To evaluate the efficacy and safety of NH600001, a novel etomidate derivative, in gastrointestinal endoscopy, as well as its impact on adrenocortical function, two multicenter, double-blind, randomized, controlled clinical trials(NH600001-21 [Phase II trial] and NH600001-31 [Phase III trial]) were conducted in China. In NH600001-21, 160 gastroscopy subjects were randomized 1:1:1:1 to receive NH600001 (0.20, 0.25, or 0.30 mg/kg) and etomidate (0.30 mg/kg). In NH600001-31, 344 gastroscopy or colonoscopy subjects were randomized in a 1:1 ratio to receive NH600001 (0.25 mg/kg) and etomidate (0.30 mg/kg). The primary efficacy outcome was the rate of endoscopic success. Additionally, Safety and effects on adrenocortical function were also assessed. In NH600001-21, the 0.25 mg/kg NH600001 showed non-inferiority to etomidate based on the prespecified non-inferiority margin of -8% (Rate Difference [95% confidence interval], 5.0[-4.49 to 14.49]), whereas the 0.20 mg/kg and 0.30 mg/kg NH600001 did not meet statistical non-inferiority criteria (0[-11.54 to 11.54]; 0[-11.54 to 11.54]). The area under curve (AUC) of plasma cortisol change values within 0-4 h (∆Cortisol AUC0-4h) were significantly higher in the NH600001 treatment groups than in the etomidate group (P < 0.01). In NH600001-31, NH600001 (0.25 mg/kg) showed non-inferiority to etomidate (1.16[-0.44 to 2.76]). ∆Cortisol AUC0-4h in the NH600001 group, versus the etomidate group, were significantly higher (P < 0.001). Furthermore, NH600001 had a safety profile comparable to etomidate and elicited fewer myoclonus adverse events. In Conclusions, NH600001 has a sedative/anesthetic effect comparable to etomidate while reducing the risk of adrenocortical depression with a favorable safety profile. Chictr.org.cn identifier: ChiCTR2300069841, ChiCTR2400084095. Clinical Trial Number and Registry URL: NH60001-21, Identifier, ChiCTR2300069841 (Changsha, China;, principal investigator: Wen Ouyang, first registration date: March 28, 2023), https://www.chictr.org.cn; NH60001-31, Identifier, ChiCTR2400084095 (Changsha, China, principal investigator: Wen Ouyang, first registration date: May 10, 2024), https://www.chictr.org.cn.

In patients suffering catastrophic injury to the nervous system, a burst suppression pattern found on EEG is a rare finding. Usually, this pattern consists of bursts of mixed-frequency, variable-morphology waves alternating with suppressed periods and attenuation to an undetectable signal. This pattern can be difficult to assess, as burst suppression may be associated either with limited brain activity or with both clinical and electrographic seizures (ictal burst suppression). While this can occur at all ages, in adults it is most often seen with significant anoxic insult. We report a case of anoxic ictal burst suppression in a patient after cardiac arrest that was initially thought to represent anoxic myoclonus. Correlative clinical facial twitching and arm tonicity and flexion, which were abrogated by benzodiazepine and anesthetic administration, confirmed the ictal activity. Ictal burst suppression can be challenging both to recognize and to treat. We briefly review this phenomenon and the hypotheses regarding its potential mechanisms.

Opsoclonus myoclonus syndrome (OMS) is a rare inflammatory disease of the central nervous system characterized by ocular movements, ataxia, irritability, myoclonus, and sleep disturbances and is thought to result from variable etiologies. We report a case of OMS following severe malaria in a patient living with Human Immunodeficiency Virus (HIV). This is a 47-year-old woman, known to be HIV-positive, for the past 6 years, and on highly active antiretroviral therapy (HAART) with Tenofovir-Lamivudine-Atazanavir, to which she is strictly compliant. Her last viral load was undetectable. Two weeks after being treated for severe malaria due to Plasmodium falciparum, the patient presented with multidirectional ocular saccades associated with trunk myoclonus. This was subsequently followed by aggressive behavior sleep disturbances, and severe ataxia. The diagnosis of post-infectious opsoclonus-myoclonus was made after ruling out an HIV-related central nervous system (CNS) infection and a paraneoplastic origin. Initial management consisted of high doses of intravenous (IV) methylprednisolone which resulted in partial improvement of the symptoms. The subsequent addition of rituximab led to complete resolution of the symptoms and the restoration of functional autonomy. This case suggests a possible relationship between malaria and OMS in the context of HIV infection and highlights the potential benefit of an IV corticosteroid and rituximab combination therapy as a substitute for IV immunoglobulins in resource-limited settings.

Background and objectives: Movement disorders are an underrecognized phenomenon in Myelin Oligodendrocyte Glycoprotein-Associated Disease (MOGAD). The aim of this paper was to summarize all movement disorders previously described in MOGAD. Materials and Methods: We conducted a systematic literature search in PubMed, Web of Science, and Scopus in English, focusing on patients with MOGAD exhibiting a movement disorder, i.e., ataxia, tremor, dystonia, parkinsonism, chorea, athetosis, myoclonus, ballism, tics, stereotypies, dyskinesia. Results: We included 58 studies, with a total of 91 patients with MOGAD and a movement disorder (45.6% male, 54.4% female). Movement disorders had a mean latency of 2.1 years (±6.9, 0-42) after MOGAD onset; however, they could be the presenting feature (in approximately 70% of cases), especially in pediatric patients. Cerebellar ataxia was the most common movement disorder, occurring in 77 patients (84.6%). Tremor, postural and/or kinetic, was the second most common movement disorder (15%). Dystonia was reported in 8.8%, presenting as cervical, or limb dystonia or stereotyped dystonic episodes. Myoclonus and hypokinetic movement disorders were rare. Subcortical (in 60%), brainstem and cerebellar lesions (in 50% respectively) were the most common imaging findings. The most common accompanying symptoms were encephalopathy, fever and headache. Approximately half of the patients made a full recovery, and the other half showed a significant improvement in the movement disorder after immunomodulatory treatment, most commonly steroids. Conclusions: The new onset of a movement disorder, especially ataxia, in a young patient should prompt the search for MOGAD or can indicate a relapse in patients with an established diagnosis.

We describe three patients with subacute sclerosing panencephalitis (SSPE) presenting with hemiballistic slow myoclonus, an unusual and rarely reported motor phenotype. Periodic slow myoclonus is a hallmark clinical feature of SSPE and is considered pathognomonic, yet its expression is typically axial or generalized. Hemiballistic presentation of slow myoclonus is distinctly uncommon and has received little attention in the literature. These cases expand the recognized motor repertoire of SSPE and highlight a variant expression of periodic cortical discharges involving asymmetric ballistic recruitment of proximal limb musculature.

Neurodegenerative diseases are often presented with myoclonus, sudden, short-term, involuntary muscle contractions («flinching»). According to the literature, myoclonus in Alzheimer's disease (AD) can occur up to 40-50% in cases of disease with early onset and in atypical forms. Importantly, epileptic myoclonus may indicate a risk of seizures with loss of consciousness, convulsions, and epileptiform activity, which may lead to more rapid progression of cognitive deficits. Diagnosis of myoclonus is essential for timely treatment and improving the quality of life of AD patients. The paper describes the main features of myoclonus in AD, the possibility of using additional examination methods, in particular video-electroencephalographic (video-EEG) monitoring for differential diagnosis and etiology clarification, and also presents a clinical case of a patient with AD and epileptic and non-epileptic myoclonus.

Hypertrophic olivary degeneration (HOD) is a rare form of transsynaptic degeneration resulting from disruption of the Guillain-Mollaret triangle, typically presenting with palatal tremor, ataxia, and nystagmus. Mutations in the Ring Finger Protein 170 (RNF170) gene have been associated with autosomal dominant sensory ataxia. However, the coexistence of HOD and an RNF170 mutation has rarely been reported. A 60-year-old female presented with progressive gait instability, vertigo, oscillopsia, and a sensation of walking on cotton. Neurological examination revealed pendular nystagmus, slow rhythmic palatal myoclonus, broad-based gait, positive Romberg sign, and clumsy tandem gait. Cognitive function was intact. Magnetic resonance imaging showed bilateral hypertrophy of the inferior olivary nuclei with T2 hyperintensity, consistent with HOD, along with mild right cerebellar atrophy. No brainstem infarction, hemorrhage, or demyelinating lesions were identified. Genetic testing revealed a heterozygous mutation in the RNF170 gene. There was no family history of ataxia, and screening for common spinocerebellar ataxia genes was negative. This case describes an unusual presentation of HOD without an identifiable secondary structural lesion, occurring in a patient with an RNF170 mutation. The findings suggest that RNF170-related neurodegeneration may predispose to or mimic HOD. In patients with unexplained HOD and prominent ataxia, screening for RNF170 gene mutations should be considered.

A 63-year-old female patient presented with tremor, articulation difficulties, muscular weakness, and reduced alertness. Over the course of hospitalization, her neurological condition progressively worsened, with the development of myoclonus and ultimately a comatose state. Cerebral imaging, EEG, and cerebrospinal fluid analysis revealed no diagnostic abnormalities. Retrospective review showed an elevated lithium level seven weeks prior to presentation in the emergency department. Following hemodialysis, her neurological status gradually improved. This case highlights the clinical relevance of chronic lithium toxicity as a potentially reversible cause of severe encephalopathy.

Orthostatic tremor (OT) is a rare movement disorder defined by high-frequency tremor predominantly in the standing position, often causing mobility limitation and reduced quality of life. Its natural history, disease burden and treatment response remain poorly understood due to limited longitudinal evidence. The Longitudinal Orthostatic Tremor Study (LOTS) aims to characterise clinical, demographic and therapeutic trajectories in OT and orthostatic myoclonus over 5 years.