Background/Objectives: In individuals with a genetic predisposition, acute rheumatic fever (ARF) can manifest as arthritis, carditis, chorea, subcutaneous nodules, and erythema marginatum. It occurs after a latent period of 1-3 weeks of untreated upper respiratory tract infections caused by group A beta-hemolytic streptococci. The presence and severity of carditis determine the prognosis for ARF. Carditis manifests as pancarditis, and although all patients have pericarditis, not all experience a pericardial effusion. Patients with severe carditis exhibit pericardial effusion more frequently. The physiopathology of ARF remains unclear, specifically which patients will experience carditis, arthritis, or chorea. However, the Turkish population has fully clarified the physiopathology and clinical features of Familial Mediterranean fever (FMF), a common rheumatic disease. In the Turkish population, the heterozygous positivity rate for the FMF gene mutation is 15-35%. For these reasons, we examined the presence of FMF gene mutations in our patients to determine whether there is a correlation between the clinical course of ARF and the FMF gene mutation. Methods: The study included 60 patients with arthritis (n = 11), carditis (n = 26), or both (n = 23), as well as 60 healthy controls. These pediatric patients underwent screening for mutations in exons 2 and 10 of the MEFV gene. Results: There was no statistically significant difference between the patient and control groups in terms of the incidence of MEFV gene mutations in exon 10. However, in patients with ARF, the exon 2 E148Q variant was significantly more common than in the control group. Conclusions: This study suggests a relationship between certain clinical manifestations of ARF and MEFV gene mutations in children.

Although adult Huntington's disease (HD) studies have significantly advanced our understanding of the course of degeneration, they may underrepresent critical neurodevelopmental aspects of the disease. Significant gaps remain in understanding how mutant huntingtin affects early neurodevelopment, its long-term impact, as well as potential implications for treatment outcomes. The Childhood to Adult Neurodevelopment in Gene-Expanded Huntington's Disease (ChANGE-HD; NCT01951588) study aims to evaluate brain structure and function in premanifest, at-risk children and young adults, and explore HD's developmental origins. Here, we introduce the ChANGE-HD study, which will investigate and integrate the neurodevelopmental and neurodegenerative aspects of HD. The ChANGE-HD study is a prospective, seven-year multi-site observational study with an accelerated longitudinal design, where participants are not bound to a fixed schedule across multiple visits. Four hundred and fifty participants aged 6-30 years who are at risk for HD will be recruited and asked to return for multiple visits (if possible). At each visit, cognitive, motor, behavioral, blood/saliva, and MRI data are collected. Alongside ChANGE-HD, we are also recruiting individuals for the juvenile-onset HD (JOHD) study to investigate the neuropathology of this rarer form of HD. ChANGE-HD represents the first prospective multi-site study to systematically document brain structure and function during the premanifest phase of HD in children and young adults. Data collection is ongoing with first results anticipated in 2026-2027. The ChANGE-HD approach is likely to provide novel physiological insights and guide the development of therapeutic strategies tailored to both the developmental and degenerative phases of the disease.

This Perspective outlines the challenges addressed at the first Annual Parkinson's Disease (PD) Prevention Think Tank, held on November 20-21, 2025 in Gainesville, Florida at the Fixel Institute. Over the course of two days, attendees from a wide variety of disciplines, including movement disorders neurology, environmental sciences, agriculture, public policy, public health, patient advocate groups, and more, discussed the current state of primary prevention research in PD, examined the lessons learned from prevention research in other disorders, and identified necessary regulatory and policy actions for moving toward primary prevention of PD. Eight key components of primary prevention are identified (8 C's): accurately Count incidence and prevalence, Conduct longitudinal cohort studies, induce policy Change, Counsel on individual behavior change, Communicate clearly with the general public and with key stakeholders, form multi-centric Coalitions across neurodegenerative disorders, apply Cross-disciplinary approaches, and provide sustained financial Commitment to support ongoing prevention and mitigation efforts. These proceedings serve as an initial call-to-action for at-risk individuals, the clinicians who care for them, and for policymakers.

Huntington's disease (HD) is characterised by progressive motor impairment and neuropsychiatric dysfunction; however, early presentations may be dominated by psychiatric symptoms. We describe a man in his 50s with a documented diagnosis of HD established several years prior and a strong family history, whose early examinations showed minimal motor findings despite severe psychiatric manifestations including a prior suicide attempt and psychosis. Over subsequent years, serial examinations documented clear motor progression to abnormal gait, weakness and prominent choreiform movements, with intermittent wheelchair use. Bedside cognitive examination during incarceration revealed impaired set-shifting and markedly reduced phonemic and semantic verbal fluency, consistent with the HD cognitive phenotype. Neurology consultation was offered during hospitalisation but declined, and outpatient referral was interrupted by incarceration. During incarceration, severe choreiform movements and impaired insight were documented, with fluctuation in motor severity across settings. This case illustrates the evolution from neuropsychiatric-predominant HD to advanced motor involvement in the context of fragmented continuity of neurologic care, highlighting the importance of longitudinal specialist follow-up in progressive neurodegenerative disease.

Sydenham's chorea (SC) is the most common form of acquired chorea in childhood and a neurological manifestation of acute rheumatic fever (ARF). It is characterized by involuntary, rapid, and irregular movements. Although the diagnosis is clinical, neuroimaging can play a valuable complementary role. SC arises from an autoimmune response triggered by a streptococcal infection, targeting the basal ganglia. In some cases, it may be the sole manifestation of ARF. We present two pediatric cases with acute hemichorea. In one of them, chorea was the only clinical manifestation. Brain MRIs showed punctate ischemic lesions compatible with postinfectious vasculitis, allowing exclusion of other causes of vasculopathy and movement disorders. Both patients were treated with valproic acid and aspirin as an antiplatelet agent. Clinical and radiological improvement was observed in both cases, allowing treatment withdrawal after six months without symptom recurrence.

Huntington's disease (HD) is a progressive neurodegenerative disorder characterized by motor, cognitive, and psychiatric symptoms. Tetrabenazine (TBZ), a vesicular monoamine transporter 2 inhibitor, is commonly used to manage chorea; however, it may exhibit fluctuating plasma levels and elicit frequent adverse events. In this study, we aimed to clarify the effects of TBZ deuteration on its safety profile. We compared the safety profiles of TBZ and deutetrabenazine (DTBZ) in real-world clinical practice using disproportionality analysis and the large-scale pharmacovigilance database, VigiBase-the WHO's global database of adverse drug reactions. Adverse event signals were assessed using the information component (IC). Seriousness was classified according to clinical outcome, and time to onset (TTO) was analyzed for selected events. TBZ showed signals for disorientation, dystonia, and sleep disorders (IC025 > 0), whereas DTBZ did not. Serious adverse events were reported in 54.7% of TBZ cases and 37.9% of DTBZ cases. The TTO of sleep disorder was also evaluated; however, the number of cases with available TTO information was limited. DTBZ showed fewer adverse event signals and a lower proportion of serious adverse events than TBZ. These findings suggest potential differences in the safety profiles of the two drugs, which may influence tolerability in the treatment of HD.

Hyperglycemic chorea (HC), also known as diabetic striatopathy, is a rare, potentially reversible complication of poorly controlled diabetes mellitus. It manifests as involuntary, often unilateral, choreiform or ballistic movements. Despite its clinical significance, HC remains underrecognized, and its pathophysiology is not fully understood. We present a case of HC and a narrative review of the published case reports to characterize its epidemiology, clinical features, imaging findings, treatment, and outcomes. We conducted a narrative review of case reports and case series on HC using PubMed/MEDLINE from inception to 1 September 2024, following PRISMA guidelines. Inclusion criteria were English-language reports of adult patients (≥18 years) with chorea attributed to hyperglycemia. A total of 80 publications encompassing 100 patients were included. The mean age was 66.6 years, with a female predominance (67%). Hemichorea was more common (71%), with left-sided preponderance. Most patients (75%) had a prior diagnosis of diabetes, and the mean presenting blood glucose and HbA1c were 468 mg/dL and 13.7%, respectively. Imaging revealed basal ganglia hyperintensity on MRI in 80% of cases. Treatment primarily involved insulin therapy, with 69% receiving adjunctive anti-chorea medications. Symptom resolution occurred in 73.9% of patients, with a mean recovery time of 36.7 days. HC is an important differential diagnosis for acute-onset chorea in elderly patients with uncontrolled diabetes. Prompt recognition and glycemic control are key to symptom resolution. Neuroimaging, particularly MRI, plays a crucial role in diagnosis, and adjunctive pharmacotherapy may aid in symptom management.

Nonketotic hyperglycemic hemichorea, also known as diabetic striatopathy, is a rare but reversible neurological complication of poorly controlled diabetes mellitus that can mimic acute cerebrovascular events. We report a case of an elderly woman with poorly controlled type 2 diabetes mellitus (glycated hemoglobin (HbA1c) 12.6%) who presented with a 2-week history of progressive, involuntary movements involving the left upper and lower extremities. The movements were continuous, non-suppressible, and consistent with hemichorea. Laboratory evaluation revealed severe hyperglycemia (glucose >500 mg/dL), normal serum osmolality (295 mOsm/kg), and negative ketones, confirming a nonketotic state. Non-contrast computed tomography of the head demonstrated hyperdensity of the right caudate and putamen. Magnetic resonance imaging showed T1-weighted hyperintensity involving the right basal ganglia. The differential diagnosis included acute stroke and neurodegenerative etiologies; however, clinical and radiologic findings supported diabetic striatopathy. The patient was treated with intravenous fluids and insulin therapy, resulting in rapid glycemic control and significant improvement in symptoms without the need for neuroleptic agents. At the three-month follow-up, she demonstrated near-complete clinical resolution, with repeat imaging confirming near-complete resolution of prior abnormalities. This case highlights nonketotic hyperglycemic hemichorea as a reversible stroke mimic and underscores the importance of early recognition and glycemic control. It also emphasizes how behavioral factors, such as needle phobia, can contribute to poor disease control and lead to significant neurological complications.