GLUT1 deficiency is a rare neurometabolic disorder that can be effectively treated with ketogenic diet. However, this condition is underdiagnosed due to its nonspecific, overlapping, and evolving symptoms with age. We retrospectively reviewed the clinical course of nine patients diagnosed with GLUT1 deficiency, based on SLC2A1 mutations and/or glucose concentration in cerebrospinal fluid. The patients included eight boys and one girl who initially presented with seizures (44%, 4/9) or delayed development (44%, 4/9) before 2 years of age, except for one patient who presented with apnea as a neonate. Over the clinical course, all of the children developed seizures of the mixed type, including absence seizures and generalized tonic–clonic seizures. About half (56%, 5/9) showed movement disorders such as ataxia, dystonia, or dyskinesia. We observed an evolution of phenotype over time, although this was not uniform across all patients. Only one child had microcephaly. In five patients, ketogenic diet was effective in reducing seizures and movement symptoms, and the patients exhibited subjective improvement in cognitive function. Diagnosing GLUT1 deficiency can be challenging due to the phenotypic variability and evolution. A high index of clinical suspicion in pediatric and even older patients with epilepsy or movement disorders is key to the early diagnosis and treatment, which can improve the patient's quality of life.
Apnea ; Ataxia ; Cerebrospinal Fluid ; Child ; Clothing ; Cognition ; Dyskinesias ; Dystonia ; Early Diagnosis ; Epilepsy ; Epilepsy, Absence ; Female ; Glucose ; Humans ; Infant, Newborn ; Ketogenic Diet ; Microcephaly ; Movement Disorders ; Phenotype ; Quality of Life ; Retrospective Studies ; Seizures

A 43-year-old woman suffered from drooling and dysphagia after a stroke in the left posterior inferior cerebellar artery territory. Videofluoroscopic swallowing study showed compatible findings of cricopharyngeal dysphagia. Despite the injection of botulinum neurotoxin, no symptom improvement was achieved and pharyngeal dystonia was considered as the cause. Medications for dystonia dramatically helped with saliva control and resulted in a small improvement in the progression of food from the pharyngeal to esophageal phase. After adjusting the drug dose, the patient was able to perform social activities without drooling. Moreover, she could consume food orally; however, this was limited to small amounts of liquid, and the main method of nutrition support was via an orogastric tube. Therefore, we suggest that physicians should make a differential diagnosis of combined dystonia in patients complaining of dysphagia by esophageal manometry and electromyography.
Adult ; Arteries ; Deglutition ; Deglutition Disorders ; Diagnosis, Differential ; Drug Therapy ; Dystonia ; Electromyography ; Female ; Humans ; Manometry ; Methods ; Saliva ; Sialorrhea ; Stroke

Dopa-responsive dystonia (DRD) is characterized by lower limb-onset, diurnally fluctuating dystonia and dramatic and sustained response to levodopa treatment. Segawa disease, an autosomal dominant deficiency of guanosine triphosphate cyclohydrolase 1 (encoded by GCH1) is the most common and well-known condition manifesting as DRD. However, similar clinical manifestations can be seen in individuals with deficiencies of other enzymes that are involved in the biosynthesis of dopamine. We describe the case of an 11-year-old girl who presented with abnormal gait, which had initially begun 2 years back. The patient showed diurnally fluctuating dystonia in both legs. She was able to walk without support in the morning, but was unable to stand without support in the evening. She had been diagnosed as having spastic cerebral palsy and had been managed with physical therapy at a local rehabilitation clinic. The patient had been healthy until the development of dystonia, and did not have a history of perinatal problems or developmental delay. Routine hematologic and biochemical test results were normal. Brain magnetic resonance imaging and electroencephalography showed no abnormalities. When levodopa was administered, the patient's abnormal gait dramatically improved 1 hour after receiving the medication. Genetic testing for the GCH1 gene revealed a missense mutation (c.293C>T [p.A98V]) that has previously been reported in patients with DRD. This case demonstrated that a levodopa trial is vital for accurate and early diagnosis of DRD in patients with dystonia resulting from an unknown cause.
Brain ; Cerebral Palsy* ; Child ; Diagnostic Errors ; Dopamine ; Dystonia* ; Early Diagnosis ; Electroencephalography ; Female ; Gait ; Genetic Testing ; Guanosine Triphosphate ; Humans ; Leg ; Levodopa ; Magnetic Resonance Imaging ; Mutation, Missense ; Rehabilitation

Previously, we defined DRD as a syndrome of selective nigrostriatal dopamine deficiency caused by genetic defects in the dopamine synthetic pathway without nigral cell loss. DRD-plus also has the same etiologic background with DRD, but DRD-plus patients have more severe features that are not seen in DRD because of the severity of the genetic defect. However, there have been many reports of dystonia responsive to dopaminergic drugs that do not fit into DRD or DRD-plus (genetic defects in the dopamine synthetic pathway without nigral cell loss). We reframed the concept of DRD/DRD-plus and proposed the concept of DRD look-alike to include the additional cases described above. Examples of dystonia that is responsive to dopaminergic drugs include the following: transportopathies (dopamine transporter deficiency; vesicular monoamine transporter 2 deficiency); SOX6 mutation resulting in a developmentally decreased number of nigral cells; degenerative disorders with progressive loss of nigral cells (juvenile Parkinson's disease; pallidopyramidal syndrome; spinocerebellar ataxia type 3), and disorders that are not known to affect the nigrostriatal dopaminergic system (DYT1; GLUT1 deficiency; myoclonus-dystonia; ataxia telangiectasia). This classification will help with an etiologic diagnosis as well as planning the work up and guiding the therapy.
Ataxia ; Classification ; Diagnosis ; Dopamine ; Dopamine Agents ; Dystonia* ; Humans ; Parkinson Disease ; Spinocerebellar Ataxias ; Vesicular Monoamine Transport Proteins

OBJECTIVE: The inability to propel a bolus of food successfully from the posterior part of the oral cavity to the oropharynx is defined as transfer dysphagia. The present case series describes the varied presentation of transfer dysphagia due to focal dystonia and highlights the importance of early detection by following up on strong suspicions. METHODS: We describe seven cases of transfer dysphagia due to focal dystonia. Transfer dysphagia as a form of focal dystonia may appear as the sole presenting complaint or may present with other forms of focal dystonia. RESULTS: Four out of seven patients had pure transfer dysphagia and had previously been treated for functional dysphagia. A high index of suspicion, barium swallow including videofluoroscopy, associated dystonia in other parts of the body and response to drug therapy with trihexyphenidyl/tetrabenazine helped to confirm the diagnosis. CONCLUSION: Awareness of these clinical presentations among neurologists and non-neurologists can facilitate an early diagnosis and prevent unnecessary investigations.
Barium ; Deglutition Disorders ; Diagnosis ; Drug Therapy ; Dystonia ; Dystonic Disorders ; Early Diagnosis ; Humans ; Mouth ; Oropharynx

BACKGROUND AND OBJECTIVES: Adductor type spasmodic dysphonia (ADSD) is neurogenic disorder and focal laryngeal dystonia, while muscle tension dysphonia (MTD) is caused by functional voice disorder. Both ADSD and MTD may be associated with excessive supraglottic contraction and compensation, resulting in a strained voice quality with spastic voice breaks. The aim of this study was to determine the utility of spectrogram analysis in the differentiation of ADSD from MTD. MATERIALS AND METHODS: From 2015 through 2017, 17 patients of ADSD and 20 of MTD, underwent acoustic recording and phonatory function studies, were enrolled. Jitter (frequency perturbation), Shimmer (amplitude perturbation) were obtained using MDVP (Multi-dimensional Voice Program) and GRBAS scale was used for perceptual evaluation. The two speech therapist evaluated a wide band (11,250 Hz) spectrogram by blind test using 4 scales (0–3 point) for four spectral findings, abrupt voice breaks, irregular wide spaced vertical striations, well defined formants and high frequency spectral noise. RESULTS: Jitter, Shimmer and GRBAS were not found different between two groups with no significant correlation (p>0.05). Abrupt voice breaks and irregular wide spaced vertical striations of ADSD were significantly higher than those of MTD with strong correlation (p < 0.01). High frequency spectral noise of MTD were higher than those of ADSD with strong correlation (p < 0.01). Well defined formants were not found different between two groups. CONCLUSION: The wide band spectrograms provided visual perceptual information can differentiate ADSD from MTD. Spectrogram analysis is a useful diagnostic tool for differentiating ADSD from MTD where perceptual analysis and clinical evaluation alone are insufficient.
Acoustics ; Compensation and Redress ; Diagnosis, Differential ; Dysphonia* ; Dystonia ; Humans ; Muscle Spasticity ; Muscle Tonus* ; Noise ; Voice ; Voice Disorders ; Voice Quality ; Weights and Measures

Voice disorder is classified into three categories, structural, neurogenic and functional dysphonia. Neurogenic dysphonia refers to a disruption in the nerves controlling the larynx. Common examples of this include complete or partial vocal cord paralysis, spasmodic dysphonia. Also it occurs as part of an underlying neurologic condition such as Parkinson's disease, myasthenia gravis, Lou Gehrig's disease or disorder of the central nervous system that causes involuntary movement of the vocal folds during voice production. Functional dysphonia is a voice disorder in the absence of structual or neurogenic laryngeal characteristics. A near consensus exist that Muscle tension dysphonia (MTD) is functional voice disorder wherein hyperfunctional laryngeal muscle activity whereas Spasmodic dysphonia (SD) is neurogenic, action-induced focal laryngeal dystonia including several subtype. Both Adductor type spasmodic dysphonia (AdSD) and MTD may be associated with excessive supraglottic contraction and compensation, resulting in a strained voice quality with spastic voice breaks. It makes these two disorders extremely difficult to differentiate based on clinical interpretation alone. Because treatment for AdSD and MTD are quite different, correct diagnosis is important. Clinician should be aware of the specific vocal characteristics of each disease to improve therapeutic outcome.
Amyotrophic Lateral Sclerosis ; Central Nervous System ; Compensation and Redress ; Consensus ; Diagnosis ; Diagnosis, Differential* ; Dyskinesias ; Dysphonia* ; Dystonia ; Laryngeal Muscles ; Larynx ; Muscle Spasticity ; Muscle Tonus ; Myasthenia Gravis ; Parkinson Disease ; Vocal Cord Paralysis ; Vocal Cords ; Voice ; Voice Disorders ; Voice Quality

The clinical manifestations of five children with paroxysmal kinesigenic dyskinesia (PKD) were retrospectively analyzed and their gene mutations were analyzed by high-throughput sequencing and chromosome microarray. The 5 patients consisted of 4 males and 1 female and the age of onset was 6-9 years. Dyskinesia was induced by sudden turn movement, scare, mental stress, or other factors. These patients were conscious and had abnormal posture of unilateral or bilateral extremities, athetosis, facial muscle twitching, and abnormal body posture. The frequency of onset ranged from 3-5 times a month to 2-7 times a day, with a duration of <30 seconds every time. Electroencephalography showed no abnormality in these patients. Three patients had a family history of similar disease. The high-throughput sequencing results showed that a heterozygous mutation in the PRRT2 gene, c.649_650insC (p.R217PfsX8), was found in two patients; the mutation c.436C>T (p.P146S) was found in one patient; a splice site mutation, IVS2-1G>A, was found in one patient. The two mutations c.436C>T and IVS2-1G>A had not been reported previously. The chromosome microarray analysis was performed in one patient with negative results of gene detection, and the chromosome 16p11.2 deletion (0.55 Mb) was observed. Low-dose carbamazepine was effective for treatment of the 5 patients. PKD is a rare neurological disease. The detection of the PRRT2 gene by multiple genetic analysis can help the early diagnosis of PKD.
Carbamazepine ; therapeutic use ; Child ; Chromosome Deletion ; Chromosomes, Human, Pair 16 ; Dystonia ; complications ; diagnosis ; drug therapy ; genetics ; Electroencephalography ; Female ; Humans ; Male ; Membrane Proteins ; genetics ; Mutation ; Nerve Tissue Proteins ; genetics

OBJECTIVETo explore the feasibility of using PCR-based capillary electrophoresis method to analysis mutation of the TOR1A gene in a family affected with primary torsion dystonia (PTD).

METHODSPeripheral blood sample was collected from proband and amnionic fluid from her fetus for the extraction of DNA. The 5th exon of the TOR1A gene and its flanking sequences were amplified with PCR and analyzed with agarose electrophoresis, fluorescence labeled fragment analysis and Sanger sequencing.

RESULTSFluorescence labeled fragment analysis was performed through capillary electrophoresis, which showed that the proband carried a c.907_909delGAG (p.Glu303del) deletional mutation of the TOR1A gene. The result was verified by Sanger sequencing. The fetus DNA was also found with the same mutation by capillary electrophoresis, inferring that the fetus was probably affected with the disease.

CONCLUSIONThe mutation of c.907_909delGAG of the TOR1A gene was speculated as pathologic cause of proband in this family. Fragment analysis by capillary electrophoresis combined with DNA sequencing is an efficient test for small deletional mutations and feasible for its prenatal diagnosis.

Adult ; Dystonia ; diagnosis ; genetics ; Electrophoresis, Capillary ; Female ; Humans ; Molecular Chaperones ; genetics ; Mutation ; Prenatal Diagnosis ; Sequence Analysis, DNA

PURPOSE: Paroxysmal kinesigenic dyskinesia (PKD) is a rare paroxysmal movement disorder characterized by recurrent and brief dyskinesia attacks triggered by sudden voluntary movement. The diagnosis of PKD is based on clinical findings, and mutations in the proline-rich transmembrane protein 2 (PRRT2) gene have been identified as the cause of PKD. Two Korean cohorts have been reported on PRRT2 mutation analysis in PKD patients. The purpose of this study was to determine the mutation spectrum of the PRRT2 gene and to examine the clinical characteristics associated with PRRT2 mutations. METHODS: We studied 23 members of four families with familial PKD and two families with sporadic PKD which included 9 patients and 2 patients, respectively. Mutation analysis of the PRRT2 gene was performed using Sanger sequencing. Clinical features of PKD were compared between patients with a PRRT2 mutation and those with no detectable PRRT2 mutation. RESULTS: PRRT2 mutations were detected in three of four PKD families (75%), and in none of the two sporadic cases (0%). All detected PRRT2 mutations were c.649dupC (p.Arg217Profs*8). Subjects with detected PRRT2 mutations had earlier age at onset and longer duration of attacks. CONCLUSION: As previously reported in Korean PKD patients, our results confirmed that PRRT2 is a major causative gene for familial PKD, and the c.649dupC is the most frequent mutation. PRRT2 mutation analysis is required for the molecular diagnosis of familial PKD and for evaluating the clinical manifestations of PKD.
Age of Onset ; Cohort Studies ; Diagnosis ; Dyskinesias* ; Dystonia ; Humans ; Movement Disorders