Background KCNMA1‐linked channelopathy is a rare movement disorder first reported in 2005. Paroxysmal non‐kinesigenic dyskinesia (PNKD) in KCNMA1‐linked channelopathy is the most common symptom in patients harboring the KCNMA1‐N999S mutation. PNKD episodes occur up to hundreds of times daily with significant morbidity and limited treatment options, often in the context of epilepsy. Cases We report 6 cases with the KCNMA1‐N999S variant treated with lisdexamfetamine (0.7–1.25 mg/kg/day), a pro‐drug of dextroamphetamine. Data were collected retrospectively from interviews and chart review. Parent‐reported daily PNKD episode counts were reduced under treatment, ranging from a 10‐fold decrease to complete resolution. Conclusion Our findings suggest that lisdexamfetamine is an effective therapy for PNKD3 (KCNMA1‐associated PNKD). Treatment produced dramatic reductions in debilitating dyskinesia episodes, without provocation or exacerbation of other KCNMA1‐associated symptoms such as seizures.

A stroke should be considered in cases of neurologic decompensation associated with inherited metabolic disorders. A resultant stroke could be a classical ischemic stroke (vascular stroke) or more commonly a “metabolic stroke.” A metabolic stroke begins with metabolic dysfunctions, usually caused by a stressor, and leads to the rapid onset of prolonged central neurological deficits in the absence of vessel occlusion or rupture. The cardinal features of a metabolic stroke are stroke-like episodes without the confirmation of ischemia in the typical vascular territories, such as that seen in classic thrombotic or embolic strokes. Identifying the underlying cause of a metabolic stroke is essential for prompt and appropriate treatment. This study reviews the major inherited metabolic disorders that predispose patients to pediatric stroke, with an emphasis on the underlying mechanisms, types, and management.

Cerebral palsy is a syndrome that encompasses a large group of childhood movement and posture disorders that result from a lesion occurring in the developing brain. The clinical presentation of many metabolic and genetic conditions, particularly in highly consanguineous populations, can mimic cerebral palsy particularly at early age. The aim of this review article is to identify the clinical features that should alert the physician to the possibility of disorders that resemble cerebral palsy, the clinical and neuroimaging red flags, and highlight some metabolic and genetic conditions which may present with spasticity, ataxia and dyskinesia. In the case of metabolic or genetic disorder, making a precise diagnosis is particularly important for the possibility of treatment, accurate prognosis and genetic counseling.

Previous reviews have described the features of brain involvement in pediatric-onset metabolic disorders with Mendelian and mitochondrial inheritance, but only a few have focused on spinal cord abnormalities. An increasing number of metabolic disorders with Mendelian and mitochondrial inheritance in children with predominant spinal cord involvement has been recognized. Spinal cord involvement may be isolated or may occur more frequently with brain involvement. Timely diagnosis and occasional genetic counseling are needed for timely therapy. Therefore, clinicians must be aware of the clinical, laboratory, and radiographic features of these disorders. In this review, we describe pediatric-onset metabolic disorders with Mendelian and mitochondrial inheritance and predominant spinal cord involvement. Furthermore, we provide an overview of these conditions, including background information and examples that require rapid identification, focusing on treatable conditions; that would be catastrophic if they are not recognized.

Purpose Primary and secondary conditions that cause thiamine deficiency can result in similar symptoms in children, including acute episodes of encephalopathy and bilateral symmetrical brain lesions. In this study, we investigated the role of mammillary body (MB) involvement in SLC19A3-BTBGD patients and the differentiation between BTBGD and Wernicke's encephalopathy based on Magnetic Resonance Imaging (MRI) findings.Methods We conducted a retrospective study of 90 patients with genetically confirmed BTBGD. Two certified neuroradiologists independently reviewed the brain MRI scans, focusing on the involvement or sparing of specific regions such as the mesencephalon, cerebellum, caudate nuclei, globus pallidi, putamina, thalami, cortical and subcortical regions, MBs, and deep white matter.Results Clinically, all patients developed acute/subacute encephalopathy triggered by nonspecific febrile illnesses or mild trauma. MRI scans showed bilateral caudate lesions, putamen lesions, cortical-subcortical areas of the cerebral hemispheres, ventromedial region of the thalamus, cerebellar lesions, brainstem lesions, periaqueductal region, spinal cord lesions, and lesions in the globus pallidus. However, none of the patients had any mammillary lesions.Conclusion We found no MB involvement in 90 patients with BTBGD caused by the same homozygous variant of SLC19A3. Differentiating between BTBGD and Wernicke's encephalopathy based on MRI findings is critical for clinical decisions about treatment, prognosis, and genetic counselling. This study provides a crucial point in ruling out Wernicke's encephalopathy, especially in adults, and favouring BTBGD before the results of genetic testing are available. MRI is of utmost importance in the diagnosis and differentiation of these conditions.

No abstract