Ercan Demir

Weight gain associated with valproate in childhood

Weight gain is a common side effect of valproate treatment. Several mechanisms have been suggested for its pathophysiology; of these, impairment of beta-oxidation of fatty acids and increased insulin secretion have been supported by clinical studies. To investigate whether changes in carnitine and insulin levels had a role in the weight gain occurring with valproate treatment in children, 20 patients with epilepsy were randomly assigned to receive either carnitine or placebo supplementation in addition to valproate. After a follow-up period of 3 months, weight gain was observed in both groups. The mean insulin concentration and insulin/glucose ratios increased. Weight gain did not correlate with carnitine levels. These results suggest that weight gain during valproate treatment is not related to a decrease in carnitine levels. However, an increase in insulin levels together with a decrease in glucose levels may cause weight gain, possibly by stimulating appetite.

Molecular Genetic Analysis of the PLP1 Gene in 38 Families with PLP1-related disorders: Identification and Functional Characterization of 11 Novel PLP1 Mutations

BackgroundThe breadth of the clinical spectrum underlying Pelizaeus-Merzbacher disease and spastic paraplegia type 2 is due to the extensive allelic heterogeneity in the X-linked PLP1 gene encoding myelin proteolipid protein (PLP). PLP1 mutations range from gene duplications of variable size found in 60-70% of patients to intragenic lesions present in 15-20% of patients.MethodsForty-eight male patients from 38 unrelated families with a PLP1-related disorder were studied. All DNA samples were screened for PLP1 gene duplications using real-time PCR. PLP1 gene sequencing analysis was performed on patients negative for the duplication. The mutational status of all 14 potential carrier mothers of the familial PLP1 gene mutation was determined as well as 15/24 potential carrier mothers of the PLP1 duplication.Results and ConclusionsPLP1 gene duplications were identified in 24 of the unrelated patients whereas a variety of intragenic PLP1 mutations were found in the remaining 14 patients. Of the 14 different intragenic lesions, 11 were novel; these included one nonsense and 7 missense mutations, a 657-bp deletion, a microdeletion and a microduplication. The functional significance of the novel PLP1 missense mutations, all occurring at evolutionarily conserved residues, was analysed by the MutPred tool whereas their potential effect on splicing was ascertained using the Skippy algorithm and a neural network. Although MutPred predicted that all 7 novel missense mutations would be likely to be deleterious, in silico analysis indicated that four of them (p.Leu146Val, p.Leu159Pro, p.Thr230Ile, p.Ala247Asp) might cause exon skipping by altering exonic splicing elements. These predictions were then investigated in vitro for both p.Leu146Val and p.Thr230Ile by means of RNA or minigene studies and were subsequently confirmed in the case of p.Leu146Val. Peripheral neuropathy was noted in four patients harbouring intragenic mutations that altered RNA processing, but was absent from all PLP1-duplication patients. Unprecedentedly, family studies revealed the de novo occurrence of the PLP1 duplication at a frequency of 20%.

3-Methylcrotonyl-CoA carboxylase deficiency: phenotypic variability in a family.

A family with 3-methylcrotonyl-CoA carboxylase deficiency with different clinical features is described. A 15-month-old boy, who was the index patient, was admitted to the hospital with atonic seizure. His brother had delayed language development and their uncle had been followed with diagnosis of epilepsy for the last 5 years. Urinary organic acid analysis displayed elevated 3-hydroxyisovaleric acid and 3-methylcrotonylglycine, analysis of acylcarnitines showed elevated 3-hydroxyisovalerylcarnitine and decreased free carnitine levels in both the patients and their uncle. Methylcrotonyl-CoA carboxylase activity in cultured fibroblasts displayed a low residual activity of 2.2% of the median control value while propionyl-CoA carboxylase activity was normal in the index patient. Mutation analysis revealed a large homozygous deletion of 2264 bp (c.873+4524_6787de12264) in the MCCA gene, which has not been described to date. Adult-onset afebrile seizures have not been reported in the literature. Our cases are an example of this wide phenotypic variability within a single family.

Reduced Retinal Nerve Fiber Layer Thickness and Macular Volume in Pediatric Multiple Sclerosis

Retinal atrophy is well known in adult-onset multiple sclerosis but remains unexplored in children. We aimed to determine retinal nerve fiber layer thickness and macular volume in pediatric patients, with and without optic neuritis and their relations with visual evoked potentials. We also examined macular volume changes at month 12. Retinal nerve fiber layer thickness of all quadrants and macular volume were measured in 28 relapsing remitting multiple sclerosis eyes and 30 control eyes using optical coherence tomography and were found reduced in patients compared with controls. This reduction was more prominent in eyes with longer time interval from optic neuritis. Retinal nerve fiber thickness was lower in eyes with delayed visual evoked potentials. Visual evoked potential amplitudes were reduced in affected eyes compared to patients without optic neuritis. Macular volume reduced nonsignificantly in patients at month 12. Retinal atrophy occurs in pediatric multiple sclerosis, and previous optic neuritis accelerates this atrophy.

Homozygous Mutations in TBC1D23 Lead to a Non-degenerative Form of Pontocerebellar Hypoplasia

Pontocerebellar hypoplasia (PCH) represents a group of recessive developmental disorders characterized by impaired growth of the pons and cerebellum, which frequently follows a degenerative course. Currently, there are 10 partially overlapping clinical subtypes and 13 genes known mutated in PCH. Here, we report biallelic TBC1D23 mutations in six individuals from four unrelated families manifesting a non-degenerative form of PCH. In addition to reduced volume of pons and cerebellum, affected individuals had microcephaly, psychomotor delay, and ataxia. In zebrafish, tbc1d23 morphants replicated the human phenotype showing hindbrain volume loss. TBC1D23 localized at the trans-Golgi and was regulated by the small GTPases Arl1 and Arl8, suggesting a role in trans-Golgi membrane trafficking. Altogether, this study provides a causative link between TBC1D23 mutations and PCH and suggests a less severe clinical course than other PCH subtypes.

An unusual presentation of Muscle–Eye–Brain disease: Severe eye abnormalities with mild muscle and brain involvement

Muscle-eye-brain disease (MEB) is characterised by congenital muscular dystrophy, structural brain malformations and eye abnormalities. We report a MEB case whose presenting sign was congenital blindness. She was investigated primarily for eye abnormalities at onset. She had bilateral retinal detachment and microphthalmia. Mild axial hypotonia and motor retardation were attributed to cerebral disorder in another center. Muscle biopsy showed mild myopathic changes and significant alpha-dystroglycan deficiency. Analysis of the POMGnT1 showed a novel homozygous mutation 1814G>C, causing p.Arg605Pro change. This case expands the clinical spectrum of MEB with unusually severe eye abnormalities compared to mild skeletal muscle and brain involvement.

Opsoclonus-myoclonus syndrome following rotavirus gastroenteritis.

Opsoclonus–myoclonus syndrome (OMS) is a rare neurologic disorder characterized by opsoclonus, myoclonus, ataxia and behavioral disturbance. In the pathogenesis, an autoimmune process with infectious or paraneoplastic trigger has been suggested. We describe the case of a 22‐month‐old girl with OMS following rotavirus gastroenteritis. Rotavirus should be considered in the differential diagnosis of OMS in children.

Does Nephrotoxicity Exist in Pediatric Epileptic Patients on Valproate or Carbamazepine Therapy

The aim of this study was to investigate the effects of valproate and carbamazepine, on renal glomerular and tubular functions. The patient group comprised 54 children with new-onset epilepsy treated with valproate (n = 30) and carbamazepine (n = 24). Twenty-six healthy children were in the control group. The serum creatinine and cystatin C levels and urinary excretion of N-acetyl-β-d-glucosaminidase (NAG) levels were measured and the glomerular filtration rate (GFR) was estimated. Serum creatinine and cystatin C concentrations were not different between patients and controls. The glomerular filtration rate of the patient groups were higher than those of the control group. Thus, both drugs probably lead to glomerular hyperfiltration and toxicity for glomerular functions. However, urinary N-acetyl-β-d-glucosaminidase/creatinine levels were significantly higher in patients receiving only valproate (6.1 ± 5). The difference between carbamazepine and control groups was not significant for urinary N-acetyl-β-d-glucosaminidase/creatinine levels. Our data suggest that valproate has adverse effects on renal tubular functions.

Atypical Presentations of Subacute Sclerosing Panencephalitis in Two Neurologically Handicapped Cases

Subacute sclerosing panencephalitis (SSPE) is a neurodegenerative disorder caused by persistent measles infection. Here, we report two neurologically handicapped cases presenting with atypical features of SSPE. Patient 1 who had mild mental retardation manifested acute encephalopathy with partial seizures and hemiplegia, mimicking encephalitis. He showed a fulminant course without myoclonia or a periodic electroencephalogram complex. Although SSPE is usually associated with an increased diffusion pattern, diffusion-weighted imaging of our patient showed decreased diffusion in the right hippocampus. Patient 2 with infantile hemiparesis presented with secondary generalized seizures, followed by asymettrical myoclonias involving the side contralateral to the hemiparesis. A periodic electroencephalogram complex was absent on the previously damaged brain regions. Our findings show that preexisting neurological disorders may modify the clinical or electrophysiological findings of SSPE, leading to atypical presentations. SSPE should be considered in the differential diagnosis of acute encephalopathy with lateralizing signs or unidentified seizures. Decreased diffusion resolution in diffusion-weighted-imaging may correlate with rapid clinical progression in SSPE.

Multiple Sclerosis with Onset Younger Than 10 Years in Turkey

Abstract Objective To identify the demographics, clinical characteristics, disease course, treatment patterns, and disability levels of multiple sclerosis (MS) patients with onset under the age of 10 years (early onset multiple sclerosis, EOMS). Methods EOMS patients were reviewed retrospectively in detailed records from 27 child neurology centers. Patients with preschool (≤7 years) and school age (>7 years) onset were compared. Results There were 30 children (16 girls, 14 boys) who have disease onset between 4 and 10 (mean8.1 ± 1.8) years. MS was relapsing‐remitting in 29 (96.7%) and primary progressive in one (3.3%) of the patients. In patients with onset ≤7 years, motor symptoms (54.5%) and encephalopathy (45.5%) predominated, while in those with onset >7 years brainstem (42.1%), sensory (26.3%), and optic nerve (26.3%) involvement were the most frequent presentations. Conclusions MS starting ≤7 years differs from the 7‐10‐year‐old group by the higher rate of motor symptoms and more attacks in the first year: the latter suggests a more inflammatory character for EOMS.