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Mild Mental Retardation (mild + mental_retardation)
Selected AbstractsAetiology in severe and mild mental retardation: a population-based study of Norwegian childrenDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2 2000Petter Strømme MD PhD The aetiology of mental retardation (MR) was studied in a population-based series of Norwegian children derived from 30 037 children born between 1980 and 1985. The study included 178 children, 79 with severe MR (SMR) (IQ<50) and 99 with mild MR (MMR) (IQ 50 to 70). Aetiology was divided into two main groups: biopathological and unspecified. The biopathological group comprised 96% of SMR and 68% of MMR, and was subdivided into prenatal (70% and 51%), perinatal (4% and 5%), and postnatal damage (5% and 1%), and a group of undetermined timing of the damaging event (18% and 11%). Single-gene disorders accounted for 15 of the 63 children with genetic disorders, including X-linked recessive in six. During the course of the study, at least 27 (15%) children had their aetiological diagnosis revised. Gestational age <32 weeks, birthweight <1500g, and Apgar scores 0 to 2 at 1 and 5 minutes implied a significantly increased risk of MR, but contributed to only 4% of the children in the study. Decreased birthweight (1500 to 2499 g) and Apgar scores 3 to 6 at 1 and 5 minutes showed increased probability of MR. Despite extensive investigations, 4% of SMR and 32% of MMR were not identified with any biological markers and were considered as unspecified MR, several most probably representing the lower end of the normal IQ distribution in the population. [source] An interstitial deletion of the long arm of chromosome 21 in a case of a first episode of psychosisACTA PSYCHIATRICA SCANDINAVICA, Issue 1 2002J. Takhar Objective:,Case of an interstitial deletion of the long arm of chromosome 21 presenting with first episode of psychosis. Method:,A case report. Results:,A 16-year-high school student of Somalian origin presented with a first episode of psychosis, mild mental retardation and dysmorphic features. Chromosome analysis revealed an interstitial deletion in the long arm of chromosome 21, described as 46, XX del (21) (q21q22.1). Conclusion:,First episode of psychosis occurred in combination with neurobiological vulnerability and a complex genetic inheritance. The occurrence of psychosis in our case may be attributable to genes located within the region 21q21q22.1. The possibility that other loci exist on chromosome 21, which predispose to schizophrenia has to be considered. Identification of susceptibility genes will greatly facilitate investigation of factors that contribute to the disease process and may lead to early intervention and prevention. [source] Mild Generalized Epilepsy and Developmental Disorder Associated with Large Inv Dup(15)EPILEPSIA, Issue 9 2002Rosanna Chifari Summary: ,Purpose: Several studies attempted to clarify the genotype,phenotype correlations in patients with inverted duplication of chromosome 15 [inv dup(15)], which is usually characterized by severe mental retardation and epilepsy in individuals with large duplications including the Prader,Willi/Angelman region. We report two patients with inv dup(15) who, in spite of a large duplication, had a mild phenotype including adult-onset epilepsy. This report may help to define the milder spectrum of the syndrome. Methods: A 25-year-old girl with mild mental retardation had a 6-year history of absence seizures, with occasional head drop. Interictal EEG revealed diffuse spike,wave complexes. Epilepsy was well controlled by a combination of lamotrigine (LTG) and valproate (VPA). The other patient, a 27-year-old man with mild mental retardation, had a 5-year history of rare generalized tonic,clonic seizure during sleep, and frequent episodes of unresponsiveness, which appeared to be atypical absence seizures on video-EEG recordings. A combination of VPA and LTG led to a remarkable improvement, although no complete control. Results: Molecular analysis revealed a large inv dup15 in both patients. Conclusions: The discrepancy between the mild phenotype and the severe chromosomal abnormality detected in these two patients further supports the notion that the site of breakpoint might be contributory to the inv dup(15) phenotype. Inv dup(15) should be considered in atypical cases of generalized epilepsy of adult onset without clear-cut etiology. [source] Electroclinical Picture of Autosomal Dominant Nocturnal Frontal Lobe Epilepsy in a Japanese FamilyEPILEPSIA, Issue 1 2000Masatoshi Ito Summary: Purpose: Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is the first described partial epilepsy syndrome known to be due to a single gene mutation. We found a first Japanese ADNFLE family with a novel mutation of the neuronal nicotinic acetylcholine receptor (nAChR) ,4 subunit (CHRNA4) gene. The aim of this report is precisely to describe the electroclinical manifestations of ADNFLE in this family and to compare these findings with those of other families reported previously in the literature. Methods: Three affected family members were investigated electroclinically by close clinical observation, interictal EEG, video-EEG monitoring, magnetic resonance imaging, and single-photon-emission tomography. Information about other affected family members was obtained from either the spouse or the parents. Mutations within the CHRNA4 gene were examined in seven family members. Results: The clinical manifestations and diagnostic findings in the members of this family were consistent with ADNFLE. However, there were intrafamilial and interfamilial variations in clinical features. The seizures of the patients were brief tonic seizures, with hyperventilation in children and secondarily generalized tonic,clonic convulsions in adults. The onset of the children's seizures began in infancy and early childhood. The children's seizures were sometimes provoked by movement and sound stimulation, and did not respond to antiepileptic drugs. On the other hand, the adults' seizures disappeared spontaneously or were easily controlled with carbamazepine. Three children showed hyperactivity, and two children had mild mental retardation. All patients had impaired consciousness during their seizures and no auras. A novel missense mutation (c755C>T) in exon 5 of the CHRNA4 gene was found in four affected family members. Conclusions: The electroclinical pictures of a Japanese family with ADNFLE were basically the same as those of other families reported, but with slight differences. ADNFLE is probably not uncommon, and it is very likely that there are unidentified patients with this inherited disorder in Japan. [source] Myotonia and muscle contractile properties in mice with SIX5 deficiencyMUSCLE AND NERVE, Issue 4 2005Kirkwood E. Personius PhD Abstract Myotonic dystrophy (DM1) is an autosomal-dominant multisystem disease characterized by progressive skeletal muscle weakness, myotonia, cataracts, cardiac arrhythmias, mild mental retardation, and endocrinopathies. Heterozygous loss of SIX5 in mice causes cataracts and cardiac conduction disease, and homozygous loss also leads to sterility and decreased testicular mass, reminiscent of DM1 in humans. The effect of SIX5 deficiency in muscle is unknown. In this study, we found that muscle contractile properties, electromyographic insertional activity, and muscle histology were normal in SIX5 deficient mice. The implications of these findings for the pathogenesis of DM1 are discussed. Muscle Nerve, 2004 [source] Patterns of dysmorphic features in schizophrenia,AMERICAN JOURNAL OF MEDICAL GENETICS, Issue 8 2001L.E. Scutt Abstract Congenital dysmorphic features are prevalent in schizophrenia and may reflect underlying neurodevelopmental abnormalities. A cluster analysis approach delineating patterns of dysmorphic features has been used in genetics to classify individuals into more etiologically homogeneous subgroups. In the present study, this approach was applied to schizophrenia, using a sample with a suspected genetic syndrome as a testable model. Subjects (n,=,159) with schizophrenia or schizoaffective disorder were ascertained from chronic patient populations (random, n,=,123) or referred with possible 22q11 deletion syndrome (referred, n,=,36). All subjects were evaluated for presence or absence of 70 reliably assessed dysmorphic features, which were used in a three-step cluster analysis. The analysis produced four major clusters with different patterns of dysmorphic features. Significant between,cluster differences were found for rates of 37 dysmorphic features (P,<,0.05), median number of dysmorphic features (P,=,0.0001), and validating features not used in the cluster analysis: mild mental retardation (P,=,0.001) and congenital heart defects (P,=,0.002). Two clusters (1 and 4) appeared to represent more developmental subgroups of schizophrenia with elevated rates of dysmorphic features and validating features. Cluster 1 (n,=,27) comprised mostly referred subjects. Cluster 4 (n,=,18) had a different pattern of dysmorphic features; one subject had a mosaic Turner syndrome variant. Two other clusters had lower rates and patterns of features consistent with those found in previous studies of schizophrenia. Delineating patterns of dysmorphic features may help identify subgroups that could represent neurodevelopmental forms of schizophrenia with more homogeneous origins. © 2001 Wiley-Liss, Inc. [source] Nonsyndromic mental retardation and cryptogenic epilepsy in women with Doublecortin gene mutationsANNALS OF NEUROLOGY, Issue 1 2003Renzo Guerrini MD DCX mutations cause mental retardation in male subjects with lissencephalypachygyria and in female subjects with subcortical band heterotopia (SBH). We observed four families in which carrier women had normal brain magnetic resonance imaging (MRI) and mild mental retardation, with or without epilepsy. Affected male subjects had SBH or pachygyria-SBH. In two families, the phenotype was mild in both genders. In the first family, we found a tyr138his mutation that is predicted to result in abnormal folding in the small hinge region. In the second family, we found an arg178cys mutation at the initial portion of R2, in the putative ,-sheet structure. Carrier female subjects with normal MRI showed no somatic mosaicism or altered X-inactivation in lymphocytes, suggesting a correlation between mild mutations and phenotypes. In the two other families, with severely affected boys, we found arg76ser and arg56gly mutations within the R1 region that are predicted to affect DCX folding, severely modifying its activity. Both carrier mothers showed skewed X-inactivation, possibly explaining their mild phenotypes. Missense DCX mutations may manifest as non-syndromic mental retardation with cryptogenic epilepsy in female subjects and SBH in boys. Mutation analysis in mothers of affected children is mandatory, even when brain MRI is normal. Ann Neurol 2003 [source] Prompting procedures as establishing operations for escape-maintained behaviorBEHAVIORAL INTERVENTIONS, Issue 1 2006Jennifer L. Crockett In the current study, we report on a young man with Nager's Syndrome, mild mental retardation, and deafness who exhibited severe problem behavior during demand situations. Initial functional analysis suggested that problem behavior was maintained by gaining escape from instructional demands. However, further analysis suggested that the individual was responding to escape the prompting procedure rather than the work tasks themselves. Copyright © 2006 John Wiley & Sons, Ltd. [source] Borderline intellectual functioning in children and adolescents , insufficiently recognized difficultiesACTA PAEDIATRICA, Issue 5 2010Elisabeth Fernell Abstract Aim:, To draw attention to groups of children and adolescents with borderline intellectual functioning, especially with respect to their school-situation. Methods:, In one study, population-based, children with borderline intellectual functioning at age 10 years were followed until they finished compulsory school when their final certificates could be analysed. In a second study parents of 20 individuals in the upper secondary school for pupils with mild mental retardation were interviewed according to the Vineland adaptive scales and school health records were reviewed. In a third study pupils attending an individual programme in upper secondary school were assessed and we report one representative case. Results:, (1) Pupils with borderline intellectual functioning, assessed in grade 4, received significantly lower grades when finishing the compulsory school. (2) In the group of pupils in the upper secondary school for the mildly mentally retarded, compiled data indicated that a considerable number did not fulfil the combined IQ and adaptive criteria for mild mental retardation. (3) The subtle nature of borderline intellectual functioning may delay appropriate measures at school, which our case illustrates. Conclusion:, Borderline intellectual functioning seldom attracts attention. Our studies indicate that school and also society at large must be prepared to adapt educational and working conditions for the large minority of individuals with borderline intellectual functioning. [source] Burden of disease attributable to selected environmental factors and injury among children and adolescents in EuropeCHILD: CARE, HEALTH AND DEVELOPMENT, Issue 6 2004Richard Reading Burden of disease attributable to selected environmental factors and injury among children and adolescents in Europe . ValentF, LittleD, BertolliniR, NemerLE, BarboneF & TamburliniG . ( 2004 ) Lancet , 363 , 2032 , 2039 . Background Environmental exposures contribute to the global burden of disease. We have estimated the burden of disease attributable to outdoor and indoor air pollution, inadequate water and sanitation, lead exposure, and injury among European children and adolescents. Methods Published studies and reports from international agencies were reviewed for calculation of risk-factor exposure in Europe. Disability-adjusted life years (DALYs) or deaths attributable to each factor, or both, were estimated by application of the potential impact fraction to the estimates of mortality and burden of disease from the WHO global database of burden of disease. Findings Among children aged 0,4 years, between 1.8% and 6.4% of deaths from all causes were attributable to outdoor air pollution; acute lower-respiratory-tract infections attributable to indoor air pollution accounted for 4.6% of all deaths and 3.1% of DALYs; and mild mental retardation resulting from lead exposure accounted for 4.4% of DALYs. In the age-group 0,14 years, diarrhoea attributable to inadequate water and sanitation accounted for 5.3% of deaths and 3.5% of DALYs. In the age-group 0,19 years, injuries were the cause of 22.6% of all deaths and 19.0% of DALYs. The burden of disease was much higher in European subregions B and C than subregion A. There was substantial uncertainty around some of the estimates, especially for outdoor air pollution. Interpretation Large proportions of deaths and DALYs in European children are attributable to outdoor and indoor air pollution, inadequate water and sanitation, lead exposure, and injuries. Interventions aimed at reducing children's exposure to environmental factors and injuries could result in substantial gains. The pronounced differences by subregion and age indicate the need for targeted action. [source] Complex epileptic (Foix,Chavany,Marie like) syndrome in a child with neurofibromatosis type 1 (NF1) and bilateral (opercular and paracentral) polymicrogyriaACTA PAEDIATRICA, Issue 4 2009Mario Mastrangelo Abstract The association of brain malformations and symptomatic epilepsy in the setting of neurofibromatosis type 1 (NF1) is rarely reported. When it occurs, patients can present clinically with infantile spasms, focal seizures, generalized tonic clonic seizures or atypical absences. We report on a 10-year-old (molecularly proven) NF1 girl manifesting a complex epileptic syndrome resembling the Foix,Chavany,Marie spectrum (also known as opercular syndrome) associated with bilateral (opercular and paracentral lobular) polymicrogyria (PMG). Anecdotal cases of unilateral PMG in the setting of NF1 have been described in association with other-than-opercular epileptic syndromes. The typical clinical opercular syndrome consisting in mild mental retardation, epilepsy and pseudobulbar palsy is usually associated to bilateral perisylvian PMG (BPP) Conclusion: To the best of our knowledge, the complex epileptic syndrome hereby reported has not been previously recorded in the setting of NF1. In addition, the present girl manifested all the clinical features of an opercular syndrome but had an asymmetrical PMG (not a BPP). [source] Neuronal migration disorders: clinical, neuroradiologic and genetics aspectsACTA PAEDIATRICA, Issue 3 2009Alberto Spalice Disorders of neuronal migration are a heterogeneous group of disorders of nervous system development. One of the most frequent disorders is lissencephaly, characterized by a paucity of normal gyri and sulci resulting in a ,smooth brain'. There are two pathologic subtypes: classical and cobblestone. Six different genes could be responsible for this entity (LIS1, DCX, TUBA1A, VLDLR, ARX, RELN), although co-delection of YWHAE gene with LIS1 could result in Miller,Dieker Syndrome. Heterotopia is defined as a cluster of normal neurons in abnormal locations, and divided into three main groups: periventricular nodular heterotopia, subcortical heterotopia and marginal glioneural heterotopia. Genetically, heterotopia is related to Filamin A (FLNA) or ADP-ribosylation factor guanine exchange factor 2 (ARFGEF2) genes mutations. Polymicrogyria is described as an augmentation of small circonvolutions separated by shallow enlarged sulci; bilateral frontoparietal form is characterized by bilateral, symmetric polymicrogyria in the frontoparietal regions. Bilateral perisylvian polymicrogyria results in a clinical syndrome manifested by mild mental retardation, epilepsy and pseudobulbar palsy. Gene mutations linked to this disorder are SRPX2, PAX6, TBR2, KIAA1279, RAB3GAP1 and COL18A1. Schizencephaly, consisting in a cleft of cerebral hemisphere connecting extra-axial subaracnoid spaces and ventricles, is another important disorder of neuronal migration whose clinical characteristics are extremely variable. EMX2 gene could be implicated in its genesis. Focal cortical dysplasia is characterized by three different types of altered cortical laminations, and represents one of most severe cause of epilepsy in children. TSC1 gene could play a role in its etiology. Conclusion: This review reports the main clinical, genetical and neuroradiological aspects of these disorders. It is hoped that accumulating data of the development mechanisms underlying the expanded network formation in the brain will lead to the development of therapeutic options for neuronal migration disorders. [source] | ||||||||||