Neuropsychological profile in tuberous sclerosis complex: a study of clinical and cognitive variables in a cohort from Brazil.

BACKGROUND: Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder with a wide clinical, cognitive, and behavioral expressivity. OBJECTIVE: To assess the neuropsychological profile of individuals clinically diagnosed with TSC and the factors that could significantly impact their cognitive development. METHODS: A total of 62 individuals with ages ranging from 3 to 38 years were followed up in a tertiary attention hospital in Southern Brazil, and they were assessed using a standard battery and the Vineland Adaptive Behavior Scales, when intellectual disability was observed. RESULTS: History of epilepsy was found in 56 participants (90.3%), and 31 (50%) presented an intellectual disability. Among the other half of TSC individuals without intellectual disability, 8 (12.9%) presented borderline classification, 20 (32.2%) presented average scores, and 3 (4.8%) were above average. In total, 17 participants (27.4%) fulfilled the diagnostic criteria for autism spectrum disorder. The results of the multiple linear regression analysis suggested that seizures, age at diagnosis, visual perception, and general attention significantly impact cognitive performance indexes. CONCLUSION: The present study suggests that the occurrence of epileptic seizures and older age at diagnosis contribute to higher impairment in the domains of cognitive development, underlining the importance of early diagnosis and the prevention of epileptic seizures or their rapid control. The development of attentional skills, visual perception, and executive functions must be followed up.

ANTECEDENTES: O complexo da esclerose tuberosa (CET) é uma doença genética autossômica dominante com ampla expressividade clínica, cognitiva e comportamental. OBJETIVO: Avaliar o perfil neuropsicológico de indivíduos com diagnóstico clínico de CET e os fatores que poderiam impactar significativamente o seu desenvolvimento cognitivo. MéTODOS: Ao todo, 62 indivíduos com idades entre 3 e 38 anos foram acompanhados em um hospital terciário do Sul do Brasil e avaliados por meio de uma bateria padrão e das Escalas de Comportamento Adaptativo Vineland, quando observada deficiência intelectual. RESULTADOS: Encontrou-se histórico de epilepsia em 56 participantes (90,3%) e de deficiência intelectual em 31 (50%). Quanto à outra metade dos indivíduos com CET sem deficiência intelectual, 8 (12,9%) apresentaram classificação limítrofe, 20 (32,2%) apresentaram pontuações médias e 3 (4,8%) estavam acima da média. No total, 17 participantes (27,4%) preenchiam os critérios diagnósticos para o transtorno do espectro autista. Os resultados da análise de regressão linear múltipla sugeriram que as crises epilépticas, a idade ao diagnóstico, a percepção visual e a atenção geral impactam significativamente os índices de desempenho cognitivo. CONCLUSãO: Este estudo sugere que a ocorrência de crises epilépticas e a maior idade ao diagnóstico contribuem para um maior comprometimento nos domínios do desenvolvimento cognitivo, e destaca-se a importância do diagnóstico precoce e da prevenção das crises epilépticas ou do seu rápido controle. O desenvolvimento de habilidades de atenção, percepção visual e funções executivas deve ser acompanhado.

[Social, cognitive and psychomotor development in peruvian children with congenital hypothyroidism]. / Desarrollo social, cognitivo y psicomotor en niños peruanos con hipotiroidismo congénito.

INTRODUCTION: Congenital hypothyroidism (CH) is the most common cause of preventable intellectual disability in the pediatric population. Early diagnosis and treatment during the first month of life are essential to avoid delaying the neuropsychological development of these patients. OBJECTIVE: to describe the social, cognitive, and psychomotor development of children with CH treated at the National Institute of Child Health (INSN) in Lima, Peru. PATIENTS AND METHOD: Retrospective analysis of 26 CH pa tients seen during 2012-2017 at INSN were reviewed. The aspects of neuropsychological development studied were: cognitive development (IQ), social development (social category), and psychomotor development (gait, speech, and chest control). The IQ was classified according to the result of the Weschler IV scale. An analysis was carried out with the Fisher-Freeman-Halton test to verify if there was a difference in the frequency of the variables according to the age of diagnosis and beginning of treatment. RESULTS: Most of the patients presented a borderline IQ (38.5%), the most frequent social category was educable (88.7%), and most of the patients presented delay in developing the speech (88.5%). In the Fisher-Freeman-Halton test, there was only a statistically significant increase in the number of cases of speech delay in patients treated between 22 days and 12 months of age (c2 = 11.246, p = 0.002, V of Cramer = 0.778). CONCLUSION: Neuropsychological developmental delay was more frequent in patients with CH diagnosed and treated after 21 days of age.

Etiology of intellectual disability in individuals from special education schools in the south of Brazil.

BACKGROUND: Intellectual Disability (ID) is characterized by significant limitations that affect intellectual functioning, adaptive behavior, and practical skills which directly interfere with interpersonal relationships and the environment. In Western countries, individuals with ID are overrepresented in the health system, often due to associated comorbidities, and its life-time cost places ID as one of the most expensive conditions of all diagnoses in the International Classification of Diseases. Most of the people affected (75%) live in low-income countries, suffer from malnutrition, lack health care, and do not have access to adequate treatment. The aim of this study was to obtain an estimate of the diagnostic status as well as the prevalence of familial ID among individuals with serious (moderate or severe) ID in a region of the State of Santa Catarina, investigating attendees of special education schools of the Florianópolis Macroregion. METHODS: This was a cross-sectional study conducted between August 2011 and August 2014, through a semi-structured screening questionnaire for the collection of relevant developmental, clinical, familial and educational data, applied in an interview to guardians of students of special education schools of the macroregion of Florianópolis. RESULTS: The participant special schools enrolled close to 1700 students during the study period and the questionnaire was applied to 849 (50.5%). The male to female ratio of the participants was 1.39:1. Clear etiologic explanations were relatively scarce (24%); most diagnoses referring only to the type and the degree of impairment and for the majority (61.4%) the cause was unknown. About half were sporadic cases within their families (considering three generations). For 44.2% at least one other case of an ID-related condition in the extended family was mentioned, with 293 (34.5%) representing potential familial cases. CONCLUSION: Here we describe the epidemiological profile, the available diagnostics, etiology, family history and possible parental consanguinity of participants with ID of special education schools in the South of Brazil. The main results show the need for etiological diagnosis and uncover the relevance of potential hereditary cases in a population where consanguineous unions have a relatively low frequency (0,6%) and highlight the need for public health actions.

Isolated agenesis of the corpus callosum and normal general intelligence development during postnatal life: a case report and review of the literature.

BACKGROUND: Agenesis of the corpus callosum can occur isolated or as part of a complex congenital syndrome. Patients with isolated agenesis of the corpus callosum may present with severe intellectual disability, although a proportion of affected individuals develop normal intelligence. However, even in patients with no apparent deficits, subtle neuropsychological alterations may occur as the cognitive demand increases with age. Hence, patients with this deffect require a strict follow-up during their postnatal life. Thus, physicians require a better knowledge of the cognitive features of agenesis of the corpus callosum to improve their approach to this cerebral malformation. Here, we report an illustrative case of a school-age child with isolated agenesis of the corpus callosum and normal intelligence. We also provide a literature review about the postnatal screening of neurocognitive deficits in patients with agenesis of the corpus callosum. CASE PRESENTATION: An 8-year-old Hispanic boy with total agenesis of the corpus callosum attended for medical follow-up. The defect was identified during the neonatal period by cranial ultrasonography and brain computed tomography scan. However, he did not present any craniofacial or non-cerebral malformation suggestive of a congenital syndrome. Furthermore, he showed no neuropsychiatric disorder or intellectual disability during his early childhood. At the age of 4, he was subjected to a control brain magnetic resonance imaging that showed total agenesis of the corpus callosum and colpocephaly. At his arrival, a neurological examination was normal with no signs of intracranial hypertension. His intelligence quotient was unaltered and he scored normal in the Mini-Mental State Examination test. The literature reviewed here suggested that patients with agenesis of the corpus callosum require a strict neurocognitive follow-up during postnatal life, as they may present neuropsychological deficits during adolescence, when development of the corpus callosum is completed and there is maximum reliance on this structure. Thus, our patient was scheduled for future annual neurocognitive testing. CONCLUSIONS: Isolated agenesis of the corpus callosum is not innocuous, and patients with this defect require a strict neurocognitive follow-up. We provide an informative reference tool useful for the postnatal neuropsychological screening of patients with isolated agenesis of the corpus callosum.

[Fragile X syndrome and other entities associated with the FMR1 gene: Study of 28 affected families]. / Fragilidad del X y otras entidades asociadas al gen FMR1: estudio de 28 familias afectadas.

The fragile X syndrome occurs due to an expansion of CGG trinucleotides, called full mutation, which is found at the Xq27.3 locus of the FMR1 gene. It is the most common cause of inherited intellectual disability. Associated with autistic spectrum disorders in one third of the patients, it affects males with higher prevalence. It also leads to hypermethylation of the gene promoter, silencing it and reducing the expression levels of FMRP, a protein involved in synaptic maturation and plasticity. A lower expansion causes primary ovarian failure syndrome as well as tremor and ataxia syndrome characterized by progressive cerebellar ataxia of late onset and intention tremor. In the present case-control study we analyze the segregation of mutations of the FMR1 gene in different families and the variability of expression that led to the genetic consultation.

El síndrome de fragilidad del cromosoma X es la causa de discapacidad intelectual heredable más frecuente. Asociado a trastornos del espectro autista en un tercio de los pacientes, afecta, con mayor prevalencia, a los varones. Se debe a una expansión de trinucleótidos CGG (citosina, guanina, guanina), llamada mutación completa en el locus Xq27.3 del gen FMR1, que conduce a la hipermetilación en el promotor del gen y reduce los niveles de expresión de FMRP, una proteína implicada en la maduración y plasticidad sináptica. Una expansión menor de CGG es la causa de insuficiencia ovárica primaria y del síndrome de temblor/ataxia asociado a X frágil, caracterizado por ataxia cerebelosa progresiva, de inicio tardío, y temblor de intención. En el presente estudio de serie de casos, se analiza la segregación de mutaciones del gen FMR1 en diferentes familias y la variabilidad de expresión clínica que llevó a la consulta genética.

Novel ANKRD11 gene mutation in an individual with a mild phenotype of KBG syndrome associated to a GEFS+ phenotypic spectrum: a case report.

BACKGROUND: KBG syndrome is a very rare autosomal dominant disorder, characterized by macrodontia, distinctive craniofacial findings, skeletal findings, post-natal short stature, and developmental delays, sometimes associated with seizures and EEG abnormalities. So far, there have been over 100 cases of KBG syndrome reported. CASE PRESENTATION: Here, we describe two sisters of a non-consanguineous family, both presenting generalized epilepsy with febrile seizures (GEFS+), and one with a more complex phenotype associated with mild intellectual disability, skeletal and dental anomalies. Whole exome sequencing (WES) analysis in all the family members revealed a heterozygous SCN9A mutation, p.(Lys655Arg), shared among the father and the two probands, and a novel de novo loss of function mutation in the ANKRD11 gene, p.(Tyr1715*), in the proband with the more complex phenotype. The reassessment of the phenotypic features confirmed that the patient fulfilled the proposed diagnostic criteria for KBG syndrome, although complicated by early-onset isolated febrile seizures. EEG abnormalities with or without seizures have been reported previously in some KBG cases. The shared variant, occurring in SCN9A, has been previously found in several individuals with GEFS+ and Dravet syndrome. CONCLUSIONS: This report describe a novel de novo variant in ANKRD11 causing a mild phenotype of KGB syndrome and further supports the association of monogenic pattern of SCN9A mutations with GEFS+. Our data expand the allelic spectrum of ANKRD11 mutations, providing the first Brazilian case of KBG syndrome. Furthermore, this study offers an example of how WES has been instrumental allowing us to better dissect the clinical phenotype under study, which is a multilocus variation aggregating in one proband, rather than a phenotypic expansion associated with a single genomic locus, underscoring the role of multiple rare variants at different loci in the etiology of clinical phenotypes making problematic the diagnostic path. The successful identification of the causal variant in a gene may not be sufficient, making it necessary to identify other variants that fully explain the clinical picture. The prevalence of blended phenotypes from multiple monogenic disorders is currently unknown and will require a systematic re-analysis of large WES datasets for proper diagnosis in daily practice.

Growth and Intellectual Abilities of Six-Year-Old Children with Congenital Heart Disease.

OBJECTIVE: To determine growth and its relationship to IQ in children with congenital heart disease (CHD) undergoing cardiopulmonary bypass surgery within the first year of life. STUDY DESIGN: Prospective single-center cohort study on 143 children (91 males) with different types of CHD (29 univentricular). Children with recognized genetic disorders were excluded. Growth (weight, height, and head circumference [HC]) was assessed at birth, before surgery, and at 1, 4, and 6 years and compared with Swiss growth charts. IQ was assessed at 6 years using standardized tests. Univariate and multivariable linear regressions were performed to determine predictors of HC and IQ at 6 years. RESULTS: HC at birth was in the low average range (33rd percentile, P = .03), and weight (49th percentile, P = .23) and length (47th percentile, P = .06) were normal. All growth measures declined until the first surgery, with a catch-up growth until 6 years for height (44th percentile, P = .07) but not for weight (39th percentile, P = .003) or for HC (23rd percentile, P < .001). Children undergoing univentricular palliation showed poorer height growth than other types of CHD (P = .01). Median IQ at 6 years was 95 (range 50-135). Lower IQ at 6 years was independently predicted by lower HC at birth, lower socioeconomic status, older age at first bypass surgery, and longer length of intensive care unit stay. CONCLUSIONS: Smaller HC at birth and postnatal factors are predictive of impaired intellectual abilities at school age. Early identification should alert clinicians to provide early childhood interventions to optimize developmental potential.

Intellectual, adaptive and behavioural characteristics in four patients with 18p deletion syndrome.

BACKGROUND: The association of behavioural phenotype assessment with cytogenomic characterisation may provide a better comprehension of genotype-phenotype correlations in syndromes caused by chromosomal abnormalities, such as 18p deletion syndrome. METHOD: We report on four Brazilian patients with 18p deletion syndrome characterised by cytogenomic techniques and detailed neuropsychological evaluation. Intellectual, adaptive and behavioural characteristics were assessed through the Wechsler's Scales, the Vineland-II Scale and the Child Behaviour Checklist, respectively. Socio-economic measures including main caretaker educational level and family income as defined by Brazilian criteria for social class classification were also collected to evaluate a possible contribution of environmental factors in neurocognitive variability. RESULTS: Two out of four patients showed intellectual disability (IQ < 70). Wechsler's scale results suggest that in our sample, interpretation of social situations based on observation of non-verbal behaviour constitute a cognitive strength while judgement of social rules and language skills associated with word knowledge and verbal fluency may be a cognitive weakness. Concerning adaptive behaviour, motor and socialisation domains showed to better develop than communication and daily living skills on the Vineland-II Scale. Only one patient presented internalising behavioural problems based on the Child Behaviour Checklist. Our results also suggested that socio-economic status may contribute to overall patient development. CONCLUSION: Our results suggest that some 18p deletion syndrome patients may present average intellectual performance and that the segment deletion size and some families' socio-economic conditions may influence cognitive development.

Psicosis, Discapacidad intelectual y trastornos conductuales: enfoque biopsicosocial / Psychosis, intellectual disability and behavioral disorders: biopsychosocial approach

Caso Clínico: Mujer, 23 años. Discapacidad intelectual. Asiste a colegio especial (no lee ni escribe). Institucionalizada. Motivo de ingreso: Paciente ingresa en octubre del 2017 traída por carabineros por ser encontrada en la calle bajo el efecto de múltiples sustancias, con ideación suicida. Días antes fue expulsada del hogar por agresión a cuidadoras. Diagnósticos de ingreso: Discapacidad intelectual moderado. Síndrome suicidal, Trastorno por dependencia a drogas. ¿Esquizofrenia hebefrénica? Evolución: Mantiene desajustes conductuales severos fluctuantes, con serias dificultades para manejar la rabia, lo que la lleva a tener conductas hetero y autoagresivas. Plan de tratamiento: Farmacológico (clozapina), Psicológico (TCC), Social (dispositivo adecuado post-alta). Clozapina para trastornos psicóticos en adultos con discapacidad intelectual. El principal riesgo de atribuir alguno de estos comportamientos a una supuesta "psicosis", es el de "medicalizar" y tratar de forma poco acertada. Es importante descartar factores ambientales y del aprendizaje (hábitos y conductas aprendidas, institucionalización, reacciones ante el estrés agudo.) La prevalencia de abuso y dependencia de sustancias en población con DI va desde el 0,5% al 2,6%. Lo cual es menor que la población general. Pacientes con DI y dependencia a drogas se asocia a otras enfermedades psiquiátricas (42-54%). Se ha informado que las personas con discapacidad intelectual en América Latina a menudo están institucionalizadas y escondidas de la sociedad en instalaciones deficientes y superpobladas.

Clinical Case: Female, 23 years old. Intellectual disability. He attends a special school (she does not read or write). Institutionalized. Reason for admission: Patient enters in October 2017 brought by police officers to be found in the street under the effect of multiple substances, with suicidal ideation. Days before she was expelled from the home because of assaulting caregivers. Admission diagnoses: Moderate intellectual disability. Suicidal syndrome, Disorder due to drug dependence. Hebephrenic schizophrenia? Evolution: Maintains fluctuating severe behavioral imbalances, with serious difficulties in managing rage, which leads to hetero and self-aggressive behaviors. Treatment plan: pharmacological (clozapine), Psychological (CBT), Social (adequate post-hospitalization discharge device). Clozapine for psychotic disorders in adults with intellectual disabilities. The main risk of attributing some of these behaviors to a supposed "psychosis" is that of "medicalizing" and dealing inappropriately. It is important to rule out environmental and learning factors (habits and behaviors learned, institutionalization, reactions to acute stress. The prevalence of substance abuse and dependence in the population with ID ranges from 0.5% to 2.6%. Which is less than the general population. Patients with ID and drug dependence are associated with other psychiatric illnesses (42-54%). It is reported that people with intellectual disabilty in Latin America are often institutionalized and hidden from society in poor and overcrowded facilities.

Desempenho cognitivo através do mini-exame do estado mental na distrofia muscular de Duchenne / Cognitive performance by mini mental state examination in Duchenne muscular dystrophy

OBJETIVO: A distrofia muscular de Duchenne (DMD) é frequentemente associada à deficiência intelectual (DI) e ao prejuízo de funções superiores como leitura, raciocínio, lógica, e memória. O objetivo do estudo foi avaliar o desempenho cognitivo de pacientes com DMD através do Mini-Exame do Estado Mental (MEEM), um teste simples e rápido, usado como primeiro rastreio intelectual, principalmente quando baterias psicométricas complexas, dependentes de psicólogos especializados, não estão disponíveis. MÉTODO: Foi realizado um estudo observacional de trinta e quatro meninos com DMD, com idades entre 8 e 22 anos, separados em dois grupos de acordo com a presença de DI moderada-grave, conforme a definição clínica do funcionamento adaptativo do Manual Estatístico e Diagnóstico de Desordens Mentais 5º edição (DSM-5). Foram avaliados a pontuação no MEEM, marcos do desenvolvimento, independência nas atividades de vida cotidiana e capacidade de alfabetização. RESULTADOS: Os marcos motores e de linguagem estavam atrasados (16 meses), e a média no MEEM foi 21, ponto de corte mais baixo do que verificado em pares da mesma idade. O grupo com DI moderada-grave apresentou uma média de 12 no MEEM, e os subtestes de orientação, atenção e cálculo e linguagem foram os que demonstraram piores desempenhos. O ponto de corte de maior acurácia para distinguir DI moderada-grave nos pacientes com DMD foi 21. CONCLUSÃO: O MEEM apresentou adequada sensibilidade (100%) e especificidade (90%) para o ponto de corte de 21, revelando-se um bom método de triagem cognitiva para DI moderada-grave na DMD.

BACKGROUND: Duchenne muscular dystrophy (DMD) is often associated with intellectual disability (ID) and with impairment of higher mental functions as reading, learning, logical thinking and memory. The goal of this study was evaluate the cognitive performance of DMD patients by Mini-Mental State Examination (MMSE), first bedside screening test, widely used in pediatrics, when neuropsychologic batteries, dependent on specialized psychologists, are not easily available in public health system. METHODS: An observational study of thirty-four boys with DMD, aged 8-22 years, was performed, spliting this group into two sub-groups, according to the presence of moderate-severe, defined by Diagnostic and Statistical Manual of Mental Disorders (DSM-5) adaptative functioning clinical criteria. The MMSE scores, developmental milestones, independence in daily life activities and literacy skills were evaluated. RESULTS: Motor and language milestones were reached with 16 months, later than usual and mean on MMSE was 21, lower than in healthy pairs. In assessment by groups, patients with moderate-severe intellectual disability presented a performance in total MMSE (12) and orientation, attention/calculation and language MMSE subtests lower than patients without ID. The most accurate cutoff value on MMSE to distinguish moderate-severe intellectual disability in DMD patients was 21. CONCLUSION: This study has shown adequate sensitivity and specificity of the MMSE for detection of moderate-severe intellectual disability, with almost 100% sensitivity and 90% specificity for cutoff values of 21 points in DMD.

Burden of Mild Mental Retardation attributed to prenatal methylmercury exposure in Amazon: local and regional estimates.

The gold rush in the Amazon Region caused an increase of mercury (Hg) levels in the environment, and, consequently, raised human exposure. Once released into aquatic systems, Hg could generate methylmercury (MeHg), an extremely toxic compound, which is accumulated through trophic chains. Several studies have provided evidences of the brain sensitivity to MeHg, as well as, of the fetus vulnerability during pregnancy. The main objective of this study was to estimate the Mild Mental Retardation (MMR) in Amazonian populations, caused by prenatal exposure to MeHg, using the methodology proposed by Poulin (2008), which quantifies the environmental burden of disease. The estimates of the MMR burden, attributed to prenatal MeHg exposure, were based on the calculation of Disability-Adjusted Life Years (DALY), which were obtained from MMR incidence rate in the studied populations. At the local level, the MMR incidence rate calculations were based on primary data of MeHg exposure of riverine women at childbearing age. The MMR incidence rate was equal to 5.96/1,000 infants, which would result in 2.0 IQ points loss in 34.31% of the newborns. The estimated DALY/1,000 infants was equal to 71.2, while the DALY was 576. For the regional estimates, different exposure scenarios were created. The calculated DALY varied from 3,256 to 65,952 per year.

Intellectual Disability and Psychotic Disorders in Children: Association With Maternal Severe Mental Illness and Exposure to Obstetric Complications in a Whole-Population Cohort.

OBJECTIVE: Children of mothers with severe mental illness are at significantly increased risk of developing intellectual disability. Obstetric complications are also implicated in the risk for intellectual disability. Moreover, children of mothers with severe mental illness are more likely to be exposed to obstetric complications. The purpose of this study was to examine the independent and joint contributions of familial severe mental illness and obstetric complications to the risk of intellectual disability. METHOD: Record linkage across Western Australian whole-population psychiatric, inpatient, birth, and midwives' registers identified 15,351 children born between 1980 and 2001 to mothers with severe mental illness and 449,229 children born to mothers with no mental illness. Multivariable models were adjusted for paternal psychiatric status, parental intellectual disability, and other family and sociodemographic covariates. RESULTS: The risk of intellectual disability was increased among children of mothers with severe mental illness compared with children of unaffected mothers. The impact varied across maternal diagnostic groups. For children of mothers with schizophrenia, the unadjusted odds ratio was 3.8 (95% CI=3.0, 4.9) and remained significant after simultaneous adjustment for exposure to obstetric complications and other covariates (odds ratio=1.7, 95% CI=1.3, 2.3). The odds ratio for exposure to obstetric complications also remained significant after adjustment (odds ratio=1.7, 95% CI=1.6, 1.8). For intellectual disability of a genetic basis, the adjusted odds ratio for maternal schizophrenia was elevated but not statistically significant. Among children with intellectual disability, 4.2% later developed a psychotic disorder, compared with 1.1% of children without intellectual disability. CONCLUSIONS: Maternal severe mental illness and exposure to obstetric complications contribute separately to the risk of intellectual disability, suggesting potentially different causal pathways.

Burden of Mild Mental Retardation attributed to prenatal methylmercury exposure in Amazon: local and regional estimates / Carga de Retardo Mental Leve atribuída à exposição pré-natal ao metilmercúrio na Amazônia: estimativas local e regional

Abstract The gold rush in the Amazon Region caused an increase of mercury (Hg) levels in the environment, and, consequently, raised human exposure. Once released into aquatic systems, Hg could generate methylmercury (MeHg), an extremely toxic compound, which is accumulated through trophic chains. Several studies have provided evidences of the brain sensitivity to MeHg, as well as, of the fetus vulnerability during pregnancy. The main objective of this study was to estimate the Mild Mental Retardation (MMR) in Amazonian populations, caused by prenatal exposure to MeHg, using the methodology proposed by Poulin (2008), which quantifies the environmental burden of disease. The estimates of the MMR burden, attributed to prenatal MeHg exposure, were based on the calculation of Disability-Adjusted Life Years (DALY), which were obtained from MMR incidence rate in the studied populations. At the local level, the MMR incidence rate calculations were based on primary data of MeHg exposure of riverine women at childbearing age. The MMR incidence rate was equal to 5.96/1,000 infants, which would result in 2.0 IQ points loss in 34.31% of the newborns. The estimated DALY/1,000 infants was equal to 71.2, while the DALY was 576. For the regional estimates, different exposure scenarios were created. The calculated DALY varied from 3,256 to 65,952 per year.

Resumo A corrida pelo ouro na Amazônia elevou os níveis de mercúrio (Hg) no ambiente e, consequentemente, aumentou a exposição humana. Uma vez liberado em sistemas aquáticos, o Hg pode gerar metilmercúrio (MeHg), um composto tóxico que se acumula ao longo de cadeias tróficas. Vários estudos têm gerado evidências sobre a sensibilidade do cérebro ao MeHg, bem como sobre a vulnerabilidade do feto durante a gravidez. O principal objetivo deste trabalho foi estimar a carga de Retardo Mental Leve (RML) em populações amazônicas, causada pela exposição pré-natal ao MeHg, utilizando a metodologia proposta por Poulin (2008). As estimativas de RML, atribuída à exposição ao MeHg pré-natal, foram baseadas no cálculo dos Anos de Vida Ajustados por Incapacidade (DALY), que foi desenvolvido a partir de taxa de incidência RML nas populações estudadas. Em nível local, o cálculo da taxa de incidência RML baseou-se em dados primários sobre a exposição ao MeHg em mulheres ribeirinhas em idade fértil. A taxa de incidência RML foi igual a 5,96/1.000 nascidos, o que resulta na perda de 2,0 pontos de QI em 34,31% dos nascidos. A estimativa de DALY/1.000 nascidos foi igual a 71,2, enquanto o DALY foi de 576. Para as estimativas regionais, foram criados diferentes cenários de exposição. Os DALYs calculados variaram de 3.256 a 65.952 por ano.

Metabolic screening and metabolomics analysis in the Intellectual Developmental Disorders Mexico Study.

OBJECTIVE: Inborn errors of metabolism (IEM) are genetic conditions that are sometimes associated with intellectual developmental disorders (IDD). The aim of this study is to contribute to the metabolic characterization of IDD of unknown etiology in Mexico. MATERIALS AND METHODS: Metabolic screening using tandem mass spectrometry and fluorometry will be performed to rule out IEM. In addition, target metabolomic analysis will be done to characterize the metabolomic profile of patients with IDD. CONCLUSION: Identification of new metabolomic profiles associated with IDD of unknown etiology and comorbidities will contribute to the development of novel diagnostic and therapeutic schemes for the prevention and treatment of IDD in Mexico.

Metabolic screening and metabolomics analysis in the Intellectual Developmental Disorders Mexico Study / Tamiz bioquímico y metabolómico en el estudio de los trastornos del desarrollo intelectual en México

Abstract: Objective: Inborn errors of metabolism (IEM) are genetic conditions that are sometimes associated with intellectual developmental disorders (IDD). The aim of this study is to contribute to the metabolic characterization of IDD of unknown etiology in Mexico. Materials and methods: Metabolic screening using tandem mass spectrometry and fluorometry will be performed to rule out IEM. In addition, target metabolomic analysis will be done to characterize the metabolomic profile of patients with IDD. Conclusion: Identification of new metabolomic profiles associated with IDD of unknown etiology and comorbidities will contribute to the development of novel diagnostic and therapeutic schemes for the prevention and treatment of IDD in Mexico.

Resumen: Objetivo: Los errores innatos del metabolismo (EIM) son condiciones genéticas que pueden asociarse con trastornos del desarrollo intelectual (TDI). El objetivo de este estudio es contribuir a la caracterización metabólica de los pacientes con TDI de etiología desconocida. Material y métodos: Se realizará un tamiz metabólico mediante espectrometría de masas-tándem y fluorometría para descartar EIM; además, se analizará el perfil metabolómico de los pacientes con TDI. Conclusión: La identificación de perfiles metabolómicos asociados con los TDI de etiología desconocida contribuirá al desarrollo de nuevos esquemas diagnósticos y terapéuticos para la prevención y tratamiento de los TDI en México.

Preschool Neurodevelopmental Outcomes in Children with Congenital Heart Disease.

OBJECTIVE: To describe preschool neurodevelopmental outcomes of children with complex congenital heart disease (CHD), who were evaluated as part of a longitudinal cardiac neurodevelopmental follow-up program, as recommended by the American Heart Association and the American Academy of Pediatrics, and identify predictors of neurodevelopmental outcomes in these children. STUDY DESIGN: Children with CHD meeting the American Heart Association/American Academy of Pediatrics high-risk criteria for neurodevelopmental delay were evaluated at 4-5 years of age. Testing included standardized neuropsychological measures. Parents completed measures of child functioning. Scores were compared by group (single ventricle [1V]; 2 ventricles [2V]; CHD plus known genetic condition) to test norms and classified as: normal (within 1 SD of mean); at risk (1-2 SD from mean); and impaired (>2 SD from mean). RESULTS: Data on 102 patients were analyzed. Neurodevelopmental scores did not differ based on cardiac anatomy (1V vs 2V); both groups scored lower than norms on fine motor and adaptive behavior skills, but were within 1 SD of norms. Patients with genetic conditions scored significantly worse than 1V and 2V groups and test norms on most measures. CONCLUSIONS: Children with CHD and genetic conditions are at greatest neurodevelopmental risk. Deficits in children with CHD without genetic conditions were mild and may not be detected without formal longitudinal testing. Parents and providers need additional education regarding the importance of developmental follow-up for children with CHD.

Primeras manifestaciones clínicas de un síndrome de X frágil en la comunidad / First clinical manifestations of a case of fragile X syndrome in the community

Fundamento: el síndrome del X frágil es el más común de los trastornos de retraso mental ligados al cromosoma X.Objetivo: presentar las primeras manifestaciones clínicas de un caso de síndrome de X frágil que no comenzó con retardo del desarrollo psicomotor.Caso clínico: paciente que es remitido a consulta de genética por presentar macrocráneo y orejas displásicas en forma de copa. Al año y seis meses presentó retardo del desarrollo psicomotor. El examen físico, los exámenes complementarios dieron el diagnóstico de un síndrome del X Frágil. Se le puso tratamiento en consulta de estimulación temprana y el paciente mejoró el desarrollo psicomotor.Conclusiones: la aparición de macrocefalia y el retardo del desarrollo psicomotor contribuyeron a realizar el diagnóstico oportuno de esta enfermedad. La estimulación temprana permitió avances en el desarrollo psicomotor del paciente(AU)

Background: fragile X Syndrome is the most common mental retardations disorders linked to X chromosome.Objective: to show the first clinical manifestations of a case of Fragile X Syndrome case that did not began with psychomotor development retardation.Clinical case: a patient who is transferred to genetic consult for presenting macrocranium, dysplastic ears in form of cup. Aged one year and six month old, he had psychomotor development retardation. Physical examinations and complementary test confirmed Fragile X Syndrome diagnosis. The patient was treated in early stimulation consult which improved the psychomotor development retardation.Conclusions: the presence of macrocephaly and later psychomotor development retardation helped to make the appropriate diagnosis of that disorder. Early stimulation permitted advances in psychomotor development in this patient(AU)

Intellectual Disability in a Birth Cohort: Prevalence, Etiology, and Determinants at the Age of 4 Years.

BACKGROUND: Intellectual disability (ID), characterized by impairments in intellectual function and adaptive behavior, affects 1-3% of the population. Many studies investigated its etiology, but few are cohort studies in middle-income countries. AIMS: To estimate prevalence, etiology, and factors related to ID among children prospectively followed since birth in a Southern Brazilian city (Pelotas). METHODS: In 2004, maternity hospitals were visited daily and births were identified. Live-born infants (n = 4,231) whose family lived in the urban area have been followed for several years. At the age of 2 and 4 years, performances in development and intelligence tests were evaluated using the Battelle Developmental Inventory and Wechsler Intelligence Scale, respectively. Children considered as having developmental delay were invited to attend a genetic evaluation. RESULTS: At 4 years of age, the prevalence of ID was 4.5%, and the etiology was classified into 5 groups: environmental (44.4%), genetic (20.5%), idiopathic (12.6%), neonatal sequelae (13.2%), other diseases (9.3%). Most children presented impairment in two or more areas of adaptive behavior. There was no difference in prenatal care attendance or maternal schooling among the groups. CONCLUSION: For about 40% of children, ID was attributed to nonbiological factors, suggesting that the rate may be reduced with appropriate interventions early in life.

Initial Description of the Presumed Congenital Zika Syndrome.

OBJECTIVES: To provide an initial description of the congenital syndrome presumably associated with infection by Zika virus compared with other syndromes including congenital infections of established etiologies. METHODS: We provide an overview of a published case series of 35 cases, a clinical series of 104 cases, and published and unpublished reports of clinical and laboratory findings describing cases diagnosed since the beginning of the epidemic of microcephaly in Brazil. RESULTS: About 60% to 70% of mothers report rash during pregnancy; mainly in the first trimester. Principal features are microcephaly, facial disproportionality, cutis girata, hypertonia/spasticity, hyperreflexia, and irritability; abnormal neuroimages include calcifications, ventriculomegaly, and lissencephaly. Hearing and visual abnormalities may be present. CONCLUSIONS: Preliminary data suggest that severe congenital abnormalities are linked to Zika virus infection. Cases have severe abnormalities, and although sharing many characteristics with congenital abnormalities associated with other viral infections, abnormalities presumably linked to the Zika virus may have distinguishing characteristics. These severe neurologic abnormalities may result in marked mental retardation and motor disabilities for many surviving offspring. POLICY IMPLICATIONS: Affected nations need to prepare to provide complex and costly multidisciplinary care that children diagnosed with this new congenital syndrome will require.