Clinical and Genetic Spectrum of Myotonia Congenita in Turkish Children.

BACKGROUND: Myotonia congenita is the most common form of nondystrophic myotonia and is caused by Mendelian inherited mutations in the CLCN1 gene encoding the voltage-gated chloride channel of skeletal muscle. OBJECTIVE: The study aimed to describe the clinical and genetic spectrum of Myotonia congenita in a large pediatric cohort. METHODS: Demographic, genetic, and clinical data of the patients aged under 18 years at time of first clinical attendance from 11 centers in different geographical regions of Türkiye were retrospectively investigated. RESULTS: Fifty-four patients (mean age:15.2 years (±5.5), 76% males, with 85% Becker, 15% Thomsen form) from 40 families were included. Consanguineous marriage rate was 67%. 70.5% of patients had a family member with Myotonia congenita. The mean age of disease onset was 5.7 (±4.9) years. Overall 23 different mutations (2/23 were novel) were detected in 52 patients, and large exon deletions were identified in two siblings. Thomsen and Becker forms were observed concomitantly in one family. Carbamazepine (46.3%), mexiletine (27.8%), phenytoin (9.3%) were preferred for treatment. CONCLUSIONS: The clinical and genetic heterogeneity, as well as the limited response to current treatment options, constitutes an ongoing challenge. In our cohort, recessive Myotonia congenita was more frequent and novel mutations will contribute to the literature.

Effect of Levetiracetam Usage on Serum Creatine Phosphokinase Concentration in Patients with Epilepsy.

BACKGROUND: Levetiracetam (LEV) is a widely used antiepileptic drug (AED) in the treatment of various type of seizures, including generalized epileptic seizure as well as focal seizures, and it is generally well tolerated. Common side effects of LEV are somnolence, asthenia, dizziness, mood changes, kidney dysfunction, minor infections, and thrombocytopenia. Recently, increased creatine phosphokinase (CPK) concentration or rhabdomyolysis after LEV administration has been reported. The goal of the study was to evaluate clinical risk factors associated with increased CPK concentration or rhabdomyolysis in LEV administration. MATERIALS AND METHODS: One hundred and sixty children were enrolled. The risk factors were retrospectively analyzed. RESULTS: Among the 160 patients, 84 (52.5%) were boys and 76 (47.5%) were girls, and the mean age was 85.95 ± 49.03 months (9-188 months). Of the 160 patients, 66 (41.3%) were treated with monotherapy, and 94 (58.8%) with polytherapy. We detected increased CPK concentration or rhabdomyolysis in three patients (1.9%). The CPK values of these three patients were 943, 1504, and 5046, respectively. No significant differences were observed in the serum CPK concentration between the patients treated with LEV. CONCLUSION: We detected that LEV may cause increased CPK concentration or rhabdomyolysis. When treating patients with LEV, clinicians should closely monitor serum CPK level. To the best of our knowledge, this is the first study of elevated CPK concentration or rhabdomyolysis associated with LEV therapy in children.

Clinical Features and Molecular Genetics of Autosomal Recessive Ataxia in the Turkish Population.

BACKGROUND: Autosomal recessive cerebellar ataxias (ARCAs) are a heterogeneous group of inherited neurodegenerative disorders. The aim of this study was to present the clinical and genetic features of patients with ataxia complaints and those genetically diagnosed with ARCAs. MATERIALS AND METHODS: Thirty-one children with ARCA were retrospectively analyzed. RESULTS: Fourteen (45.2%) were boys and 17 (54.8%) were girls with the mean age at onset of symptoms of 46.13 ± 26.30 months (12-120 months). Of the 31 patients, 21 (67.7%) were from consanguineous marriages. Eight patients had Friedreich's ataxia, five had ataxia telangiectasia, three had L-2-hydroxyglutaric aciduria, three had Joubert syndrome, two had neuronal ceroid lipofuscinosis, two had megalencephalic leukoencephalopathy with subcortical cysts, two had ataxia with ocular motor oculomotor apraxia type 1, one had cytochrome c oxidase deficiency, one had autosomal recessive spastic ataxia of Charlevoix-Saguenay, one had Niemann-Pick type C, one had congenital disorders of glycosylation, one had adrenoleukodystrophy, and one had cobalamin transport disorder. CONCLUSION: The prevalence of hereditary ataxia can vary among countries. The consanguineous marriage is an important finding in these diseases. These genetic tests will increase the number of ARCA patients diagnosed.

Mitochondrial Membrane Protein-Associated Neurodegeneration: A Case Series of Six Children.

Neurodegeneration with brain iron accumulation (NBIA) is a group of genetic disorders with a progressive extrapyramidal syndrome and excessive iron deposition in the brain, particularly in the globus pallidus and substantia nigra. Mitochondrial membrane protein-associated neurodegeneration (MPAN), a subtype of NBIA, is caused by mutation in the orphan gene C19orf12. A slowly progressive gait disorder from generalized dystonia and spasticity and cognitive impairment constitute the main features of MPAN. The C19orf12 p.Thr11Met mutation is frequent among Turkish patients with MPAN. Here, we report the clinical manifestations and genetic study results of six Turkish patients with MPAN due to different mutations from previous.

Different Clinical Manifestations of Three Prime Repair Exonuclease 1 Mutation: A Case Series.

Three prime repair exonuclease 1 (TREX1) degrades single- and double-stranded DNA with 3'-5' exonuclease activity. TREX1 mutations are related to type 1 interferon-mediated autoinflammation owing to accumulated intracellular nucleic acids. Several cases of systemic lupus erythematosus, Aicardi-Goutieres syndrome (AGS), familial chilblain lupus (FCL), and retinal vasculopathy-cerebral leukodystrophy caused by TREX1 mutations have been reported, so far. In this report, we described five patients with TREX1 mutations from three families with three different disorders, which include AGS, FCL, and FCL with central nervous system vasculitis.

Dynamic thiol/disulphide homeostasis in children with Duchenne muscular dystrophy.

Duchenne muscular dystrophy (DMD) is a disorder that alter the expression of the dystrophin protein. Dystrophin deficiency alters the structural integrity of the contractile apparatus/sarcolemmal integrity, leading to dystrophic changes. Dystrophin deficiency results in an increase in oxidative stress. We aimed to investigate the thiol/disulfide balance as an oxidative stress marker in children with DMD. We included 24 DMD, and 22 healthy control group subjects in the study. The total thiol, native thiol, and disulphide levels were measured and the disulphide/native thiol, disulphide/total thiol and native thiol/total thiol ratios were calculated in DMD patients and healthy subjects. The mean age distribution of the patients and the healthy control group subjects was similar. The total thiol, native thiol, and disulfide levels were lower in DMD group than the healthy controls. In conclusion, the markers and ratios were measured and calculated in the blood, and we detected that the total thiol, and native thiol levels were lower in DMD group than the healthy controls. These results indicate that dynamic thiol-disulphide homeostasis can be used as a marker of oxidative stress in clinical trials with DMD.

Autosomal-Recessive Spastic Ataxia of Charlevoix-Saguenay: A Turkish Child.

Autosomal-recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is caused by mutations of the SACS gene, characterized by late-infantile-onset spastic ataxia and other neurological features. ARSACS has a high prevalence in northeastern Quebec, Canada. Recently, several ARSACS cases have been reported from outside Canada. We report typical clinical and neuroimaging features in a Turkish child, which confirmed genetic diagnosis of ARSACS.

Late-Onset Leigh Syndrome due to NDUFV1 Mutation in a 10-Year-Old Boy Initially Presenting with Ataxia.

Leigh syndrome (LS) is a progressive neurodegenerative disease caused by either mitochondrial or nuclear DNA mutations resulting in dysfunctional mitochondrial energy metabolism. The onset of clinical features is typically between 3 and 12 months of age; however, a later onset has been described in a few patients. Complex I deficiency is reported to be the most common cause of mitochondrial disorders. We described a patient with a late-onset LS, who presented with gait ataxia, caused by complex I deficiency (NDUFV1 gene).

Neuro-ichthyotic Syndromes: A Case Series.

BACKGROUND: The neuro-ichthyotic diseases are clinically and genetically heterogeneous. The purpose of this study was to evaluate the clinical and neuroradiological findings and to analyze mutation in 15 patients with neuro-ichthyotic diseases. MATERIALS AND METHODS: We retrospectively analyzed the records of 15 patients with the diagnosis of neuro-ichthyotic diseases. RESULTS: Eight female and seven male patients (age range 11 months-52 years) were investigated. There were eight patients with Sjögren-Larsson syndrome (SLS), five patients with multiple sulfatase deficiency (MSD), one patient with Chanarin-Dorfman's syndrome, and one patient with mental retardation, enteropathy, deafness, neuropathy, ichthyosis, and keratodermia (MEDNIK) syndrome. Parental consanguinity was found in all the patients except one. All patients had ichthyosis. Diagnosis was performed with genetic study. CONCLUSIONS: Because biochemical and clinical findings are variable, the diagnosis is difficult in most of the cases. Detailed skin and physical examinations are mandatory in these patients. Genetic tests are necessary for accurate diagnosis.

Spinocerebellar Ataxia-21 in a Turkish Child.

Hereditary cerebellar ataxias are genetically heterogeneous disorders. Autosomal recessive spinocerebellar ataxia-21 (SCAR21) is a neurologic disorder characterized by the onset of cerebellar ataxia, recurrent episodes of liver failure, peripheral neuropathy, and learning disabilities. Herein, we reported a case presented with gait and balance problems, swallowing difficulties, mild delayed motor development, and mild learning disability with SCAR21 that confirmed by mutation analysis in a Turkish child. To the best of our knowledge, this is the first case of SCAR21 from Turkey.

Autoimmune encephalitis associated with glutamic acid decarboxylase antibodies: a case series.

Antibodies against glutamic acid decarboxylase (GAD) are associated with various neurologic conditions described in patients including stiff person syndrome, cerebellar ataxia, refractory epilepsy, limbic and extralimbic encephalitis. GAD antibodies-related limbic encephalitis cases are well described; reports of extralimbic involvement are limited. We describe four cases of GAD antibody-related autoimmune encephalitis. Three of them had extralimbic involvement and only one had limbic encephalitis.

Guillain-Barré syndrome with hyperreflexia and bilateral papillitis in a child.

Guillain-Barré syndrome (GBS) is an acute inflammatory polyneuropathy characterized by rapidly progressive symmetric weakness, and areflexia. Areflexia is necessary for the diagnosis of GBS. However, recently there have been studies of hyperreflexia with axonal neuropathy form of GBS. We report a 14-year-old boy with GBS, who presented with hyperreflexia and bilateral papillitis. To the best of our knowledge, this is the first pediatric patient presenting with papillitis and hyperreflexia with acute motor and sensory axonal neuropathy form of GBS.

Intravenous levetiracetam in critically ill children.

BACKGROUND: To report the effectiveness and safety of intravenous (IV) levetiracetam (LEV) in the treatment of critically ill children with acute repetitive seizures and status epilepticus (SE) in a children's hospital. MATERIALS AND METHODS: We retrospectively analyzed data from children treated with IV LEV. RESULTS: The mean age of the 108 children was 69.39 ± 46.14 months (1-192 months). There were 58 (53.1%) males and 50 (46.8%) females. LEV load dose was 28.33 ± 4.60 mg/kg/dose (10-40 mg/kg). Out of these 108 patients, LEV terminated seizures in 79 (73.1%). No serious adverse effects were observed but agitation and aggression were developed in two patients, and mild erythematous rash and urticaria developed in one patient. CONCLUSION: Antiepileptic treatment of critically ill children with IV LEV seems to be effective and safe. Further study is needed to elucidate the role of IV LEV in critically ill children.