Polymorphisms of Immunoglobulin G Fc Receptors in Pediatric Guillain-Barré Syndrome.

Introduction Guillain-Barré syndrome (GBS) is an autoimmune peripheral neuropathy characterized by demyelination and axonal damage. Biallelic functional polymorphisms in the immunoglobulin G Fc receptors (FcγR)-FcγRIIA: H131/R131, FcγRIIIA: V158/F158, and FcγRIIIB: NA1/NA2 affect the affinity of the IgG-FcγR interaction, therefore, diseases such as GBS in which this interaction plays a critical role might be influenced by the polymorphisms. Methods We evaluated the role of FcγR polymorphisms in susceptibility to GBS in Egyptian pediatric patients and the association of the variant alleles with neurophysiological types, severity, and outcome of the disease. A total of 50 patients with GBS and 50 controls were examined for FcγR polymorphisms by allele-specific polymerase chain reaction. Results FcγRIIA H131 allele (p = < 0.0001; odds ratio [OR] = 4.78; 95% confidence interval [CI], 2.62-8.70) and FcγRIIA H/H131 genotype (p = < 0.0001 ; OR = 10.56; 95% CI, 3.59-31.06) were significantly increased in GBS patients while FcγRIIIA and FcγRIIIB allelic distributions were similar among patients and controls. The FcγR genotypes showed no association with neurophysiological types of GBS, severity or outcome of the disease. Conclusions These findings reflect that FcγRIIA H131 allele may represent a risk marker for susceptibility to GBS.

Skeletal and cardiac muscle involvement in children with glycogen storage disease type III.

UNLABELLED: Glycogen storage disease type III (GSD III) may present with hepatic disease or may involve both skeletal and cardiac muscles as well. To assess the prevalence of neuromuscular and cardiac involvement in a group of children with GSD III, 28 children with GSD III, diagnosed by enzymatic assay, were enrolled in the study after an informed consent was obtained from their parents/guardians and after the study protocol was approved by our institutional ethical committee. Their mean age was 6.6 + 3.1 years. All cases were assessed neurologically by clinical examination, electromyography (EMG), and nerve conduction velocity. The heart was examined clinically by electrocardiogram and echocardiography. Seventeen patients (61 %) had myopathic changes by EMG, three of them had associated neuropathic changes. Creatine phosphokinase (CPK) was elevated in all myopathic cases except one. Children with myopathic changes were significantly older (p = 0.02), and CPK was significantly higher (p < 0.0001). Nine cases had left ventricular (LV) hypertrophy, seven of them had myopathic changes by EMG. CONCLUSION: Myopathic changes are not uncommon in children with GSD III. Myopathic changes tend to occur in older age and are associated with higher CPK level. Cardiac muscle involvement is less common in this age group and may, on occasion, occur alone without skeletal muscle involvement. Despite mild degrees of affection in this age group, it is recommended to perform prospective annual screening using EMG and echocardiography in order to augment dietary therapy regimen to prevent progression to life threatening complications.

PRRT2 mutations: exploring the phenotypical boundaries.

BACKGROUND: Mutations in the proline-rich transmembrane protein 2 (PRRT2) gene have been identified in patients with benign (familial) infantile convulsions (B(F)IC), infantile convulsions with choreoathetosis (ICCA) and paroxysmal dyskinesias (PDs). However it remains unknown whether PRRT2 mutations are causal in other epilepsy syndromes. After we discovered a PRRT2 mutation in a large family with ICCA containing one individual with febrile seizures (FS) and one individual with West syndrome, we analysed PRRT2 in a heterogeneous cohort of patients with different types of infantile epilepsy. METHODS: We screened a cohort of 460 patients with B(F)IC or ICCA, fever related seizures or infantile epileptic encephalopathies. All patients were tested for point mutations using direct sequencing. RESULTS: We identified heterozygous mutations in 16 individuals: 10 familial and 6 sporadic cases. All patients were diagnosed with B(F)IC, ICCA or PD. We were not able to detect mutations in any of the other epilepsy syndromes. Several mutation carriers had learning disabilities and/or impaired fine motor skills later in life. CONCLUSIONS: PRRT2 mutations do not seem to be involved in the aetiology of FS or infantile epileptic encephalopathies. Therefore B(F)IC, ICCA and PD remain the core phenotypes associated with PRRT2 mutations. The presence of learning disabilities or neuropsychiatric problems in several mutation carriers calls for additional clinical studies addressing this developmental aspect in more detail.

Cerebral Folate Transport Deficiency in 2 Cases with Intractable Myoclonic Epilepsy.

Cerebral folate transport deficiency due to folate receptor 1 gene (FOLR1) gene mutation results from impaired folate transport across the blood: choroidplexus: cerebrospinal fluid (CSF) barrier. This leads to low CSF 5-methyltetrahydrofolate, the active folate metabolite. We are reporting two children with this treatable cerebral folate transport deficiency. Eight years and 9-month-old female presented with delayed milestones followed by regression, seizures, and intention tremors. On examination child had microcephaly, generalized hypotonia, hyperreflexia, unsteady gait, and incoordination. Magnetic resonance imaging (MRI) of brain revealed dilated ventricular system and cerebellar atrophy. Computed tomography (CT) of brain showed brain calcifications. Whole exome sequencing was finally performed, revealing homozygous nonsense pathogenic variant in FOLR1 gene in exon 3 c.C382T p.R128W, confirming the diagnosis of cerebral folate deficiency. Twelve-year-old female child presented with global developmental delay since birth, myoclonic jerks and cognitive regression. Child had generalized hypotonia and hyperreflexia. Her coordination was markedly affected with intention tremors andunbalanced gait. CT brain showed bilateral basal ganglia and periventricular calcifications with brain atrophic changes. MRI brain showed a prominent cerebellar folia with mild brain atrophic changes. Genetic testing showed a homozygous pathogenic variant was identified in FOLR1 C.327_328 delinsAC, p.Cys109Ter. Both patients were started on intramuscular folinic acid injections with a decrease in seizure frequency. However, their seizures did not stop completely due to late initiation of therapy. In conclusion, cerebral folate transport deficiency should be suspected in every child with global developmental delay, intractable myoclonic epilepsy, ataxia with neuroimaging suggesting cerebellar atrophy and brain calcifications. Response to folinic acid supplementation is partial if diagnosed late and treatment initiation is delayed.

Initial levetiracetam versus valproate monotherapy in antiseizure medicine (ASM)-naïve pediatric patients with idiopathic generalized epilepsy with tonic-clonic seizures.

INTRODUCTION: Levetiracetam (LEV) is a second-generation antiseizure medicine (ASM) with broad-spectrum efficacy and tolerability. Few studies have compared the efficacy of valproate (VPA) and LEV as monotherapy in the pediatric population. Herein, we compare the efficacy, tolerability and safety of LEV monotherapy with those of VPA monotherapy in ASM-naïve pediatric patients with idiopathic generalized epilepsy with tonic-clonic (GTC) seizures. METHODS: We retrospectively analyzed the clinical and electroencephalographic (EEG) data of these ASM-naïve pediatric patients who were treated with either oral VPA or oral LEV as monotherapy for over 2 years at our center. RESULTS: This study included 60 patients with a seizure onset age between 2 months and 12 years. The patients on VPA (29 patients) and LEV monotherapy (31 patients) showed similar favorable 6-month treatment outcomes (complete seizure control in 79.31% vs 80.64%, p = 0.468052). Age at epilepsy onset, epilepsy syndrome, EEG features and ASM dose were not significant predictors of the 6-month treatment outcomes in either group. Lower seizure frequency at presentation was a predictor of favorable 6-month treatment outcomes in the LEV group but not in the VPA group. VPA and LEV treatment showed similar favorable 6-month treatment outcomes in the febrile seizures plus and patients with unidentified epilepsy syndrome subgroups. None of the patients discontinued VPA or LEV due to treatment-associated adverse effects. DISCUSSION: Our study showed that compared to VPA monotherapy, LEV monotherapy in ASM-naïve infants and children with idiopathic generalized epilepsy with GTC seizures has a similarly favorable efficacy and tolerability, independent of age, EEG features and epilepsy syndrome.

Lysosomal Storage Disorders in Egyptian Children.

OBJECTIVE: To describe the spectrum, relative prevalence and molecular background of lysosomal storage disorders in Egypt. METHODS: The authors evaluated the selective screening program for the diagnosis of lysosomal storage disorders in Egyptian children presenting to the inherited metabolic disease unit at Cairo University Children's Hospital, the largest tertiary care pediatric hospital in Egypt, over a six-year period (April 2008 through April 2014). During this period, 1,065 suspected children were assessed clinically, biochemically and some genetically. RESULTS: Two hundred and eleven children (aged 44 ± 32 mo; 56 % boys, 82 % with consanguineous parents) were confirmed with 21 different lysosomal disorders. The diagnostic gap ranged between 2 mo and 14 y (average 25 mo). Mucopolysaccharidoses were the most common group of diseases diagnosed (44.5 %), while Maroteaux-Lamy, Gaucher and nephropathic cystinosis were the most commonly detected syndromes (17.1, 14.7 and 13.7 %, respectively). Eighty mutant alleles and 17 pathogenic mutations were detected in 48 genetically assessed confirmed patients (30 Gaucher, 16 cystinosis and two Niemann-Pick type C patients). CONCLUSIONS: This report is the first to describe relative frequency and spectrum of clinical and molecular data in a large cohort of Egyptian lysosomal patients. The crude estimate denotes that over 80 % of Egyptian lysosomal patients do not have access to optimal diagnosis. Upgrading diagnostic and genetic services for lysosomal storage disorders in Egypt is absolutely necessary.

Inborn errors of metabolism detectable by tandem mass spectrometry in Egypt: The first newborn screening pilot study.

OBJECTIVES: To estimate the burden of metabolic disorders detectable by tandem mass spectrometry in Egypt, through a pilot expanded newborn screening programme at Cairo University Children's Hospital in 2008, and examining the results of 3,900 clinically at-risk children, investigated at Cairo University Children's Hospital for the same disorders over the past 7 years using the same technology. METHODS: Dried blood spots of 25,276 healthy newborns from three governorates in Upper, Middle, and Lower Egypt were screened, to give a representative sample of the Egyptian newborn population. Based on the pilot study outcomes and the results of clinically suspected children, we estimated the total birth prevalence of tandem mass spectrometry detectable metabolic disorders, and the relative frequency of several individual disorders. RESULTS: Among the healthy newborns, 13 metabolic disorder cases (five phenylketonuria [1:5,000], two methylmalonic acidemia, and isovaleric acidemia [1:12,500], one each of maple syrup urine disease, propionic acidemia, ß-ketothiolase deficiency, and primary carnitine deficiency [1:25,000]) were confirmed, giving a total birth prevalence of 1:1944 live births. Among the clinically suspected children, 235 cases were diagnosed, representing a much wider disease spectrum. CONCLUSIONS: Egypt has one of the highest reported birth prevalence rates for metabolic disorders detectable by tandem mass spectrometry. Early diagnosis and management are crucial for the survival and well-being of affected children. A nationwide NBS programme by tandem mass spectrometry is recommended.

Selective screening for inborn errors of metabolism by tandem mass spectrometry in Egyptian children: a 5 year report.

OBJECTIVE: In order to enhance awareness and promote registry for inborn errors of metabolism (IEMs) in Egypt, we aimed to evaluate the prevalence and main clinical findings of IEMs detectable by tandem mass spectrometry (MS/MS) among high risk pediatric patients presenting to our tertiary care facility at Cairo University Children's Hospital over a period of 5 years and to compare the disease burden in Egypt in the absence of a national screening program for inherited metabolic disorders with other populations. METHODS: During this period 3380 Egyptian children were suspected of having IEMs based on clinical/laboratory presentation and were analyzed by MS/MS. Confirmatory testing was performed according to flagged analyte by MS/MS using a different sample type such as plasma or urine or by a different technique such as GC/MS. RESULTS: A relatively high number of patients (203/3380 (6%)) were confirmed with 17 different types of IEMs. Averages for age at diagnosis for different disorders ranged from 2.5 months to 6.6 years with general developmental delay and irreversible neurological damage being the most common presenting features (75.9% and 65.5%, respectively). Amino acid disorders (127/203 (62.6%)), mainly phenylketonuria (100/203 (49.3%)), were the most encountered, followed by organic acidemias (69/203 (34%)), while fatty acid oxidation defects (7/203 (3.4%)) were relatively rare. 88% of patients were born to consanguineous parents. CONCLUSIONS: The development of a nationwide screening program for IEMs is mandatory for early detection of these potentially treatable disorders, prompt and properly timed therapeutic intervention and prevention of the devastating neurological outcomes.