Sydenham's Chorea Research Articles

Chorea in children: etiology, diagnostic approach and management.

Chorea is defined by the presence of abnormal, involuntary, continuous, random movements that results from a number of autoimmune, hereditary, vascular, metabolic, drug-induced and functional (psychogenic) causes. Chorea may present at all stages of life, from newborns to elderly individuals. While Huntington disease is the main suspicion in adults presenting with chorea, once a drug-induced or parkinsonian dyskinesia have been ruled out; Huntington disease exceptionally presents with chorea in children. Sydenham chorea is considered the most common cause of acute childhood-onset chorea, but its prevalence has decreased in Western countries. However, in younger children other etiologies such as dyskinetic cerebral palsy, anti-NMDAR receptor encephalitis, other autoimmune conditions, or mutations in NKX2-1, ADCY-5, FOXG1, GNAO1, GPR88, SLC2A1, SQSTM1, ATP8A2, or SYT-1 should be considered. In this manuscript, we review the main causes, diagnosis and management of chorea in children.

Bertolt Brecht. Did he really have rheumatic fever?

The writer Bertolt Brecht (1898-1956) is known for his poems, dramas and the "epic or dialectical theater" he founded. He was retrospectively postulated to have had rheumatic fever because of heart problems and neuromuscular symptoms in his youth. Based on current rheumatological knowledge, it cannot be deduced with certainty from the available documents that Brecht had rheumatic fever. At most, avery unusual manifestation of rheumatic fever can be suspected with atypical rheumatic chorea and avery atypical course of rheumatic carditis. Several deviations from the classical clinical picture-the absence of fever and arthritis, no typical symptoms of Sydenham's chorea, the lack of a diagnosis of heart valve defects in adolescence-lead to extensive differential diagnostic considerations. Apossible psychosomatic origin through functional heart complaints must even be postulated if atemporary previous organic cause cannot be excluded. Only the use of the advanced diagnostics available today with Doppler sonography of the heart, cardiac magnetic resonance imaging (MRI), throat swabs for Streptococci and streptococcal serology would have made it possible to diagnose Brecht's cardiac symptoms in his adolescence without adoubt and to differentiate them from functional heart complaints. His death is verified by medical documents clearly documenting bacterial endocarditis with evidence of coli bacteria caused by urological interventions with subsequent febrile episodes and pyelonephritis.

Acute rheumatic fever in south-east of Turkey: clinical features and epidemiological evaluation of the patients over the last 25 years.

This study evaluates clinical and epidemiological features of acute rheumatic fever using the data of last 25 years in our hospital in south-east of Turkey. The medical records of 377 patients with acute rheumatic fever admitted to Pediatric Cardiology Department of Çukurova University during 1993-2017 were retrospectively analysed. Two hundred and six patients were admitted between 1993 and 2000, 91 between 2001 and 2008, and 80 between 2009 and 2017. The largest age group (52%) were between 9 to 12 years of age and approximately two-thirds of the patients presented in the spring and winter seasons (62.8%). Among the major findings, the most common included carditis 83.6% (n = 315), arthritis at 74% (n = 279), Sydenham's chorea at 13.5% (n = 51), and only two patients (0.5%) had erythema marginatum and two patients (0.5%) had subcutaneous nodule. Carditis was the most common manifestation observed in 315 patients (83.6%). The most commonly affected valve was the mitral valve alone (54.9%), followed by a combined mitral and aortic valves (34%) and aortic valve alone (5.7%). Of the patients with carditis, 48.6% (n = 153) had mild carditis, of which 45 had a subclinical. Sixty-two patients (19.7%) had moderate and 100 patients (31.7%) had severe carditis. At the follow-up, 2 patients died and 16 patients underwent valve surgery. Twenty-eight (7.4%) patients' valve lesions were completely resolved. Conclusion: Although the incidence of acute rheumatic fever decreased, it still is an important disease that can cause serious increases in morbidity and mortality rates in our country.

Autoantibody Biomarkers for Basal Ganglia Encephalitis in Sydenham Chorea and Pediatric Autoimmune Neuropsychiatric Disorder Associated With Streptococcal Infections.

Movement, behavioral, and neuropsychiatric disorders in children have been linked to infections and a group of anti-neuronal autoantibodies, implying dopamine receptor-mediated encephalitis within the basal ganglia. The purpose of this study was to determine if anti-neuronal biomarkers, when used as a group, confirmed the acute disease in Sydenham chorea (SC) and pediatric autoimmune neuropsychiatric disorder associated with streptococcal infections (PANDAS). IgG autoantibodies against four neuronal autoantigens (tubulin, lysoganglioside GM1, and dopamine receptors D1 and D2) were detected in SC sera (N=8), sera and/or cerebrospinal fluid (CSF) from two groups of PANDAS cases (N=25 first group and N=35 second group), sera from Tourette's syndrome (N=18), obsessive-compulsive disorder (N=25), attention deficit hyperactivity disorder (N=18), and healthy controls (N=28) by direct enzyme-linked immunosorbent assay (ELISA). IgG specific for neuronal autoantigens was significantly elevated during the acute symptomatic phase, and the activity of calcium/calmodulin-dependent protein kinase II (CaMKII) pathway was significantly elevated in human neuronal cells. Five assays confirmed the disease in SC and in two groups of children with PANDAS. In 35 acute onset PANDAS patients, 32 sera (91.4%) were positive for one or more of the anti-neuronal autoantibodies compared with 9 of 28 healthy controls (32.1%, p<0.0001). Importantly, CSF of 32 (91.4%) PANDAS patients had one or more detectable anti-neuronal autoantibody titers and CaMKII activation. Among healthy control subjects with elevated serum autoantibody titers for individual antigens, none (0%) were positively associated with elevated positive CaMKII activation, which was a striking contrast to the sera of PANDAS subjects, who had 76–89% positive association with elevated individual autoantibody titers and positive CaMKII activity. At 6 months follow-up, symptoms improved for more than 80% of PANDAS subjects, and serum autoantibody titers also significantly decreased. Results reported herein and previously published studies in our laboratory suggest the antibody biomarkers may be a useful adjunct to clinical diagnosis of SC, PANDAS, and related disorders and are the first known group of autoantibodies detecting dopamine receptor-mediated encephalitis in children.

Sydenham chorea in a12- year old Saudi girl

Sydenham chorea (SC) is the most common acquired cause of chorea in children.(SC) is the neurological manifestation of rheumatic fever. Rheumatic fever is still reported in Saudi Arabia, although less frequently. According to modified Jones criteria, carditis and arthritis are the major manifestations of acute rheumatic fever (ARF) in children.SC is often seen in isolated form; however, it can occur in association with other clinical manifestations of ARF like carditis. It has been reported that silent, mild valvular regurgitation has been found in patients with pure chorea.SC is characterized by abnormal body movement, associated with behavioral changes. It is an autoimmune disease that occurs following an infection with Group A beta-haemolytic streptococcal infection that is prevalent in Saudi Arabia.Despite recent advances in child health care services, RF continues to occur in Saudi Arabia. We describe a 12-year-old Saudi girl with SC and clinically inaudible, but echocardiographically significant mild valvular regurgitation.The diagnosis of Sydenham chorea should be considered in young children with choreiform movements. Doppler echocardiography may be useful in detecting silent valvular regurgitation and in deciding the duration of penicillin prophylaxis.

Huntington's disease and Sydenham's chorea

Huntington's disease was an important example for discussing the problem of predictive genetic testing. Like other movement disorders, it includes non-motor symptoms and a prodromal phase. As a rapidly progressive monogenetic disease, it is an important model disease for the study of neurodegenerative pathomechanisms and one of the first movement disorders for which causal therapies seem to be reachable.

The Case Report: Chorea Sydenham In Young Adult Female As Symptom Of Rheumatic Fever

Abstract&#x0D; Background: Chorea Sydenham is an involuntary movement disorder due to an autoimmune process. But we must keep precaution that Sydenham chorea is part of rheumatic fever symptoms. Tthorough and complete examination is needed to create the right diagnose. This will support the success of therapy and prevent other complications.&#x0D; Case: 18-year-old woman was hospitalized with complaints of involuntary movement on the left side accompanied by fever, breathing problem, and nausea. Motoric weakness, tremor or other involuntary movement are not found. ASTO and CRP results were increased. The patient was consulted with cardiologist and has mild mitral regurgitation on echocardiograph. Those exams results are included in the criteria for diagnosing rheumatic fever and can be given the right therapy.&#x0D; Discussion: Chorea Sydenham can’t threaten patient’s life immediately. But if the examination and therapy are given incorrect, it will cause other severe complications. That is because Chorea Sydenham is part of autoimmune process which can cause other organs complication.&#x0D; Conclusion: Chorea Sydenham is one of the symptoms of rheumatic fever. So that a thorough and proper examination is needed to create early diagnosis. This will support the provision of therapy and accelerate the recovery of patients.

Kore Ön Tanılı Hastaların Değerlendirilmesi: Sydenham Koresi ve Ayırıcı Tanılar

Objective: Our aim is to evaluate patients being referred with an initial diagnosis of chorea according to their clinical, laboratory features and final diagnoses while emphasizing cardiological findings of patients with Sydenham chorea. Method: Children aged 4-18 years who were referred to Okmeydanı Research and Training Hospital Pediatric Neurology department with an initial diagnosis of acute, subacute chorea between January 2017-January 2020 were retrospectively included. Chronic chorea and diseases associated with chronic chorea were excluded from the study. Data concerning clinical, laboratory features, cardiological findings, etiologies, treatments, recurrence rates and follow-ups of patients were recorded. Descriptive statistical analysis were performed using SPSS 21.0. Results: Fifteen patients has been referred with the initial diagnosis of chorea. Mean age of the patients was 11.5±2.2 years. Ten (67%) patients were females, 5 (33%) patients were male. After admission, 8 (54%) patients were diagnosed with Sydenham chorea, and 2 (13%) patients with recurrent Sydenham chorea. During physical examination, 5 (33%) patients did not have chorea, and 3 cases had tic disorder. Out of 8 patients with new diagnosis of Sydenham chorea, 3 (37.5%) patients had subclinical carditis, and 5 (62.5%) patients clinical carditis. Chorea had been treated with one of haloperidol/biperiden, valproic acid and prednisolon options. The treatment of 6 patients attending regular follow-up visits was stopped 2-6 months later. Chorea of two patients recurred during our follow-up, and one of our newly diagnosed Sydenham chorea patients had been recognized as antiphospholipid antibody syndrome after recurrence. Conclusion: Sydenham chorea is the most common cause of acquired chorea in childhood. Most of the time it is self limiting. Differential diagnosis of chorea must be kept in mind especially when there is a recurrence.

Mapping of world publications: Sydenham chorea disease

The present paper focuses on Mapping of World Publications: Sydenham Chorea Disease. Which has given on PubMed database for during the year 2000 to 2018? There are total 9799 documents on Sydenham Chorea Disease. It discusses on ascertain the Sydenham chorea research of documents, ranking of most prolific authors, institution-wise distribution of publications. Concept mapping is a general method, it is particularly useful for helping social researchers and research teams develop and detail ideas for research and, it is especially valuable when researchers want to involve relevant stakeholder groups in the act of creating the research project. Although concept mapping is used for many purposes strategic planning, product development, market analysis, decision making, measurement development we concentrate here on its potential for helping researchers formulate their projects. The main objective of the study is to analyze the to ascertain the Sydenham chorea research output in world during 2000 to 2018. The specific objectives of the study are, Publication output, Share and Rank of Top 25 Most Productive countries in Sydenham chorea research during 2000–2018. etc.

Levodopa-Responsive Chorea: A Review.

Background:Chorea is one of the disabling movement disorders, and the number of drugs which can treat this disorder effectively is limited. Tetrabenazine and deutetrabenazine are the two drugs approved by the US-FDA for the treatment of chorea associated with HD. Levodopa can improve chorea in some disorders, and this review aims to provide information on the use of levodopa in chorea.Methods:A literature search was performed in February 2019 using the following terms “levodopa chorea,” “levodopa TITF-1,” levodopa brain-lung-thyroid syndrome,” and “levodopa Huntington's Disease.” The information regarding the etiology, outcome, and dose of levodopa was collected.Results:We found a total of 18 cases in the literature where the benefit was reported with levodopa. Majority of the cases were brain-thyroid-lung (BTL) syndrome (50%). Another 5 cases were HD (Huntington's Disease), one with PCH type 2 (Pontocerebellar hypoplasia type 2), one with meningovascular syphilis, and two patients with Sydenham chorea. The patients with BTL syndrome responded to a very low dose of levodopa.Discussion:This review suggests that levodopa has the potential to improve chorea in BTL syndrome while its use in chorea due to other disorders requires further study. BTL syndrome due to NKX2-1 mutation responded to levodopa while we did not find any case of chorea due to ADCY-5 mutation responding to levodopa.

Serum periostin levels in acute rheumatic fever: is it useful as a new biomarker?

ABSTRACTBackground: Acute rheumatic fever (ARF) continues to be a public health problem in low- and middle-income countries. Because there is no specific laboratory test for the exact diagnosis of ARF, the diagnosis is made by the modified Jones criteria. Periostin is an extracellular matrix protein which has been shown to be expressed during remodelling, mechanical stress and tissue repair. There are no data on the relationship between periostin and ARF.Aim: To evaluate serum periostin levels in patients with ARF and investigate its usefulness as a biomarker for diagnosing and monitoring the efficacy of treatment.Methods: Serum periostin levels were estimated in 31 patients with ARF and compared with a control group of 25 healthy patients. The control group comprised patients referred to the outpatient clinic for further evaluation of cardiac murmur, palpitations or chest pain. Patients who were diagnosed with any other cardiac or systemic illness after detailed systemic and cardiac examination were excluded.Results: The mean (SD) age at diagnosis was 12.1 (3.3) years in the patient group, 48.4% of whom were male. There were no significant differences in age or gender between patients and controls. All the study patients had various degrees of carditis, 58.1% had arthritis and 9.6% had Sydenham chorea. Mean (SD) serum periostin levels in patients with ARF on admission [58.4 (13.9) ng/mL] were significantly higher than in the control group [35.1 (10.7) ng/mL, p < 0.01] and were also significantly decreased in the patient group after treatment [35.1 (13.1) ng/mL, p < 0.01]. There was no significant difference in serum periostin levels regarding the severity of carditis in the patient group while patients with any severity of carditis had significantly higher periostin levels than the controls (p < 0.01). Periostin levels were significantly correlated with ESR and CRP values before treatment, but this correlation was detected for only ESR after treatment. For the initial diagnosis of ARF, a serum periostin level of 53.45 ng/mL was found to be the cut-off point with 80.6% sensitivity and 100% specificity.Conclusion: There was a significant increase in serum periostin levels in patients with ARF and a reduction after adequate treatment which was independent of the severity of carditis. Periostin may be a biomarker which acts as an acute phase reactant in ARF.

Autoimmune movement disorders

Autoimmune movement disorders (AMD) are increasingly recognized and include a wide spectrum of hyperkinetic, hypokinetic, sleep related and ataxic presentations. These range from chorea, tics, dystonic jerks, myoclonus, and neuromyotonia to hypo and akinetic rigid syndromes. The latter varieties encompass parkinsonism, stiff person syndrome (SPS) and progressive encephalomyelitis with rigidity and myoclonus (PERM). Ataxic syndromes include episodic ataxia associated with CASPR2 and post Herpes zoster cerebellitis and other rare paraneoplastic syndromes. The AMD have a broad spectrum of clinical phenotypes which are increasingly being recognized. They may present as an isolated movement disorder or as part of a wider clinical syndrome usually with encephalitic illnesses. They may follow infections, parainfectious, as in Paediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infection (PANDAS) and Sydenham chorea, or associate with an underlying occult malignancy (Leucine rich Glioma1 inactivated, Voltage Gated Potassium Channel Antibodies) associated Limbic encephalitis with brachio facial dystonic jerks and seizures linked with ovarian and testicular teratomas. In many instances no underlying cause is found, and ongoing research is revealing new markers and aetiologies for what was labelled idiopathic in the past. The autoimmune basis of these disorders is shown by the presence of antibodies or specific groups of CD8 cytotoxic cells mostly detected in the serum, cerebrospinal fluid and other tissues. Furthermore, their response to immunotherapies supports this notion and are the mainstay of current treatments. The latter include corticosteroids, therapeutic plasma exchange (TPE, PLEX), target specific biologicals (specific monoclonal antibodies mostly against B cells markers such as Ritixumab, anti CD20). Symptomatic therapies for the movement themselves and the associated presentation such as seizures, sleep and mood disturbances. The target antigens are diverse as mentioned above. They usually present subacutely and may deteriorate rapidly or follow a relapsing remitting course. Early positive recognition of these disorders is crucial as they are potentially treatable and in some case curable. This will avoid or reduce morbidity and improve long term outcomes.

Focus on Cardiologic Findings in 30 Children With PANS/PANDAS: An Italian Single-Center Observational Study

Objective: Cardiac involvement in PANS has not been clarified relying on the scientific literature available until today. It is known that streptococcal infections play a role in the etiology of a great number of diseases including Sydenham chorea and rheumatic fever, among others. Based on the suspected pathogenesis of PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections) reported in the medical literature, we decided to investigate the cardiologic involvement in children with a recent PANS/PANDAS diagnosis.Methods: The study population satisfies PANS (1) and PANDAS (2) criteria of diagnoses. Cardiologic assessment was performed through clinical examination, electrocardiography, and echocardiography.Results: In the selected pediatric population, a significant number of children presented mitral valve involvement, systolic murmurs and electrocardiographic abnormalities. High ASLOT levels did not seem to be associated to a cardiac involvement.Conclusions: Often PANS is difficult to diagnose because it is little known by physicians and most of the cardiologic findings described in this study are common among the healthy pediatric population. Also, ASLOT levels seems not to be predictive of cardiac involvement. Furthermore, the existence of PANDAS as a clinical entity is associated with a group of anti-neuronal autoantibodies found in Sydenham chorea is still controversial. We recommend a complete cardiologic evaluation in those children who meet the PANS/PANDAS diagnostic criteria.

Sydenham's Chorea; Clinical and Magnetic Resonance Imaging Findings, a Retrospective Observational Study in Children

AbstractThe purpose of this study was to evaluate the correlation between magnetic resonance imaging (MRI) findings and demographic and clinical characteristics, response to treatment times, and recurrence rates of Sydenham's chorea (SC), the most common of the acquired pediatric choreas. The clinical and radiological findings of 12 patients presenting to the pediatric neurology clinic in the previous 4 years and diagnosed with SC on the basis of the modified Jones criteria were investigated retrospectively from the hospital files. In addition, we measured the maximum prefrontal cortex and basal ganglia (globus pallidus, putamen, and caudate nucleus) thicknesses in the axial plane from patients' cerebral MRIs and compared these values with prefrontal cortex and basal ganglia thicknesses of a healthy control group measured using the same technique. Patient and control groups' cranial and basal ganglia MRIs were found to be normal. However, patients' globus pallidus thicknesses were significantly lower than those of the healthy control group. Additionally, the globus pallidus values of patients with recurrent SC and a prolonged healing time were lower than average. However, we determined no significant difference in terms of prefrontal motor cortex, caudate nucleus, or putamen thicknesses between the patient and control groups. Low globus pallidus thicknesses in patients with SC may indicate atrophy associated with globus pallidus involvement. Further experimental and prospective and long-term studies are needed for a better understanding of the factors affecting the pathophysiology, recurrence, and healing time of SC.

Molecular Mimicry, Autoimmunity, and Infection: The Cross-Reactive Antigens of Group A Streptococci and their Sequelae.

The group A streptococci are associated with a group of diseases affecting the heart, brain, and joints that are collectively referred to as acute rheumatic fever. The streptococcal immune-mediated sequelae, including acute rheumatic fever, are due to antibody and cellular immune responses that target antigens in the heart and brain as well as the group A streptococcal cross-reactive antigens as reviewed in this article. The pathogenesis of acute rheumatic fever, rheumatic heart disease, Sydenham chorea, and other autoimmune sequelae is related to autoantibodies that are characteristic of autoimmune diseases and result from the immune responses against group A streptococcal infection by the host. The sharing of host and streptococcal epitopes leads to molecular mimicry between the streptococcal and host antigens that are recognized by the autoantibodies during the host response. This article elaborates on the discoveries that led to a better understanding of the pathogenesis of disease and provides an overview of the history and the most current thought about the immune responses against the host and streptococcal cross-reactive antigens in group A streptococcal sequelae.

PANDAS and PANS: Clinical, Neuropsychological, and Biological Characterization of a Monocentric Series of Patients and Proposal for a Diagnostic Protocol

Objectives: Whether PANS (pediatric acute-onset neuropsychiatric syndrome) and PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection) represent true clinical entities is debated and data for a characteristic phenotype are still controversial. In this study, we aim to characterize clinical, neuropsychological, and biochemical aspects in a sample of PANS and PANDAS patients. Methods: Patients fulfilling a clinical diagnosis of PANS or PANDAS from 2014 to 2017 were enrolled. Neurological and psychiatric examination and biochemical and instrumental assessment results were collected. A neuropsychological battery was administered. For comparison purposes, a control group of patients with Sydenham's chorea (SC) was evaluated. Descriptive and comparative statistical analyses were performed. Results: Seven subjects received a diagnosis of PANS, 12 of PANDAS, and 11 of SC. Clinical presentation of PANS children showed statistically significant differences compared with both PANDAS and SC, in particular, with the presence of obsessive symptoms, behavioral regression, and somatic symptoms in the first group. Moreover, all PANS patients showed some neuropsychological deficits in visual-motor abilities, short- and long-term memory, and processing speed. Conclusions: Our experience confirms that patients with PANS had a complex clinical presentation and a compromised neuropsychological profile with respect to patients with PANDAS or SC. However, the absence of biological markers or instrumental alterations made the diagnosis of the two entities, PANS and PANDAS, a matter of exclusion. For these reasons, we propose a pilot diagnostic protocol that (when applied in a prospective manner) will allow comparison with similar childhood-onset neuropsychiatric disorders, such as obsessive-compulsive or tic disorders, and efficacy evaluation of different therapeutic approaches.

The differential diagnosis and treatment of sydenham's chorea: A case report

The differential diagnosis and treatment of sydenham's chorea: A case report

ERRONEOUS DIAGNOSIS OF PENICILLIN ALLERGY BASED ON MOLD HYPERSENSITIVITY TESTING COMPLICATING TREATMENT OF RHEUMATIC FEVER

Introduction The penicillin allergy label puts a patient at risk for higher mortality and increased rates of severe infections. We present a case of treatment for rheumatic fever with Sydenham chorea complicated by erroneously labeled penicillin allergy due to mold hypersensitivity. Case Description A 12-year old female became unable to stand from full-body choreiform movements and was found to have rheumatic fever. Her echocardiogram showed: “rheumatic carditis, thickened mitral valve leaflets.” Two months prior, she had group A streptococcus pharyngitis treated with cephalexin due to a label of penicillin allergy. Skin testing performed by her local ENT physician had been positive to penicillium mold and she was counseled to avoid all penicillin antibiotics. Penicillin antibiotic was not tested, and she had never had penicillin. She passed a penicillin oral challenge and was transitioned to monthly intramuscular penicillin G benzathine. Discussion An erroneous penicillin allergy label prevented prompt treatment of this patient's condition with gold standard therapy. Despite optimal adherence, oral prophylaxis options show increased rheumatic fever recurrence compared to parenteral therapy. Alternative medications such as sulfadiazine can have severe side effects including hepatitis and agranulocytosis. This case emphasizes the need to educate patients and providers that hypersensitivity to penicillium mold does not equate hypersensitivity with the penicillin antibiotic it secretes. Furthermore, authentication of a penicillin allergy label continues to be of utmost importance in allowing patients to receive optimal therapy.

Changes in recruitment of motor cortex excitation and inhibition in patients with drug-induced tardive syndromes

It has recently been suggested that drug-induced tardive syndromes (TS) might be due to maladaptive plasticity, which increases motor excitability in cerebral cortex and basal ganglia. In order to test this hypothesis, we performed the first measurements of cortical excitability in TS. Motor cortex excitability was examined using transcranial magnetic stimulation (TMS) in 22 TS patients and compared with that in 20 age and sex-matched healthy individuals. Resting and active motor threshold (RMT, AMT) and input-output curves (I/O curves) assessed corticospinal excitability. The duration of the contralateral silent period (cSP) at a range of stimulation intensities and ipsilateral silent period (iSP) were used as measures of inhibition. There were no significant differences in RMT and AMT between patients and controls, although the input-output curves were significantly steeper in patients. The cSP (at different stimulus intensities) and iSP were both longer in the patients compared to the control group. However, most of this difference could be accounted for by increased recruitment of motor evoked potentials (MEPs) in patients. TS is characterized by hyperexcitability of corticospinal output that might contribute to the lack of selectivity in muscle recruitment and contribute to excess involuntary movement. The findings are opposite to those in naturally-occurring hyperkinesia such as Sydenham's and Huntington's chorea, suggesting a fundamental difference in the pathophysiology.

Rheumatic Heart Disease: Pathogenesis and Vaccine

Rheumatic fever (RF) and rheumatic heart disease (RHD) follow untreated S. pyogenes throat infections in children who present susceptible genes that favor the development of autoimmune reactions. In this review, we focus on the genes that confer susceptibility and on the autoimmune reactions that occur due to molecular mimicry between human-tissue proteins and streptococcal M protein. Polyarthritis is the initial manifestation, which can evolve to carditis and severe valve damage; these culminate in rheumatic heart disease (RHD) or Sydenham's chorea, which affects the central nervous system. A perspective on vaccine development to prevent the disease is also discussed.