Chorea and related movement disorders of paraneoplastic origin: the PNS EuroNetwork experience

Recent advances in non-Huntington's disease choreas

INTRODUCTION

Chorea is primarily due to an imbalance of basal ganglia output pathways, often due to dysfunction or degeneration of the caudate nucleus and putamen, and can be due to many causes.

METHODS

We reviewed the recent literature to identify newly-recognized causes of chorea, including auto-immune, metabolic, and genetic. We also focused upon developments in mechanisms relating to underlying pathophysiology of certain genetic choreas and advances in therapeutics.

RESULTS

Novel autoantibodies continue to be identified as causes of chorea. Both COVID-19 infection and vaccination are reported to result rarely in chorea, although in some cases causality is not clearly established. Advances in genetic testing continue to find more causes of chorea, and to expand the phenotype of known genetic disorders. Deep brain stimulation can be successful in certain circumstances.

CONCLUSION

Our understanding of mechanisms underlying this movement disorder continues to advance, however much remains to be elucidated.

Lung Cancer Wherein Durvalumab Induced Both Anti-CRMP-5 Antibody-related Paraneoplastic Neurological Syndromes and Neurological Adverse Events

A 68-year-old man with small-cell lung cancer developed anti-collapsin response-mediator protein (CRMP)-5 antibody-related paraneoplastic neurological syndrome (PNS) presenting with ataxia and chorea during treatment with durvalumab. As a result of steroid therapy, anti-CRMP-5 antibodies became negative, hyperintense lesions on brain magnetic resonance imaging disappeared, and neurological symptoms improved. After resuming durvalumab, he became unable to walk due to neurological adverse events (nAEs). There have been no reported cases manifesting PNSs and nAEs as a result of the same immune checkpoint inhibitors (ICIs) administered at different times. Resuming ICIs in patients diagnosed with PNSs should be performed with prudence.

Acute Hemichorea in an Elderly Patient With Positive Anti-centromere Antibodies and Lung Tumor

Though rare, autoimmune paraneoplastic and non-paraneoplastic chorea can be leading causes of adult-onset acute/subacute chorea. Here, we report a case of acute-onset chorea with suspected autoimmune-mediated mechanisms in a 79-year-old female who exhibited acute-onset choreiform movements on the right side of her body. She tested positive for anti-centromere antibodies (ACAs) without displaying symptoms of scleroderma. Blood sugar levels, genetic testing for Huntington's disease, and an antibody panel related to paraneoplastic neurological syndrome were unremarkable. Brain magnetic resonance imaging revealed no significant abnormalities. Computed tomography (CT) identified an irregularly shaped nodule in the middle lobe of the right lung. An 18F-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET)-CT scan showed an accumulation of radioactivity in the nodule and slight hypermetabolism in the striatum of both hemispheres. Her choreiform movements almost disappeared with a low dose of tiapride alone, without the need for anti-tumor therapy or immunotherapy. In cases of adult-onset acute/subacute chorea, investigating neoplasms and autoimmune diseases as underlying conditions is recommended. Tiapride, due to its good tolerability, is a valuable symptomatic therapy for elderly patients presenting with chorea, even in cases driven by autoimmune mechanisms.

Paraneoplastic movement disorders

Paraneoplastic movement disorders are diverse autoimmune neurological illnesses occurring in the context of systemic cancer, either in isolation or as part of a multifocal neurological disease. Movement phenomena may be ataxic, hypokinetic (parkinsonian), or hyperkinetic (myoclonus, chorea, or other dyskinetic disorders). Some disorders mimic neurodegenerative or hereditary illnesses. The subacute onset and coexisting nonclassic features of paraneoplastic disorders aid distinction. Paraneoplastic autoantibodies provide further information regarding differentiating cancer association, disease course, and treatment responses. A woman with cerebellar ataxia could have metabotropic glutamate receptor 1 autoimmunity, in the setting of Hodgkin lymphoma, a mild neurological phenotype and response to immunotherapy. A different woman, also with cerebellar ataxia, could have Purkinje cytoplasmic antibody type 1 (anti-Yo), accompanying ovarian adenocarcinoma, a rapidly progressive phenotype and persistent disabling deficits despite immune therapy. The list of antibody biomarkers is growing year-on-year, each with its own ideal specimen type for detection (serum or CSF), accompanying neurological manifestations, cancer association, treatment response, and prognosis. Therefore, a profile-based approach to screening both serum and CSF is recommended. Immune therapy trials are generally undertaken, and include one or more of corticosteroids, IVIg, plasma exchange, rituximab, or cyclophosphamide. Symptomatic therapies can also be employed for hyperkinetic disorders.

Hematologic malignancies and hematopoietic stem cell transplantation

Paraneoplastic neurologic syndromes are rarely associated with hematologic malignancies. In their rarity, lymphomas are the diseases with more frequent paraneoplastic neurologic syndrome. High-risk antibodies are absent in most lymphoma-associated paraneoplastic neurologic syndromes, with the exception of antibodies to Tr/DNER in paraneoplastic cerebellar degeneration, mGluR5 in limbic encephalitis, and mGluR1 in some cerebellar ataxias. Peripheral nervous system paraneoplastic neurologic syndromes are rare and heterogeneous, with a prevalence of demyelinating polyradiculoneuropathy in non-Hodgkin lymphoma. Polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes (POEMS) is a rare, paraneoplastic syndrome due to an underlying plasma cell disorder. The diagnosis is based on defined criteria, and vascular endothelial growth factor (VEGF), not an antibody, is considered a reliable diagnostic marker that also mirrors therapy response. As with the paraneoplastic neurologic syndromes in solid tumors, therapies rely on cancer treatment associated with immunomodulatory treatment with better response in PNS with antibodies to surface antigens. The best outcome is generally present in Ophelia syndrome/limbic encephalitis with anti-mGluR5 antibodies, with frequent complete recovery. Besides patients with isolated osteosclerotic lesions (where radiotherapy is indicated), hematopoietic stem-cell transplantation is the therapy of choice in patients with POEMS syndrome. In the paraneoplastic neurologic syndromes secondary to immune checkpoint inhibitors, discontinuation of the drug together with immunomodulatory treatment is recommended.

An overview on CV2/CRMP5 antibody-associated paraneoplastic neurological syndromes

Paraneoplastic neurological syndrome refers to certain malignant tumors that have affected the distant nervous system and caused corresponding dysfunction in the absence of tumor metastasis. Patients with this syndrome produce multiple antibodies, each targeting a different antigen and causing different symptoms and signs. The CV2/collapsin response mediator protein 5 (CRMP5) antibody is a major antibody of this type. It damages the nervous system, which often manifests as limbic encephalitis, chorea, ocular manifestation, cerebellar ataxia, myelopathy, and peripheral neuropathy. Detecting CV2/CRMP5 antibody is crucial for the clinical diagnosis of paraneoplastic neurological syndrome, and anti-tumor and immunological therapies can help to alleviate symptoms and improve prognosis. However, because of the low incidence of this disease, few reports and no reviews have been published about it so far. This article intends to review the research on CV2/CRMP5 antibody-associated paraneoplastic neurological syndrome and summarize its clinical features to help clinicians comprehensively understand the disease. Additionally, this review discusses the current challenges that this disease poses, and the application prospects of new detection and diagnostic techniques in the field of paraneoplastic neurological syndrome, including CV2/CRMP5-associated paraneoplastic neurological syndrome, in recent years.

Diagnostic Uncertainties: Chorea

Chorea is a hyperkinetic movement disorder with a multitude of potential etiologies, both acquired and inherited. Although the differential diagnosis for new-onset chorea is extensive, there are often clues in the history, exam, and basic testing that can help to narrow the options. Evaluation for treatable or reversible causes should take priority, as rapid diagnosis can lead to more favorable outcomes. While Huntington's disease is most common genetic cause of chorea, multiple phenocopies also exist and should be considered if Huntington gene testing is negative. The decision of what additional genetic testing to pursue should be based on both clinical and epidemiological factors. The following review provides an overview of the many possible etiologies as well as a practical approach for a patient presenting with new-onset chorea.

Case Report: Presence of Anti-MAG in the CSF Can Be Associated With a Neurodegenerative Process With Frontal Involvement

Background

Autoimmune encephalitis (AIE) is an increasingly broad nosological framework that may clinically mimic neurodegenerative diseases (NDDs).

Cases Reported

We describe here the clinical, radiological, electrophysiological, and biological evolution of three patients. Two women aged 73 and 72 years and a 69-year-old man presented with complex cognitive and focal neurological symptoms and each had a predominant frontal dysexecutive involvement and an unexpectedly high titer of anti-MAG antibodies in the serum and cerebrospinal fluid (CSF). The question of an autoimmune cause was raised. After 2 years of follow-up and, for two of them, without improvement despite immunosuppressive treatments, diagnoses of NDD were eventually retained: post-radiation encephalopathy, progressive supranuclear palsy (PSP), and Alzheimer's disease.

Conclusion

The presence of a high titer of anti-MAG antibodies may be found in NDD. It could reflect cerebral tissue damages, particularly in the case of significant frontal involvement. Atypical presentations may lead to a search for a paraneoplastic neurologic syndrome or AIE. However, the indirect immunofluorescence staining positivity on a monkey cerebellum section linked with anti-MAG antibodies should not lead to those diagnoses being retained.

Autoimmune and Paraneoplastic Chorea: A Review of the Literature

Autoimmune chorea syndromes represent a vast array of paraneoplastic, parainfectious and idiopathic disorders. It is increasingly apparent that familiarity with these disorders is critically important, as they may be treatable or may be part of a syndrome requiring further work-up and monitoring. These disorders are mediated by an aberrant immunologic attack with resultant neuronal dysfunction, manifesting as chorea. These conditions are typically accompanied by other neurologic or systemic manifestations. In this review we outline the clinical features, epidemiologic factors, and delineate the specific antibodies associated with each of these autoimmune mediated disorders. We highlight up to date information regarding this heterogeneous group of disorders, including a discussion of parainfectious Sydenham's chorea; paraneoplastic syndromes associated with CRMP-5 (collapsin response mediated protein-5/CV2) and ANNA-1 (antineuronal nuclear antibody / Hu) antibodies, in addition to neuronal antibody-associated disorders including anti-NMDAR, LGI1 (leucine-rich glioma inactivated-1) and CASPR2 (contactin associated protein-2). We discuss the more recently described entities of IgLON5, which has evidence of both immunologic and degenerative pathophysiology, in addition to PDE-10A antibody-associated chorea. We also outline chorea secondary to systemic diseases including Systemic Lupus Erythematosus (SLE) and Primary Antiphospholipid Syndrome (PAPS). We provide a framework for diagnosis and treatment.

Treatable Hyperkinetic Movement Disorders Not to Be Missed

Hyperkinetic movement disorders are characterized by the presence of abnormal involuntary movements, comprising most notably dystonia, chorea, myoclonus, and tremor. Possible causes are numerous, including autoimmune disorders, infections of the central nervous system, metabolic disturbances, genetic diseases, drug-related causes and functional disorders, making the diagnostic process difficult for clinicians. Some diagnoses may be delayed without serious consequences, but diagnosis delays may prove detrimental in treatable disorders, ranging from functional disabilities, as in dopa-responsive dystonia, to death, as in Whipple's disease. In this review, we focus on treatable disorders that may present with prominent hyperkinetic movement disorders.

Spontaneous Regression of Small Cell Lung Carcinoma and Associated Hemichorea

The spontaneous regression (SR) of cancer is defined as either partial or complete, and temporary or permanent, disappearance without appropriate treatment for the disease, and this phenomenon is rare in the case of small cell lung carcinoma (SCLC). We herein report an 83-year-old woman who presented with left-sided hemichorea associated with anti-SOX1 (SOX1-Ab) and -CV2/CRMP5 (CV2/CRMP5-Ab) antibodies with SR following a 7-year interval free of disease progression of SCLC. Hemichorea can present with the coexistence of anti-SOX1 and CV2/CRMP5-Ab with SR after a long interval free of SCLC. The immune response associated with these onco-neural antibodies may become independent of the original tumor trigger and remain active for many years.

Frequency and Characterization of Movement Disorders in Anti-IgLON5 Disease

BACKGROUND AND OBJECTIVES

Anti-IgLON5 disease is a recently described neurologic disease that shares features of autoimmunity and neurodegeneration. Abnormal movements appear to be frequent and important but have not been characterized and are underreported. We describe the frequency and types of movement disorders in a series of consecutive patients with this disease.

METHODS

In this retrospective, observational study, the presence and phenomenology of movement disorders were assessed with a standardized clinical questionnaire. Available videos were centrally reviewed by 3 experts in movement disorders.

RESULTS

Seventy-two patients were included. In 41 (57%), the main reason for initial consultation was difficulty walking along with one or several concurrent movement disorders. At the time of anti-IgLON5 diagnosis, 63 (87%) patients had at least 1 movement disorder with a median of 3 per patient. The most frequent abnormal movements were gait and balance disturbances (52 patients [72%]), chorea (24 [33%]), bradykinesia (20 [28%]), dystonia (19 [26%]), abnormal body postures or rigidity (18 [25%]), and tremor (15 [21%]). Other hyperkinetic movements (myoclonus, akathisia, myorhythmia, myokymia, or abdominal dyskinesias) occurred in 26 (36%) patients. The craniofacial region was one of the most frequently affected by multiple concurrent movement disorders (23 patients [32%]) including dystonia (13), myorhythmia (6), chorea (4), or myokymia (4). Considering any body region, the most frequent combination of multiple movement disorders consisted of gait instability or ataxia associated with craniofacial dyskinesias or generalized chorea observed in 31 (43%) patients. In addition to abnormal movements, 87% of patients had sleep alterations, 74% bulbar dysfunction, and 53% cognitive impairment. Fifty-five (76%) patients were treated with immunotherapy, resulting in important and sustained improvement of the movement disorders in only 7 (13%) cases.

DISCUSSION

Movement disorders are a frequent and leading cause of initial neurologic consultation in patients with anti-IgLON5 disease. Although multiple types of abnormal movements can occur, the most prevalent are disorders of gait, generalized chorea, and dystonia and other dyskinesias that frequently affect craniofacial muscles. Overall, anti-IgLON5 disease should be considered in patients with multiple movement disorders, particularly if they occur in association with sleep alterations, bulbar dysfunction, or cognitive impairment.

Nodal Peripheral T-cell Lymphoma with T Follicular Helper Phenotype Presenting as Chorea During Treatment: A Case Report and Literature Review

A 72-year-old man presented with chorea while undergoing treatment for recurrence of nodal peripheral T-cell lymphoma with T follicular helper (TFH) phenotype. An examination by brain N-isopropyl-p-iodoamphetamine (123I-IMP)-single photon emission computed tomography (SPECT) revealed no abnormalities other than a decreased cerebral blood flow (CBF) in the left striatum. After four courses of salvage chemotherapy, his clinical symptoms and asymmetric cerebral perfusion improved, suggesting that the decreased CBF had caused chorea. The significance of brain SPECT has not been fully clarified in patients with chorea-associated malignant lymphoma, warranting further investigations. Brain SPECT is an alternative approach to identify abnormalities in such patients.

A Longitudinal, Observational Analysis of Neuronal Injury Biomarkers in a Case Report of a Patient With Paraneoplastic Anti-CRMP5 Antibody-Associated Transverse Myelitis

Biomarkers are needed to guide therapeutic decision making in autoimmune and paraneoplastic neurologic disorders. Here, we describe a case of paraneoplastic collapsing response-mediator protein-5 (CRMP5)-associated transverse myelitis (TM) where plasma neurofilament light (NfL) chain and glial fibrillary protein (GFAP) levels were observed over a 14-month clinical course, correlating with radiographical and clinical outcome measures in response to treatment. Blood and CSF samples obtained at diagnosis as well as 7 and 14 months into treatment. At the time of initial diagnosis, both plasma NfL (782.62 pg/ml) and GFAP (283.26 pg/ml) were significantly elevated. Initial treatment was with IV steroids and plasma exchange (PLEX) followed by neuroendocrine tumor removal, chemotherapy, and radiation. After initial improvement with chemotherapy, the patient experienced clinical worsening and transient elevation of plasma NfL (103.27 pg/ml and GFAP (211.58 pg/ml) levels. Whole body positron emission tomography PET scan did not demonstrate recurrence of malignancy. Repeat PLEX and rituximab induction resulted in improvements in patient function, neurologic exam, and plasma biomarker levels. To our knowledge, this is the first described longitudinal, prospective analysis of neuronal injury biomarkers and association of clinical treatment outcomes in CRMP5 myelitis. Our findings suggest that clinical improvement correlates with NfL and GFAP concentrations.

Movement Disorders and Hematologic Diseases

Background

Movement disorders can be associated with or caused by hematological abnormalities. The objective of this review is to highlight features that will aid in the clinician's recognition and treatment of these disorders.

Methods

MESH terms relevant to movement disorders and hematologic diseases were searched to identify conditions included in this narrative, educational review.

Results

Several conditions were identified, and they were organized by hematologic categories to include red blood cell abnormalities, white blood cell abnormalities, disorders of clotting and bleeding, hematologic malignancies, and others.

Conclusions

This review will increase providers' understanding of disorders that include movement disorders and hematologic abnormalities. Basic hematologic laboratories can aid in assessment of these disorders, to include complete blood count/hemogram and peripheral blood smear. Recognition is key, especially in the setting of underlying malignancy, vitamin deficiency, or other disorder in which treatment is available.

Hemichorea-hemiballismus as the initial manifestation of symptomatic middle cerebral artery dissection: A case report

INTRODUCTION

Hemichorea-hemiballismus, which spans a spectrum of involuntary, continuous, nonpatterned movement involving one side of the body, can emerge as the initial manifestation of acute ischemic stroke. However, because of its rarity in the community, the diagnosis and treatment are often delayed.

PATIENT CONCERNS

We report a unique case of a 47-year-old female who presented with acute onset hemichorea-hemiballismus. No obvious focal sign apart from involuntary, continuous, nonpatterned movement of her left arm and leg was presented.

DIAGNOSIS

Initial diffusion-weighted magnetic resonance imaging (MRI) was negative but significant increase of blood flow velocity in the right middle cerebral artery (MCA) stem was revealed by transcranial doppler sonography. Repeated MRI showed acute infarction in the contralateral globus pallidus. Isolated dissection of the right MCA typified by intimal flap with double lumen was identified by digital subtraction angiography and high-resolution magnetic resonance imaging (HR-MRI).

INTERVENTIONS

The patient was initially treated with dual antiplatelet agents but the uncontrollable movement deteriorated during hospitalization. Antithrombotic therapy was then intensified with combination of tirofiban and low-molecular-weight heparin. Other symptomatic treatment included volume expansion with colloidal fluid to improve cerebral perfusion. Her involuntary movement gradually diminished and the patient was discharged with rivaroxaban 15 mg/daily.

OUTCOMES

The patient had recovered with significant reduction in her hemichorea-hemiballismus. Three-month follow-up HR-MRI showed complete resolution of the MCA dissection lesions.

CONCLUSION

Prompt recognition of acute onset hemichorea-hemiballismus as the manifestation of acute ischemic stroke in appropriate clinical setting may reduce diagnostic delay. Multiple imaging techniques including cerebral digital subtraction angiography and HR-MRI can be applied to diagnosis and further clarify the mechanism of stroke, which facilitate in selection of secondary prevention therapies.

Guillain-Barre Syndrome and Syndrome of Inappropriate Antidiuretic Hormone (SIADH) Secretion as Paraneoplastic Syndromes in Splenic Marginal B-cell Non-Hodgkins Lymphoma: A Rare Presentation

Splenic marginal zone lymphoma (SMZL), a rare sub-type of non-Hodgkin lymphoma (NHL) presents with abdominal discomfort, lymphocytosis, cytopenias along with B symptoms including fatigue, night sweats, night fevers, weight loss. NHLs rarely present with paraneoplastic neurological syndromes like Guillain-Barre (GB) syndrome, myelopathy causing paraplegia, chorea, neuromyotonia, vasculitic neuropathy and dermatomyositis. Here, we present a 85-year old caucasian lady presenting with GB syndrome and Syndrome of Inappropriate Antidiuretic Hormone (SIADH) who eventually got diagnosed with SMZL.

Review of Hereditary and Acquired Rare Choreas

Background:

Movement disorders are often a prominent part of the phenotype of many neurologic rare diseases. In order to promote awareness and diagnosis of these rare diseases, the International Parkinson’s and Movement Disorders Society Rare Movement Disorders Study Group provides updates on rare movement disorders.

Methods:

In this narrative review, we discuss the differential diagnosis of the rare disorders that can cause chorea.

Results:

Although the most common causes of chorea are hereditary, it is critical to identify acquired or symptomatic choreas since these are potentially treatable conditions. Disorders of metabolism and mitochondrial cytopathies can also be associated with chorea.

Discussion:

The present review discusses clues to the diagnosis of chorea of various etiologies. Authors propose algorithms to help the clinician in the diagnosis of these rare disorders.

Antibody-related movement disorders - a comprehensive review of phenotype-autoantibody correlations and a guide to testing

Background

Over the past decade increasing scientific progress in the field of autoantibody-mediated neurological diseases was achieved. Movement disorders are a frequent and often prominent feature in such diseases which are potentially treatable.

Main body

Antibody-mediated movement disorders encompass a large clinical spectrum of diverse neurologic disorders occurring either in isolation or accompanying more complex autoimmune encephalopathic diseases. Since autoimmune movement disorders can easily be misdiagnosed as neurodegenerative or metabolic conditions, appropriate immunotherapy can be delayed or even missed. Recognition of typical clinical patterns is important to reach the correct diagnosis.

Conclusion

There is a growing number of newly discovered antibodies which can cause movement disorders. Several antibodies can cause distinctive phenotypes of movement disorders which are important to be aware of. Early diagnosis is important because immunotherapy can result in major improvement.In this review article we summarize the current knowledge of autoimmune movement disorders from a point of view focused on clinical syndromes. We discuss associated clinical phenomenology and antineuronal antibodies together with alternative etiologies with the aim of providing a diagnostic framework for clinicians considering underlying autoimmunity in patients with movement disorders.

Comparisons Between Infectious and Autoimmune Encephalitis: Clinical Signs, Biochemistry, Blood Counts, and Imaging Findings

OBJECTIVE

Infectious encephalitis (IE) and autoimmune encephalitis (AE) are symptomatically similar in clinic, however essentially different in pathogenesis. Therefore, the objective of this study was to identify specific features to distinguish the two types of encephalitis for early effective diagnosis and treatments through a comparative analysis.

METHODS

Fifty-nine IE patients and 36 AE patients were enrolled. The patients with IE were divided into viral encephalitis (VE) and bacterial encephalitis (BE) according to the pathogens in cerebrospinal fluid (CSF). Patients with AE were categorized by with or without neural autoantibodies (NAAb). We further divided patients with NAAb into those with neural cell-surface antibodies (NSAbs) or intracellular antibodies (Abs). Clinical features, laboratory data, and imaging findings were compared between AE, IE, and subgroups.

RESULTS

Memory deficits, involuntary movement, and seizures were relatively more commonly presenting symptoms in AE patients (p < 0.05). The positive rate of Pandy test was higher in IE patients (p = 0.007). Decreased leukocyte, erythrocyte, and platelet counts in blood were found in IE patients (p < 0.05). Lower serum calcium level was found in VE compared to BE (p = 0.027). Meanwhile, higher serum calcium level was found in patients with NSAbs compared with intracellular Abs (p = 0.034). However, higher levels of LDH in CSF were found in patients with intracellular Abs (p = 0.009). In magnetic resonance imaging, hippocampus lesions were more commonly present in patients with AE (p = 0.042). Compared with AE patients, more IE patients displayed the background electroencephalogram rhythm of slow-frequency delta (p = 0.013).

CONCLUSION

Involuntary movement and memory deficits were more specifically present in AE patients. CSF Pandy, blood routine test and hippocampus lesions detections were potential markers for distinguishing AE and IE. Further, CSF LDH, and serum calcium levels were potentially useful to distinguish subgroups of encephalitis.

Anti-CV2/CRMP5 Paraneoplastic Chorea Effectively Managed with Intravenous Amantadine

BACKGROUND

Paraneoplastic chorea is typically a subacute progressive hyperkinetic movement disorder. The mainstay of treatment is managing the underlying neoplasm. However, the clinical course may be variable, and effective symptomatic management can precede the start of cancer treatment.

CASE REPORT

A 63-year-old man presented with insidious onset, slowly progressive generalized chorea for 1 year, later diagnosed as anti-CV2/CRMP5 autoantibody positive paraneoplastic chorea. His chorea was markedly improved with intravenous amantadine.

DISCUSSION

In patients with anti-CV2/CRMP5 autoantibody-related chorea, sequential follow-up of brain magnetic resonance imaging reveals progression from active inflammation to atrophy. Our report highlights the efficacy of intravenous amantadine in paraneoplastic chorea.

Paraneoplastic movement disorders: phenomenology, diagnosis, and treatment

Paraneoplastic syndromes include, by definition, any symptomatic and non-metastatic condition associated with a neoplasm. Paraneoplastic movement disorders are a heterogeneous group of syndromes encompassing both hyperkinetic and hypokinetic conditions, characterized by acute/sub-acute onset, rapidly progressive evolution, and multifocal localizations with several overlapping features. These movement disorders are immune-mediated, as shown by the rapid onset and by the presence of antineuronal antibodies in biological samples of patients, fundamental for the diagnosis. Antineuronal antibodies could be targeted against intracellular or neuronal surface antigens. Paraneoplastic movement disorders associated with anti-neuronal surface antigens antibodies respond more frequently to immunotherapy. The underlying tumors may be different, according to the clinical presentation, age, and gender of patients. Our search considered articles involving human subjects indexed in PubMed. Abstracts were independently reviewed for eligibility criteria by one author and validated by at least one additional author. In this review, we sought to critically reappraise the clinical features and the pathophysiological mechanisms of paraneoplastic movement disorders, focusing on diagnostic and therapeutic strategies. Our main aim is to make clinicians aware of paraneoplastic movement disorders, and to provide assistance in the early diagnosis and management of these rare but life-threatening conditions.

Movement disorders associated with neuronal antibodies

Movement disorders are one of the common clinical features of neurological disease associated with neuronal antibodies which is a group of potentially reversible disorder. They can present with hypokinetic or hyperkinetic types of involuntary movements and may have other associated neurological symptoms. The spectrum of abnormal movements associated with neuronal antibodies is widening. Some specific phenomenology of movement disorders are likely to give clue about the type of antibody, for instance, presence of paroxysmal dystonia (facio-brachial dystonic seizures) are a pointer toward presence of LGI-1 antibodies, and orofacial lingual dyskinesia is associated with NMDAR associated encephalitis. The presence of specific type of movement disorder allows high suspicion of testing of certain specific type of antibodies. In this review, we have discussed the various antibodies and the spectrum of movement disorder associated with them, highlighting if any distinct movement disorder allows the clinician to suspect type of antibody in a certain clinical context. We have also reviewed the treatment of the movement disorder associated with the neuronal antibodies. Physicians should have high index of suspicion of these disorders, as early institution of treatment options can lead to better outcome.

[A case of hemichorea associated with lung adenocarcinoma]

An 81-year-old woman admitted to our hospital due to involuntary movement on her right extremities. Laboratory tests, including autoantibodies, were unremarkable and only age related changes were observed on brain MRI. Chest CT revealed lung adenocarcinoma. She was diagnosed as having paraneoplastic chorea. After removal of the tumor, her chorea was dramatically improved. One year after the operation, abnormal high intensity lesions were seen in bilateral caudate nuclei and globus pallidus on MRI. A part of the left caudate nucleus was enhanced by gadolinium. Here we show a clinical picture and neuroradiological findings of paraneoplastic chorea associated with lung adenocarcinoma.

Paraneoplastic movement disorders

Paraneoplastic movement disorders are rare, autoimmune-mediated, nonmetastatic complications of malignant neoplasms. Common paraneoplastic movement disorders include paraneoplastic chorea, dystonia, cerebellar degeneration, different types of encephalitis, opsoclonus-myoclonus syndrome, stiff person syndrome, and neuromyotonia. Syndromes usually develop before tumor diagnosis, have subacute onset, and are associated with serum or cerebrospinal fluid antibodies. Two types of antibodies can be distinguished: antibodies against nuclear and cytoplasmic neuronal antigens (anti-Hu, anti-Ri, anti-Yo, anti-Ma, anti-CV2/CRMP5, anti-Gephrin, and anti-GABATRAP) and antibodies recently identified against cell surface and synaptic proteins (anti-NMDAR, anti-LGI1, and anti-Caspr2). These two types differ from each other in a few important aspects. Antibodies against cell surface and synaptic protein disrupt cell-surface antigens. Clinical symptoms are related to the disruption of antigens and potentially can be reversed by immunotherapy. The association between these antibodies and malignancy is much less consistent. On the other hand, antibodies against nuclear and cytoplasmic neuronal antigens seem to be not pathogenic; however, they most likely indicate a T-cell-mediated immune response against neurons. Due to T-cell-mediated neuronal loss, response to immunotherapy is generally disappointing. Early recognition of all these diseases is crucial because it may lead to the disclosure of occult cancer. This review is focused on paraneoplastic movement disorders with emphasis on clinical presentations, investigational findings, and therapeutic results.

Movement disorders with neuronal antibodies: syndromic approach, genetic parallels and pathophysiology

Movement disorders are a prominent and common feature in many autoantibody-associated neurological diseases, a group of potentially treatable conditions that can mimic infectious, metabolic or neurodegenerative disease. Certain movement disorders are likely to associate with certain autoantibodies; for example, the characteristic dyskinesias, chorea and dystonia associated with NMDAR antibodies, stiff person spectrum disorders with GAD, glycine receptor, amphiphysin or DPPX antibodies, specific paroxysmal dystonias with LGI1 antibodies, and cerebellar ataxia with various anti-neuronal antibodies. There are also less-recognized movement disorder presentations of antibody-related disease, and a considerable overlap between the clinical phenotypes and the associated antibody spectra. In this review, we first describe the antibodies associated with each syndrome, highlight distinctive clinical or radiological 'red flags', and suggest a syndromic approach based on the predominant movement disorder presentation, age, and associated features. We then examine the underlying immunopathophysiology, which may guide treatment decisions in these neuroimmunological disorders, and highlight the exceptional interface between neuronal antibodies and neurodegeneration, such as the tauopathy associated with IgLON5 antibodies. Moreover, we elaborate the emerging pathophysiological parallels between genetic movement disorders and immunological conditions, with proteins being either affected by mutations or targeted by autoantibodies. Hereditary hyperekplexia, for example, is caused by mutations of the alpha subunit of the glycine receptor leading to an infantile-onset disorder with exaggerated startle and stiffness, whereas antibodies targeting glycine receptors can induce acquired hyperekplexia. The spectrum of such immunological and genetic analogies also includes cerebellar ataxias and some encephalopathies. Lastly, we discuss how these pathophysiological considerations could reflect on possible future directions regarding antigen-specific immunotherapies or targeting the pathophysiological cascades downstream of the antibody effects.

Autoimmune and paraneoplastic movement disorders: An update

Movement disorders (MDs) are common in patients with autoimmune disorders affecting the central and peripheral nervous system. They may be observed in autoimmune disorders triggered by an infectious agent, such as streptococcus in Sydenham's chorea, or in basal ganglia encephalitis with antibodies against the dopamine-D2 receptors. In these patients chorea or dystonia are usually the most prominent hyperkinetic MDs. MDs are also observed in patients with diffuse or limbic encephalitis with antibodies directed against neuronal cell-surface antigens. Anti-NMDA receptor encephalitis is one of the most common and may present with a variety of MDs, including: chorea, stereotypies, dystonia and myorhythmia. The recognition of other abnormal motor phenomena such as "faciobrachial dystonic seizures" and neuromyotonia, observed in patients with LGI1 and Caspr-2 antibodies, is important because they may herald the onset of overt limbic encephalitis. Autoimmunity directed against the intracellular enzyme glutamic acid decarboxylase usually presents with MDs, most commonly stiff-person syndrome or cerebellar ataxia. Chorea may be observed in rheumatologic disorders such as systemic lupus erythematosus or antiphospholipid syndrome. Disorders with uncertain autoimmune mechanisms such as Hashimoto's encephalitis and idiopathic opsoclonus-myoclonus syndrome commonly present with tremor, myoclonus and ataxia. A rapid diagnosis of an autoimmune disorder, which typically presents with subacute onset, is critical as early therapeutic intervention improves long-term prognosis and may be life-saving. Treatment usually involves some form of immunotherapy and symptomatic therapy of the abnormal movements with dopamine depleters, dopamine receptor antagonists, or GABAergic drugs. Detection and removal of an underlying tumor is essential for optimal outcome.

Autoimmune choreas

Chorea, a movement disorder characterised by a continuous flow of unpredictable muscle contractions, has a myriad of genetic and non-genetic causes. Although autoimmune processes are rare aetiology of chorea, they are relevant both for researchers and clinicians. The aim of this article is to provide a review of the epidemiology, clinical and laboratory features, pathogenesis and management of the most common autoimmune causes of chorea. Emphasis is given particularly to Sydenham's chorea, systemic lupus erythematosus, primary antiphospolipid antibody syndrome, paraneoplastic chorea and anti-N-methyl-d-aspartate receptor encephalitis.

Anti-Yo, chorea and hemiballismus: A case report

68-year-old female presented with involuntary movements. MRI was normal. Cerebrospinal fluid analysis was normal. whole body CT and biopsy confirmed diagnosis of metastatic adenocarnimoa. The autoimmune panel was positive for anti-Yo antibodies.

Autoimmune paraneoplastic syndromes associated to lung cancer: A systematic review of the literature: Part 3: Neurological paraneoplastic syndromes, involving the central nervous system

The development of new immune treatment in oncology and particularly for lung cancer may induce new complications, particularly activation or reactivation of auto-immune diseases. In this context, a systematic review on the auto-immune paraneoplastic syndromes that can complicate lung cancer appears useful. This article is the third of a series of five and deals mainly with neurological paraneoplastic syndromes involving the central nervous system.

Anti-collapsin response mediator protein 5 encephalitis masquerading as a low-grade brain tumour

A 71-year-old woman presented acutely with seizures; her MRI suggested a low-grade glioma of the right temporal lobe. Over the preceding 18 months, she had developed progressive limb chorea and orofacial dyskinesia. Examination showed a predominantly amnestic cognitive profile. Initial investigations were normal, but later she was found to have antibodies to collapsin response mediator protein 5 (also called CV2). Her symptoms and neuroimaging abnormalities gradually improved without treatment. Four months later, surveillance imaging with (18)F-fluorodeoxyglucose-positron-emission tomography revealed a lesion confirmed by biopsy as a TX, N2, M0 small-cell lung cancer. This case is unusual for the strikingly unilateral neuroimaging abnormalities, which led to an initial misdiagnosis, and the spontaneous symptomatic improvement without treatment. In retrospect, the co-occurrence of paraneoplastic chorea, limbic encephalitis and neuropathy in the presence of an occult lung tumour make this almost a 'full house' of symptoms associated with antibodies to collapsin response mediator protein 5. It underlines the importance in clinical reasoning of avoiding the cognitive errors of premature closure and anchoring.

Autoimmune movement disorders

Autoimmune movement disorders encapsulate a large and diverse group of neurologic disorders occurring either in isolation or accompanying more diffuse autoimmune encephalitic illnesses. The full range of movement phenomena has been described and, as they often occur in adults, many of the presentations can mimic neurodegenerative disorders, such as Huntington disease. Disorders may be ataxic, hypokinetic (parkinsonism), or hyperkinetic (myoclonus, chorea, tics, and other dyskinetic disorders). The autoantibody targets are diverse and include neuronal surface proteins such as leucine-rich, glioma-inactivated 1 (LGI1) and glycine receptors, as well as antibodies (such as intracellular antigens) that are markers of a central nervous system process mediated by CD8+ cytotoxic T cells. However, there are two conditions, stiff-person syndrome (also known as stiff-man syndrome) and progressive encephalomyelitis with rigidity and myoclonus (PERM), that are always autoimmune movement disorders. In some instances (such as Purkinje cell cytoplasmic antibody-1 (PCA-1) autoimmunity), antibodies detected in serum and cerebrospinal fluid can be indicative of a paraneoplastic cause, and may direct the cancer search. In other instances (such as 65kDa isoform of glutamic acid decarboxylase (GAD65) autoimmunity), a paraneoplastic cause is very unlikely, and early treatment with immunotherapy may promote improvement or recovery. Here we describe the different types of movement disorder and the clinical features and antibodies associated with them, and discuss treatment.

A case of tardive dyskinesia in the last weeks of life

Tardive dyskinesia (TD) is a chronic and often irreversible movement disorder that usually evolves after years of neuroleptic use but can sometimes develop over a much shorter time frame. Paradoxically, a higher dose of the neuroleptic agent that causes TD can often temporarily suppress the movement disorder. This is generally an inadvisable approach, though, as its effectiveness is probably limited to only a matter of weeks and as it will worsen the problem in the long run. We describe a patient with widely metastatic squamous cell carcinoma of the lung who developed severe TD when treated with chlorpromazine for severe hiccups. As his prognosis was only days to weeks, we were able to effectively suppress his TD with haloperidol. Hospice care emphasizes relief of suffering at the end of life, often at the expense of attention to long-range adverse effects, and this approach may be a viable management strategy for patients with TD and very limited prognosis.

Chorea associated with high titers of antiphospholipid antibodies in the absence of antiphospholipid antibody syndrome

Background

Chorea associated with high titers of antiphospholipid antibodies in the absence of antiphospholipid antibody syndrome has been seldom reported.

Case report

An 89-year-old female developed persistent right side chorea associated with high titers of anticardiolipin antibody (antiphospholipid antibosies immunoglobulin (Ig)M, 45 MPL and 112 IgM aCL (MPL) after 3 months) but normal lupus anticoagulants. Her magnetic resonance imaging (MRI) showed no abnormality, but positron emission tomography (PET) demonstrated increased bilateral striatal metabolic activity, more on the left side. Her MRI showed no cause for chorea. The PET scan demonstrated a marked increase in the metabolic activity of the left basal ganglia.

Discussion

Her chorea remained unchanged over a 9-month follow-up period. The literature on chorea associated with high titers of antiphospholipid antibodies in the absence of antiphospholipid syndrome is reviewed.