OBJECTIVE:We aimed to delineate the clinical and genetic spectrum of ATP1A3-related disorders and recognition of a potential genotype-phenotype correlation.
METHODS:We identified 16 new patients with ...alternating hemiplegia of childhood (AHC) and 3 new patients with rapid-onset dystonia-parkinsonism (RDP) and included these as well as the clinical and molecular findings of all previously reported 164 patients with mutation-positive AHC and RDP in our analyses.
RESULTS:Major clinical characteristics shared in common by AHC and RDP comprise a strikingly asymmetric, predominantly dystonic movement disorder with rostrocaudal gradient of involvement and physical, emotional, or chemical stressors as triggers. The clinical courses include an early-onset polyphasic for AHC, a later-onset mono- or biphasic for RDP, as well as intermediate forms. Meta-analysis of the 8 novel and 38 published ATP1A3 mutations shows that the ones affecting transmembrane and functional domains tend to be associated with AHC as the more severe phenotype. The majority of mutations are located in exons 8, 14, 17, and 18.
CONCLUSION:AHC and RDP constitute clinical prototypes in a continuous phenotypic spectrum of ATP1A3-related disorders. Intermediate phenotypes combining criteria of both conditions are increasingly recognized. Efficient stepwise mutation analysis of the ATP1A3 gene may prioritize those exons where current state of knowledge indicates mutational clusters.
Abstract To describe the clinical and neurophysiological spectrum and prognosis in a large cohort of biochemically and genetically proven late onset Pompe patients. Thirty-eight diagnosed with late ...onset Pompe disease at our neuromuscular department during 1985 and 2006 are described in detail. The mean delay from onset of symptoms or first medical consultation until diagnosis was 10.4 and 7.1 years, respectively. A different diagnosis was suggested in 11 of 38 patients. Ten patients underwent repeated muscle biopsies before diagnosis of Pompe disease was established. Limb girdle weakness was the most frequent presenting sign. Six patients complained of myalgia. Wolf–Parkinson–White syndrome was found in 3 of 38 patients. Respiratory failure preceded the onset of overt limb muscle weakness in three patients. The course of the patients was progressive in all, but there was a wide variety of progression, which did not correlate with the age of disease onset. In 71% of the patients, neurophysiological investigations revealed a myopathic EMG pattern, half of the patients had spontaneous activity including complex repetitive discharges. A normal EMG was found in 9% of the patients. Nerve conduction studies were normal in all. Pompe disease should be taken into consideration in patients with unexplained limb girdle muscular weakness with respiratory failure. Cardiac manifestations may not be restricted to infantile Pompe disease.
Abstract Objective This is the first study to validate and to compare the Children's Depression Inventory (CDI) and its short version (CDI:S) as screening tools for medically ill children. Methods A ...sample of 406 pediatric hospital patients, aged 9 to 12 years (56.2% male, 77.1% inpatients), completed the German CDI. Criterion validity of the 26-item CDI and the 10-item CDI:S was calculated by receiver operating characteristic (ROC) curves. DSM-IV diagnoses of depression based on the structured diagnostic interview for mental disorders in children and adolescents (Kinder-DIPS) served as the reference standard. Areas under the ROC curves as well as sensitivities and specificities for the optimal cutoffs were compared for both versions. Results Diagnoses of major or minor depression were established for 7.4% of the children. Areas under the curve for the 26-item CDI (87.7%) and the 10-item CDI:S (88.2%) were comparable. For the CDI, the cutoff ≥ 12 yielded the best balance between sensitivity (83.3%) and specificity (82.7%). At the optimal cutoff ≥ 3, the CDI:S resulted in a high sensitivity of 93.3% and a specificity of 70.7%. Thus, the CDI:S proved to be as sensitive as the CDI, but was less specific than the full-length version. Conclusion Both the CDI and the CDI:S are valid screening instruments for depression in medically ill children. The sensitive and brief CDI:S is a promising tool in time-pressed settings such as pediatric care, but has to be followed by a thorough diagnostic assessment to rule out false positive cases.
Vitamin-B
-dependent epilepsies are a heterogenous group of treatable disorders due to mutations in several genes (
or
). In neonatal seizures, defects in
explain a major fraction of cases. Very ...recently biallelic mutations in
were shown to be a novel cause in five families. We identified four further unrelated patients harbouring a total of six different mutations, including four novel disease mutations. Vitamin B
plasma profiles on pyridoxine did not enable the differentiation of patients with
mutations. All four patients were normocephalic and had normal cranial imaging. Pyridoxine monotherapy allowed complete seizure control in one, while two patients had occasional febrile or afebrile seizures and one needed additional valproate therapy for photosensitive seizures. Two patients underwent a controlled pyridoxine withdrawal with signs of encephalopathy within a couple of days. Three had favourable outcome with normal intellectual properties at age 12.5, 15.5 and 30 years, respectively, while one child had marked developmental delay at age 27 months. The clinical and electroencephalographic phenotype in patients with
mutations was indistinguishable from
and
deficiency. We therefore confirm
as a novel gene for vitamin-B
-dependent epilepsy and delineate a non-specific plasma vitamin B
profile under pyridoxine treatment.
Abstract Mutations in the ATP1A3 gene are associated with rapid-onset dystonia-parkinsonism (RDP) and alternating hemiplegia of childhood (AHC) as well as RDP/AHC intermediate presentations. ...Phenotypic diversity is being recognized. In order to identify ATP1A3-related phenotypes not meeting the classical criteria for RDP or AHC we lowered the threshold for mutation analysis in clinical presentations resembling AHC or RDP. A novel heterozygous ATP1A3 missense mutation c.2600G > A (p.Gly867Asp, G867D) was detected in a 15-year-old girl. Her clinical phenotype is partially consistent with an intermediate presentation between alternating hemiplegia of childhood and rapid-onset dystonia-parkinsonism and comprises additional yet unreported features. With onset at 4½ years of age recurrent paroxysmal flaccid hemiplegia alternating in laterality was triggered by watching television or playing computer games. Occlusion of both eyes reliably stopped the plegic attacks with the patient remaining awake. Our observation further widens the phenotypic spectrum associated with ATP1A3 mutations.
The study aimed at widening the clinical and genetic spectrum and assessing genotype–phenotype associations in FOXG1 syndrome due to FOXG1 variants.
We compiled 30 new and 53 reported patients with a ...heterozygous pathogenic or likely pathogenic variant in FOXG1. We grouped patients according to type and location of the variant. Statistical analysis of molecular and clinical data was performed using Fisher’s exact test and a nonparametric multivariate test.
Among the 30 new patients, we identified 19 novel FOXG1 variants. Among the total group of 83 patients, there were 54 variants: 20 frameshift (37%), 17 missense (31%), 15 nonsense (28%), and 2 in-frame variants (4%). Frameshift and nonsense variants are distributed over all FOXG1 protein domains; missense variants cluster within the conserved forkhead domain. We found a higher phenotypic variability than previously described. Genotype–phenotype association revealed significant differences in psychomotor development and neurological features between FOXG1 genotype groups. More severe phenotypes were associated with truncating FOXG1 variants in the N-terminal domain and the forkhead domain (except conserved site 1) and milder phenotypes with missense variants in the forkhead conserved site 1.
These data may serve for improved interpretation of new FOXG1 sequence variants and well-founded genetic counseling.
Neurodevelopmental disorders (NDD) caused by protein phosphatase 2A (PP2A) dysfunction have mainly been associated with de novo variants in PPP2R5D and PPP2CA, and more rarely in PPP2R1A. Here, we ...aimed to better understand the latter by characterizing 30 individuals with de novo and often recurrent variants in this PP2A scaffolding Aα subunit.
Most cases were identified through routine clinical diagnostics. Variants were biochemically characterized for phosphatase activity and interaction with other PP2A subunits.
We describe 30 individuals with 16 different variants in PPP2R1A, 21 of whom had variants not previously reported. The severity of developmental delay ranged from mild learning problems to severe intellectual disability (ID) with or without epilepsy. Common features were language delay, hypotonia, and hypermobile joints. Macrocephaly was only seen in individuals without B55α subunit-binding deficit, and these patients had less severe ID and no seizures. Biochemically more disruptive variants with impaired B55α but increased striatin binding were associated with profound ID, epilepsy, corpus callosum hypoplasia, and sometimes microcephaly.
We significantly expand the phenotypic spectrum of PPP2R1A-related NDD, revealing a broader clinical presentation of the patients and that the functional consequences of the variants are more diverse than previously reported.
Congenital mirror movements (CMM) are involuntary movements of one side of the body that mirror intentional movements of the other side. Heterozygous missense, frameshift and nonsense variants and ...small intragenic deletions in DCC cause CMM, isolated agenesis of the corpus callosum (ACC) or both. We report here the clinical phenotype and natural history of ten individuals with CMM carrying five different monoallelic DCC variants, including the missense variant p.(Trp273Arg), two duplications, one deletion and one deletion-insertion; all are novel and absent from databases. We re-evaluated the 15 known disease-associated DCC missense variants by determining minor allele frequency (MAF) and pathogenicity using four in silico tools combining previous pathogenicity scores and the ACMG/AMP standards and guidelines and classified them in three groups. Group I contains three DCC missense variants that are rather unlikely to be associated with a higher risk to CMM and/or ACC. The five variants in group II may represent susceptibility factors to altered midline crossing in the central nervous system. Group III includes seven variants absent in publically available databases and representing possible pathogenic alleles, with four predicted to have a severe impact on protein function. Based on this data and the variable expressivity and incomplete penetrance present in heterozygous carriers of a DCC variant, classification and clinical interpretation of missense variants is challenging in the absence of evidence of pathogenicity originated from functional studies. Evaluation of missense variants by MAF and a weighted combination of several computational algorithms is recommended.
•EEG data from a randomized controlled trial in children with BECTS.•No significant differences between Sulthiame or Levetiracetam.•Persistent EEG pathologies associated with an increased risk for ...recurrent seizures.
BECTS (benign childhood epilepsy with centrotemporal spikes) is associated with characteristic EEG findings. This study examines the influence of anti-convulsive treatment on the EEG.
In a randomized controlled trial including 43 children with BECTS, EEGs were performed prior to treatment with either Sulthiame or Levetiracetam as well as three times under treatment. Using the spike-wave-index, the degree of EEG pathology was quantified. The EEG before and after initiation of treatment was analyzed. Both treatment arms were compared and the EEG of the children that were to develop recurrent seizures was compared with those that were successfully treated.
Regardless of the treatment agent, the spike-wave-index was reduced significantly under treatment. There were no differences between the two treatment groups. In an additional analysis, the EEG characteristics of the children with recurrent seizures differed statistically significant from those that did not have any further seizures.
Both Sulthiame and Levetiracetam influence the EEG of children with BECTS. Persistent EEG pathologies are associated with treatment failures.
Leukoencephalopathy with vanishing white matter, also called “childhood ataxia with central nervous system hypomyelination,” is the first human disease related to mutations in any of the five genes ...encoding subunits of eukaryotic initiation factor eIF2B or any translation factor at all. eIF2B is essential in all cells of the body for protein synthesis and the regulation of this protein synthesis under different stress conditions. It is surprising that mutations in the eIF2B genes have been reported to lead to abnormalities of the white matter of the brain only, although it has been shown recently that ovarian failure may accompany the leukoencephalopathy. Another surprising observation is that the onset of the disease varies from early childhood to adulthood, with the exception of Cree leukoencephalopathy, a disease related to a particular mutation in one of the eIF2B genes, which invariably has its onset within the first year of life. We analyzed the eIF2B genes of nine patients with an antenatal- or early-infantile–onset encephalopathy and an early demise and found mutations in eight of the patients. In addition to signs of a serious encephalopathy, we found oligohydramnios, intrauterine growth retardation, cataracts, pancreatitis, hepatosplenomegaly, hypoplasia of the kidneys, and ovarian dysgenesis. Until now, no evidence had been found for a genotype-phenotype correlation, but the consistently severe phenotype in affected siblings among our patients and in Cree encephalopathy patients suggests an influence of the genotype on the phenotype.
PDF
