Clinical features and magnesium levels: Novel insights in 15q11.2 BP1-BP2 copy number variants.

BACKGROUND: Investigating copy number variations (CNVs) such as microdeletions or microduplications can significantly contribute to discover the aetiology of neurodevelopmental disorders. 15q11.2 genomic region, including NIPA1 and NIPA2 genes, contains a recurrent but rare CNV, flanked by the break points BP1 and BP2. Both BP1-BP2 microdeletion and microduplication have been associated with intellectual disability (ID), neuropsychiatric/behavioural disturbances and mild clinical features, even if with incomplete penetrance and variable expressivity. The pathogenic role of this CNV is quite unclear though. Unknown variants in other DNA regions and parent-of-origin effect (POE) are some of the mechanisms that have been proposed as an explanation of the wide phenotypic variability. As NIPA1 and NIPA2 encode for proteins that mediate magnesium (Mg2+ ) metabolism, it has been suggested that urinary Mg2+ levels could potentially represent informative and affordable biomarkers for a rapid screening of 15q11.2 duplications or deletions. Furthermore, magnesium supplementation has been proposed as possible therapeutic strategy. METHODS: Thirty one children with ID and/or other neurodevelopmental disorders carrying either a duplication or a deletion in 15q11.2 BP1-BP2 region have been recruited. When available, blood samples from parents have been analysed to identify the CNV origin. All participants underwent family and medical data collection, physical examination and neuropsychiatric assessment. Electroencephalogram (EEG) and brain magnetic resonance imaging (MRI) scan were performed in 15 children. In addition, 11 families agreed to participate to the assessment of blood and urinary Mg2+ levels. RESULTS: We observed a highly variable phenotypic spectrum of developmental issues encompassing ID in most subjects as well as a variety of behavioural disorders such as autism and attention-deficit disorder/attention-deficit hyperactivity disorder. Dysmorphic traits and malformations were detected only in a minority of the participants, and no clear association with growth anomalies was found. Abnormal brain MRI and/or EEG were reported respectively in 64% and 92% of the subjects. Inheritance assessment highlighted an excess of duplication of maternal origin, while cardiac alterations were detected only in children with 15q11.2 CNV inherited from the father. We found great variability in Mg2+ urinary values, without correlation with 15q11.2 copy numbers. However, the variance of urinary Mg2+ levels largely increases in individuals with 15q11.2 deletion/duplication. CONCLUSIONS: This study provides further evidence that 15q11.2 BP1-BP2 CNV is associated with a broad spectrum of neurodevelopmental disorders and POE might be an explanation for clinical variability. However, some issues may question the real impact of 15q11.2 CNV on the phenotype in the carriers: DNA sequencing could be useful to exclude other pathogenic gene mutations. Our results do not support the possibility that urinary Mg2+ levels can be used as biomarkers to screen children with neurodevelopmental disorders for 15q11.2 duplication/deletion. However, there are evidences of correlations between 15q11.2 BP1-BP2 CNV and Mg2+ metabolism and future studies may pave the way to new therapeutic options.

Comprehensive molecular screening strategy of OCLN in band-like calcification with simplified gyration and polymicrogyria.

Occludin (OCLN) is an important component of the tight junction complex, providing apical intercellular connections between adjacent cells in endothelial and epithelial tissue. In 2010 O'Driscoll et al reported mutations in OCLN to cause band-like calcification with simplified gyration and polymicrogyria (BLC-PMG). BLC-PMG is a rare autosomal recessive syndrome, characterized by early onset seizures, progressive microcephaly, severe developmental delay and deep cortical gray matter and basal ganglia calcification with symmetrical, predominantly fronto-parietal, polymicrogyria. Here we report 4 additional cases of BLC-PMG with novel OCLN mutations, and provide a summary of the published mutational spectrum. More generally, we describe a comprehensive molecular screening strategy taking into account the technical challenges associated with the genetic architecture of OCLN, which include the presence of a pseudo-gene and copy number variants.

Supratentorial and pontine MRI abnormalities characterize recessive spastic ataxia of Charlevoix-Saguenay. A comprehensive study of an Italian series.

BACKGROUND AND PURPOSE: The autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is an early-onset neurodegenerative disorder caused by mutations in the SACS gene. The disease, first described in Canadian families from Québec, is characterized by cerebellar ataxia, pyramidal tract involvement and peripheral neuropathy. METHODS: Analysis of SACS gene allowed the identification of 14 patients with ARSACS from 13 unrelated Italian families. Clinical phenotype, gene mutations and magnetic resonance imaging (MRI) findings were analysed. RESULTS: We found 16 novel SACS gene mutations, including a large in-frame deletion. The age at onset was in infancy, but one patient presented the first symptoms at age 32. Progression of the disease was variable, and increased muscle tone was mostly recognized in later stages. Structural MRI showed atrophy of the superior cerebellar vermis, a bulky pons exhibiting T2-hypointense stripes, identified as the corticospinal tract (CST), thinning of the corpus callosum and a rim of T2-hyperintensity around the thalami in 100% of cases. The presence of iron or other paramagnetic substances was excluded. Diffusion tensor imaging (DTI) revealed grossly over-represented transverse pontine fibres (TPF), which prevented reconstruction of the CST at this level (100% of cases). In all patients, significant microstructural alterations were found in the supratentorial white matter of forceps, cingulum and superior longitudinal fasciculus. CONCLUSIONS: Our findings further enlarge the genetic spectrum of SACS mutations and widen the study of clinical phenotype. MRI characteristics indicate that pontine changes and supratentorial abnormalities are diagnostic. The over-representation of TPF on DTI suggests a developmental component in the pathogenesis of the disease.

The "eye-of-the-tiger" sign may be absent in the early stages of classic pantothenate kinase associated neurodegeneration.

Pantothenate kinase-associated neurodegeneration (PKAN) is a rare disorder associated with brain iron accumulation. The brain MRI abnormality consists of T2 hypointensity in the globus pallidus with a small hyperintensity in its medial part, called the "eye-of-the-tiger" sign. We report on 2 patients affected by PKAN, in whom MRI examination did not demonstrate the "eye-of-the-tiger" sign in the early stages; the typical abnormalities were detected only in the following examinations. Case 1 is a 4-year-old boy first studied at age 2 years for psychomotor delay. The brain MRI was normal. In the following 2 years, the motor impairment progressed. The second brain MRI at age 4 years demonstrated the "eye-of-the-tiger" sign. Molecular analysis of the PANK2 gene revealed a missense mutation F228S in exon 2 in homozygosis. Case 2 is a 6-year-old boy first studied at age 2 years because of psychomotor delay. His brain MRI did not demonstrate abnormalities in the globus pallidus. In the following years spastic-dystonic tetraparesis became evident. A brain MRI at age 4 years demonstrated the "eye-of-the-tiger" sign. Molecular analysis of the PANK2 gene revealed a missense mutation in exon 5 (N501I). Our 2 cases demonstrate that the observation of a normal globus pallidus in the early stage of the disease does not exclude the diagnosis of classic PKAN.

Oxidative stress in resuscitation and in ventilation of newborns.

The lungs of newborns are especially prone to oxidative damage induced by both reactive oxygen and reactive nitrogen species. Yet, these infants are often 1) exposed to high oxygen concentrations, 2) have infections or inflammation, 3) have reduced antioxidant defense, and 4) have high free iron levels which enhance toxic radical generation. Oxidative stress has been postulated to be implicated in several newborn conditions with the phrase "oxygen radical diseases of neonatology" having been coined. There is, however, reason to believe that oxidative stress is increased more when resuscitation is performed with pure oxygen compared with ambient air and that the most effective ventilatory strategy is the avoidance of mechanical ventilation with the use of nasopharyngeal continuous positive airway pressure whenever possible. Multiple ventilation strategies have been attempted to reduce injury and improve outcomes in newborn infants. In this review, the authors summarise the scientific evidence concerning oxidative stress as it relates to resuscitation in the delivery room and to the various modalities of ventilation.

Band-like intracranial calcification with simplified gyration and polymicrogyria: a distinct "pseudo-TORCH" phenotype.

The combination of intracranial calcification and polymicrogyria is usually seen in the context of intrauterine infection, most frequently due to cytomegalovirus. Rare familial occurrences have been reported. We describe five patients-two male-female sibling pairs, one pair born to consanguineous parents, and an unrelated female-with a distinct pattern of band-like intracranial calcification associated with simplified gyration and polymicrogyria. Clinical features include severe post-natal microcephaly, seizures and profound developmental arrest. Testing for infectious agents was negative. We consider that these children have the same recognizable "pseudo-TORCH" phenotype inherited as an autosomal recessive trait.

Papillitis as an onset sign of Leber's hereditary optic neuropathy: a case report.

Leber's hereditary optic neuropathy is a maternally transmitted disease resulting from a point mutation in mitochondrial (mt) DNA. In this report we describe a case of Leber's disease with typical clinical findings but atypical ophthalmoscopic presentation. A 14-year-old boy developed severe loss of vision acuity in the left eye, with only partial recovery, followed 4 months later by the same symptoms in the right eye. Fundoscopic examination showed hyperemic papilla on the right eye and optic disc pallor on the left eye. Polymerase chain reaction analysis of lymphocytic mt-DNA revealed a point mutation at 11778. Leber's disease should be considered in young patients (not always male) with sudden visual loss and simple papillary involvement at fundoscopic examination but without the typical telangiectatic microangiopathy.

A case of 3-methylglutaconic aciduria misdiagnosed as cerebral palsy.

3-Methylglutaconic aciduria is a rare hereditary metabolic disorder characterized by increased urinary excretion of 3-methylglutaconic and 3-methylglutaric acids. Four clinical forms are recognized. This study presents the case of a 5-year-old male with type IV 3-methylglutaconic aciduria, initially diagnosed as "static encephalopathy." The slow evolution and other clinical characteristics, together with cerebral magnetic resonance imaging (MRI) findings, eventually directed the diagnosis to organic aciduria that was confirmed by urine test. This study proposes that the clinical criteria for childhood cerebral palsy should be rigorously respected; neuroimaging studies, particularly MRI, should be conducted to confirm the diagnosis, especially in atypical cases.

Clinical characteristics of adolescent headache.

We evaluate clinical characteristics of headache in a group of subjects > 12 years to assess the sensitivity and specificity of the IHS criteria. We consider whether age at onset may influence the clinical features. We used a semi-structured questionnaire to examine 136 patients consecutively referred to our division. We considered the following subdiagnoses: IHS 1.1, 1.2, 1.7, 2.1, 2.2, 2.3. Migrainous disorders were found to be more common than non-migrainous headaches. A definite diagnosis was established in 68.1% of the migrainous group and in 86.6% of the tension-type headache group. Unilateral location, severe intensity of pain, the presence of nausea, vomiting, phonophobia and photophobia were features which differed between migrainous and non-migrainous subjects. No difference was found regarding aggravation of the headache by physical activity. On the basis of the criterion duration of attacks < 2 hours, IHS 1.7 was found to differ significantly from other migraine types. With the exception of the presence of vomiting in migrainous patients, the age at onset was not found to be a factor influencing the characteristics of the headache. Diagnostic criteria for migraine were highly specific but poorly sensitive, and those for tension-type headaches highly sensitive but less specific. The sensitivity/specificity of the IHS criteria in adolescent migraine can be influenced by the heterogeneity of the clinical characteristics. In fact, the intensity, the location and the quality of pain were similar to those found in childhood migraine, while the concomitant symptoms were less frequent than in childhood and in adult migraine. Further studies are needed to define the degree of severity of the clinical features in adolescent headache and to address the question of the validity of the IHS criteria.

Management of oxygen and carbon dioxide pressure after cardiac arrest.

Experimental evidence shows that derangements of arterial partial pressures of either oxygen (PaO2) and carbon dioxide (PaCO2) immediately after resuscitation from cardiac arrest may increase the severity of organ dysfunction due to whole body ischemia and subsequent reperfusion. Hyperoxia is believed to increase reperfusion injury, especially to mitochondrial membrane due to increased production of reactive oxygen species. Two large observational studies in human adults showed that hyperoxia (defined as a PaO2≥300 mmHg) in the first 24 h after hospital admission was associated with increased mortality or lower likelihood of independent functional status at hospital discharge. Evidence of the effects of hyperoxia in children were less consistent. A reduction of PaCO2 below normal values may cause cerebral vasoconstriction and increase the severity of delayed brain hypopefusion which usually occurs within 24h from resuscitation. Cerebrovascular reactivity to CO2 is preserved during therapeutic hypothermia. According to recent clinical studies, a low PaCO2 after resuscitation is associated with increased mortality and higher rates of poor neurological outcome both in children and in adults, while the effects of a PaCO2 above 45 mmHg are less clear. The PaCO2 derangements are very common in resuscitated patients. Maintaining normal levels of both PaO2 and PaCO2 and in particular avoiding both hyperoxia and hypocapnia may reduce morbidity and improve survival of cardiac arrest survivors. Available clinical evidence is however almost exclusively limited to observational studies which may be biased by potential uncontrolled confounders.

Novel POMGNT1 point mutations and intragenic rearrangements associated with muscle-eye-brain disease.

Congenital muscular dystrophies due to defects in genes encoding proteins involved in α-dystroglycan (α-DG) glycosylation are a heterogeneous group of muscle disorders variably associated with central nervous system and eye abnormalities. One of the more severe is muscle-eye-brain disease (MEB). Mutations in genes coding for proven or putative glycosyltransferases (POMT1, POMT2, POMGnT1, fukutin, FKRP, and LARGE), the DPM3 gene encoding a DOL-P-Man synthase subunit, and the DAG1 gene encoding α-dystroglycan, have been associated with altered α-DG glycosylation. We report new POMGnT1 mutations and evaluate protein expression in 3 patients and 2 foetuses with variably severe MEB features. We identify two new point mutations (c.643C>T, c.1863delC), one new intragenic rearrangement (deletion of exons 2-8), and a new intron retention (between exons 21 and 22) resulting from a known point mutation c.1895+1G>T. Our study provides further evidence that rearrangements of the POMGnT1 gene are relatively common. Importantly, if heterozygous, they can be missed on standard genomic DNA sequencing. POMGNT1 protein analysis in 3 patients showed that the severity of the phenotype does not correlate with protein expression. Cerebral MRI is important for identifying MEB and α-dystroglycanopathy phenotypes in children and foetuses, and hence for directing the genetic analysis.

The effectiveness of hospitalization in the treatment of paediatric idiopathic headache patients.

BACKGROUND: Headache is a disease that has a high social impact in the paediatric as well as in the adult population, often resulting in a significant reduction in the young patient's quality of life, reflected primarily in a greater number of days off school and increasingly frequent recourse to symptomatic drugs. The idea for this study came from the clinical impression that some paediatric headache patients might benefit more from inpatient than outpatient care. AIM: The aim of our study was to compare the effectiveness of hospitalization to outpatient care of patients with newly diagnosed frequent and disabling headache. METHODS: A pragmatic randomized open-label trial was conducted at the Child Neurology Clinic of the University of Pavia, Italy. Children and adolescents with a 2- to 6-month moderate-to-severe migraine or tension-type headache history were randomized to hospital admission or outpatient assessment and followed for 6 months. The efficacy of the two therapeutic strategies was measured by counting the number of responders in each arm. Other end points included the mean frequency and duration of attacks, the number of drug prescriptions taken to control pain, and the number of patients and physicians expressing satisfaction with treatment. RESULTS: The study population included 27 girls and 23 boys aged 8 through 18 years with migraine (23 cases) or tension-type headache (27 cases). Compared to outpatient assessment, hospital admission was correlated to a significant increase in the number of responders: 0 vs. 44% (1 month), 0 vs. 68% (3 months), and 12 vs. 68% (6 months). The mean frequency and duration of attacks were significantly lower in hospitalized patients (p < 0.0001). Hospitalization was correlated with a significant reduction of patients with severe headache (p < 0.005), a reduction of drug use, and a higher number of satisfied patients and physicians (p < 0.05). Logistic regression analysis confirmed the higher responder rate among hospitalized patients after adjusting for age, sex, diagnosis, and headache characteristics or admission. CONCLUSIONS: We think hospitalization reduces the emotional mechanisms that provoke stress in children and often induce or favour headache attacks. If these mechanisms can be interrupted, the management of disease may become easier and with enduring benefits.

Cognitive and behavioural effects of migraine in childhood and adolescence.

Since cognitive and behavioural characteristics of paediatric migraine sufferers have yet to be adequately defined, in this study we assessed the effect of migraine on the interictal functioning of children and adolescents by comparing the performance of two patient groups, 17 migraine sufferers with aura (MA) and 31 without aura (MoA) and by correlating the duration of the disorder, the frequency of attacks and interictal period with neuropsychological and behavioural findings. Both patient groups had cognitive performance within normal range except for a significant delay in the reaction time (RT) task. Both MA and MoA revealed a behavioural phenotype characterized by internalizing problems on Child Behaviour Check List (CBCL) scales. Slower RT to simple visual stimuli may be an early sign of a subclinical neuropsychological dysfunction, significantly correlated with the frequency of headache attacks and interictal period. The lack of a control group and other methodological limitations, such as patient selection bias and unadjusted P-value for multiple testing, make it difficult to give this finding a clearcut meaning. Further studies are needed on larger samples compared with a control group.

The natural history of Aicardi-Goutières syndrome: follow-up of 11 Italian patients.

Described are the outcomes of 11 Italian patients with Aicardi-Goutières syndrome. Neurologic symptoms progressed in the first year of life and stabilized by the end of the second year in 10 patients. White matter abnormalities remained stable; cerebral atrophy was stable in four patients and progressive in two. Calcifications increased (in number and size) in two of six patients. Serial CSF and serum interferon-alpha measurements (three patients) showed reduced CSF interferon-alpha levels.

Unilateral frontal lobe epilepsy affects executive functions in children.

Very few studies to date have investigated the neuropsychological changes detectable in children suffering from frontal lobe epilepsy (FLE). The aim of the present study was to assess the effects of FLE on cognitive and executive functions in childhood. The sample includes 17 children with a frontal epileptogenic focus (10 right and 7 left), with no evidence of anatomical brain damage. These subjects were assessed by means of a battery of tests to investigate executive functioning. The results emphasised the presence of selective impairments of frontal lobe functions without evidence of deficits in global intellectual functioning. No side-specific deficits were detected, while an earlier onset of epilepsy and the duration of the disorder, but not the seizures frequency, were found to correspond with more severe deficits in some specific frontal lobe functions.

Personality traits in childhood and adolescent headache.

We evaluate personality traits, anxiety and depression in a population of paediatric and adolescent patients, correlating personality characteristics with headache and sociodemographic variables. The clinical features of headache include specific personality traits. We report a clinical study of 57 patients (age 8-18 years), divided up as follows: 12 migraine with aura, 29 migraine without aura and 16 tension-type headache. One of Cattel's tests was administered to every patient; the Children's Depression Inventory test was administered to 53 patients and the Test Anxiety Inventory test to 43 subjects. The scores obtained by every patient in each test were correlated with the characteristics of headache and with sociodemographic data. We found that patients affected by idiopathic headache share some personality traits, mainly emotional rigidity and tendency to repress anger and aggression. These traits do not seem to be correlated with sociodemographic data and the duration of headache: we considered these as characteristic of migrainous patients.

Are vascular disorders more prevalent in the relatives of children and adolescents with migraine?

The objective of the study was to assess whether a family history of vascular disorders is more common in children and adolescents with migraine than in the general population. Family history of stroke, arterial hypertension, myocardial infarction and diabetes was investigated by history taking in relatives of ambulatory children and young adults with migraine and in a control group. The odds ratios (ORs) with 95% confidence intervals (95% CI) were used as a risk measure. Using univariate and multivariate (logistic regression) analysis, family history was assessed in the whole sample and in subgroups by sex and age, degree of relationship (parents and grandparents vs. relatives), disease type (migraine with and without aura), and type of vascular disorder. The sample included 143 cases (migraine with aura 35, migraine without aura 108) and 164 controls aged 3-24 years (mean 12 +/- 3.8 years). Patients with migraine were at increased risk of vascular disorders in parents and grandparents but not in all relatives. Multivariate analysis indicated family history of stroke as most common only in boys. In conclusion, our study provides some clues to the assumption that migraine and vascular disorders have common pathogenic mechanisms and that genetic susceptibility plays a role in increasing the risk of migraine in the offspring of families with one or more cerebrovascular or cardiovascular conditions.