROUND: NKX2-1-related disorder (NKX2-1-RD) is a rare disease characterized by a triad of primary hypothyroidism, neonatal respiratory distress, and neurological features, including chorea. OBJECTIVE: This study aimed to identify discrepancies in the management of NKX2-1-RD among European Union (EU) specialists. METHODS: The ERN-RND Chorea & Huntington disease group designed a survey to conduct a cross-sectional multicenter study on the management of NKX2-1-RD. Descriptive analysis was performed, and total responses are presented for each item. RESULTS: The study involved 23 experts from 13 EU countries with experience in evaluating hyperkinetic patients with NKX2-1-RD: 11 were adult specialists, and 12 were pediatric specialists. NKX2-1-RD diagnosis was made at different ages, with the most common initial symptoms being hypotonia and/or motor developmental delay (reported by 11 experts) and chorea (reported by 8 experts). Chorea involved various body parts and showed improvement as reported by 9 experts, stabilization by 12 experts, and worsening by 2 experts with age. The pharmacological treatment of chorea varied widely among the experts. Misdiagnosis was reported by 14 experts. NKX2-1 pathogenic variants or deletions were confirmed in >75 % of patients (reported by 12 experts). Pulmonary and endocrinology evaluations were requested by 7 and 12 experts, respectively. The management of psychiatric comorbidities also varied among the different experts. CONCLUSIONS: This study highlights the need for a clinical practice guideline for the management of NKX2-1-RD to ensure that patients across the EU receive consistent and appropriate care. Such a guideline would benefit both doctors and healthcare practitioners.

Chorea - Is Diabetes Mellitus the Cause?

Diabetic striatopathy (DS) is an uncommon complication of diabetes characterized by hemiballismus-hemichorea, often accompanied by reversible striatal hyperintensity on neuroimaging. Diabetes is the most common metabolic cause of hemiballismus and hemichorea. However, it is underreported as clinicians do not always consider it in the diagnosis of new movement abnormalities. The prognosis is generally excellent, and management involves glycemic control and anti-chorea medications. We present a case of a patient with bilateral chorea and ballismus and classic MRI findings of DS, though his history of diabetes and substance use confounds the clinical picture of DS.

Differential diagnosis of Huntington's disease- neurological aspects of NKX2-1-related disorders.

Benign hereditary chorea (BHC) is an inherited neurological disorder consisting of childhood-onset, nonprogressive chorea, generally without any other manifestations. In most reported cases, the inheritance of BHC is autosomal dominant but both incomplete penetrance and variable expressivity are observed and can be caused by NKX2-1 mutations. The spectrum contains choreoathetosis, congenital hypothyroidism, and neonatal respiratory distress syndrome. The neurological symptoms can be misdiagnosed as Huntington's disease (HD). The two Polish families were diagnosed with NKX2-1 gene mutations and a literature review concerning the NKX2-1-related disorders was conducted. All family members were examined by experienced movement disorders specialists. PubMed database was searched to obtain previously described NKX2-1 cases. Whole exome sequencing (WES) was performed in one proband (Family A) and direct NKX2-1 sequencing in the second (Family B). Two Polish families were diagnosed with NKX2-1 gene mutations (p.Trp208Leu and p.Cys117Alafs*8). In one family, the co-occurrence of HD was reported. Forty-nine publications were included in the literature review and symptoms of 195 patients with confirmed NKX2-1 mutation were analyzed. The most common symptoms were chorea and choreiform movements, and delayed motor milestones. The NKX2-1 mutation should always be considered as a potential diagnosis in families with chorea, even with a family history of HD. Lack of chorea does not exclude the NKX2-1-related disorders.

Movement Disorders in Patients with Subacute Sclerosing Panencephalitis: A Systematic Review.

BACKGROUND: Subacute sclerosing panencephalitis (SSPE) is a complication of measles, occurring after a latency of 4-10 years. It continues to occur in developing countries although resurgence is being reported from developed countries. Characteristic features include progressive neuropsychiatric issues, myoclonus, seizures, movement disorders and visual impairment. Electroencephalography (EEG) typically shows periodic generalized discharges, and elevated CSF anti-measles antibodies are diagnostic. Movement disorders are being increasingly recognized as part of the clinical spectrum, and range from hyperkinetic (chorea, dystonia, tremor, tics) to hypokinetic (parkinsonism) disorders and ataxia. OBJECTIVES: This article aims to comprehensively review the spectrum of movement disorders associated with SSPE. METHODS: A literature search was conducted in PubMed and EMBASE databases in December 2023 and articles were identified for review. RESULTS: Movement disorders reported in SSPE included hyperkinetic (chorea, dystonia, tremor and tics), hypokinetic (parkinsonism), ataxia and extraocular movement disorders. Myoclonus, a core clinical feature, was the most frequent "abnormal movement." Movement disorders were observed in all clinical stages, and could also be a presenting feature, even sans myoclonus. Hyperkinetic movement disorders were more common than hypokinetic movement disorders. An evolution of movement disorders was observed, with ataxia, chorea and dystonia occurring earlier, and parkinsonism later in the disease. Neuroradiological correlates of movement disorders remained unclear. CONCLUSION: A wide spectrum of movement disorders was observed throughout the clinical stages of SSPE. Most data were derived from case reports and small case series. Multicentric longitudinal studies are required to better delineate the spectrum and evolution of movement disorders in SSPE.

Atypical Presentations of Huntington Disease-like 2 in South African Individuals.

BACKGROUND: Huntington disease-like 2 (HDL2) is a neurodegenerative disorder, affecting only individuals of African ancestry. Full penetrance occurs in individuals with 40 repeats or more. OBJECTIVE: To describe the phenotypic variability of HDL2 in a group of mixed ancestry individuals from South Africa. METHODS: Eight patients were assessed with analysis of repeat size and magnetic resonance brain imaging. We applied the Unified Huntington's Disease Rating Scale (UHDRS), but in deceased patients (4), this was estimated from video material. RESULTS: Cognitive domains were more severely affected than motor; UHDRS motor scores were notable for bradykinesia, and to a slightly lesser extent, for rigidity and dystonia; a single patient had marked chorea. Repeat lengths ranged from 45 to 63 (median, 52). CONCLUSION: This South African group of mixed ancestry HDL2 individuals presented with severe cognitive and behavioral impairments, with lesser degrees or absence of chorea. This presentation is possibly related to large repeat sizes.

Hemichorea-hemiballismus due to diabetic striatopathy a serious complication of uncontrolled diabetes.

We report the case of a man in his mid-80s with diabetes mellitus who presented to the emergency department with a 1-day history of right-sided choreiform movements and falls. Laboratory tests revealed blood glucose of 597 mg/dL. Non-contrast CT imaging of his head demonstrated a faint hyperdensity involving the left lentiform nucleus and brain MRI showed a hyperintensity in the left basal ganglia on T1-weighted images. These lesions are typical of diabetic striatopathy. Symptoms of hemichorea/hemiballismus did not resolve with glycaemic control and several pharmacological agents were tried with eventual improvement with risperidone. He was discharged to a rehabilitation facility and had mild persistent arm chorea at 6-month follow-up.

Dancing Out of Step: A Case of Tuberculous Meningitis Presenting as Childhood Chorea.

Background: Acute to subacute pediatric movement disorders require prompt diagnosis to identify potentially treatable diseases. Case Report: We present a 6-year-old male with a three-week history of generalized chorea transitioning to predominantly right-sided hemichorea and then to left hemiplegia. Discussion: We review the mechanisms in tuberculous meningitis underlying his movement abnormalities.

Adult-onset acute rheumatic fever with chorea and carditis.

Rheumatic fever is a major cause of cardiovascular morbidity and mortality in low-income and middle-income countries, and it usually occurs at a young age. Adult-onset acute rheumatic fever is a rare condition and usually represents a recurrence of childhood-onset disease. We report a case of an elderly man presenting with rheumatic carditis and rheumatic chorea subsequently diagnosed with adult-onset rheumatic fever.

Genetic testing for non-parkinsonian movement disorders: Navigating the diagnostic maze.

Genetic testing has become a valuable diagnostic tool for movement disorders due to substantial advancements in understanding their genetic basis. However, the heterogeneity of movement disorders poses a significant challenge, with many genes implicated in different subtypes. This paper aims to provide a neurologist's perspective on approaching patients with hereditary hyperkinetic disorders with a focus on select forms of dystonia, paroxysmal dyskinesia, chorea, and ataxia. Age at onset, initial symptoms, and their severity, as well as the presence of any concurrent neurological and non-neurological features, contribute to the individual clinical profiles of hereditary non-parkinsonian movement disorders, aiding in the selection of appropriate genetic testing strategies. There are also more specific diagnostic clues that may facilitate the decision-making process and may be highly specific for certain conditions, such as diurnal fluctuations and l-dopa response in dopa-responsive dystonia, and triggering factors, duration and frequency of attacks in paroxysmal dyskinesia. While the genetic and mutational spectrum across non-parkinsonian movement disorders is broad, certain groups of diseases tend to be associated with specific types of pathogenic variants, such as repeat expansions in many of the ataxias. Some of these pathogenic variants cannot be detected by standard methods, such as panel or exome sequencing, but require the investigation of intronic regions for repeat expansions, such as Friedreich's or FGF14-linked ataxia. With our advancing knowledge of the genetic underpinnings of movement disorders, the incorporation of precise and personalized diagnostic strategies can enhance patient care, prognosis, and the application and development of targeted therapeutic interventions.

[The value of re-evaluation and thorough family history taking for the diagnostic work-up of chorea]. / Het diagnostisch proces bij chorea: het belang van heroverwegen en de familieanamnese.

The differential diagnosis of chorea encompasses a broad range of disorders. In psychiatry, tardive dyskinesia may be difficult to discern from other causes, particularly when the family history is negative. A 59-year-old man with an unclear medical history had been using risperidone for over a decade when we first saw him. He presented with severe dyskinesia in all extremities. The family history for neuropsychiatric disorders was negative. We interpreted the movement disorder as tardive dyskinesia, but later he turned out to suffer from Huntington’s disease. To improve diagnostic accuracy, we should have more frequently re-evaluated the differential diagnosis and our family history should have been more thorough. We outline the diagnostic considerations in patients presenting with chorea. Finally, we highlight the value of diagnostic re-evaluation and thorough family history taking to optimize diagnostic accuracy in neuropsychiatry.

Chorea as an initial and solitary manifestation of systemic lupus erythematosus with antiphospholipid syndrome in an elderly man.

Chorea can be an initial manifestation of systemic lupus erythematosus (SLE) or antiphospholipid syndrome (APS). It has been mostly described in younger female adults in association with other manifestations of SLE. When chorea appears as an initial and only manifestation in SLE/APS patients, the establishment of the correct diagnosis is difficult, and it may be initially attributed to a more common aetiology. Here we report an elderly man who presented with a new onset of right-sided chorea without other clinical manifestations of SLE/APS. He started on steroids a year later, however, there was no improvement. His chorea was symptomatically managed along with aspirin, and hydroxychloroquine as he refused to be on additional immunosuppression. Anticoagulation was relatively contraindicated, and also not favoured by this patient; therefore, aspirin was initiated. Even in elderly patients, once the common etiologies of chorea have been worked up, we suggest doing a rheumatological evaluation. Early diagnosis and prompt treatment can prevent persistent neurological abnormality.

Recurrent hemichorea in an adolescent with systemic lupus erythematosus and previous ipsilateral cerebral infarction.

Systemic lupus erythematosus (SLE) can present with movement disorders, among which chorea is closely associated with antiphospholipid (aPL) antibodies. Brain imaging results obtained in patients with chorea are generally inconsistent with the clinical manifestation of chorea; moreover, medical tests for hemichorea, which are expected to reveal distinct localization, may show negative findings. Herein, we present a case of a 15-year-old girl with SLE who had a history of left cerebral infarction; tests revealed elevated aPL levels, and she developed recurrent left hemichorea 2 years later. Brain magnetic resonance imaging (MRI) results revealed no acute lesions during each episode of involuntary movements, and an MRI perfusion scan failed to provide an explanation for the asymmetric presentation. Although various hypotheses have been proposed regarding the mechanism underlying the occurrence of chorea, some scenarios still remain unexplained. Further investigation on the pathophysiology of chorea in SLE may be warranted to clarify its prognosis.

Chorea and polycythaemia vera.

We report two patients with chorea associated with polycythaemia vera, in whom the haematocrit and haemoglobin were within the reference range. Polycythaemia vera is potentially easily treatable and so is important to consider in people developing late-onset chorea.