Cognitive performance in Rett syndrome girls: a pilot study using eyetracking technology.

BACKGROUND: Rett syndrome (RS) is a pervasive developmental disorder with cognitive and neuromotor impairments (including loss of handiness and loss of communicative skills). OBJECTIVE: To verify whether girls with RS use their gaze intentionally, by observing their performance in three cognitive tasks: (1) verbal instruction condition (look at picture X), (2) recognition and matching of pictures (look at the one that is the same), and (3) categorization of pictures (look at the one that is similar). METHOD: Seven girls diagnosed with RS according to DSM-IV criteria were studied. Eyegaze technology was used to record the girls' eye movements' responses to visual stimulation. RESULTS: The comparison of fixation time on the alternatives revealed a higher percentage (62.4%) of correct alternatives (chi(2) = 76.31; P = 0.000). Of the seven children assessed, only one did not present predominance of fixations on the correct alternatives in any one of the tasks. One did well in all tasks. Six responded correctly to all verbal instructions. CONCLUSION: The rate of correct answers suggests that there is measurable and intentional gaze in RS girls and it can be used as a path to explore their cognitive performance.

Rett syndrome in a boy with a 47,XXY karyotype confirmed by a rare mutation in the MECP2 gene.

Rett syndrome (RTT) is an X-linked condition which affects almost exclusively females. Here we report the first case of RTT syndrome in a boy with an XXY chromosomal constitution. Mutation analysis of the MECP2 gene in the affected patient revealed a 423 C-->G substitution in exon 4, resulting in a new stop codon (Y141 X). This change was not present in both his parents or in his older sister. Taking into account the incidence of both RTT syndrome as well as of Klinefelter syndrome, the probability for the simultaneous occurrence of these two events is very low (about approximately 1 in 10 to 15,000,000 births). However, the recent identification of mutations in the MECP2 gene in affected males indicates that screening of the MECP2 gene should be considered also in males with severe mental retardation (MR) in whom the most common forms of MR have been excluded.

[Rett phenotype in patient with XXY karyotype: case report]. / Fenótipo Rett em paciente com cariótipo XXY. Relato de caso.

We report the case of a XXY boy who presents progressive neurological disorder which has started around eleven months of age, with developmental stagnation followed by regression. The child presents as well stereotypic hand movements, loss of purposeful hands use and microcephalia. Presence of any defined systemic or neurological condition which could be pointed out as the possible etiological factor for the case was not found out by investigations. It deals with a boy with phenotypic alterations very similar to those considered typical for Rett syndrome which associated with chromosomal alteration (XYY karotype) constitute evident scientific interest.

Deficiency of merosin (laminin M or alpha 2) in congenital muscular dystrophy associated with cerebral white matter alterations.

Recently, a deficiency of merosin has been reported in patients with classical congenital muscular dystrophy (CMD), while other patients, with indistinguishable clinico-pathological features, do not present this deficiency, suggesting genetic heterogeneity. The purpose of the present investigation was to assess merosin distribution and quantity in 21 clinically well characterized Brazilian CMD patients, in order to: a) estimate the proportion of merosin-deficient cases in this group of patients; b) characterize phenotypically merosin-negative, as compared to merosin-positive patients. Merosin deficiency was found in 11 patients and all the seven who had been submitted to neuroimaging studies showed evidence of periventricular dysmyelination. A normal pattern of 43 DAG was found in all patients, which suggest that this protein is not preferentially involved in a third form of merosin-positive CMD. Results from the present study are further suggestive, but do not prove, that the association of merosin deficiency with white matter alterations represents a genetic entity with common clinical, laboratory and neuroimaging findings.

Ataxia-telangiectasia: a clinical and laboratory review study of 14 cases.

Fourteen patients with ataxia-telangiectasia and 10 relatives were studied. Besides neurological examination, laboratorial investigations as to their immunological condition were carried out. In this study, our attention was attracted to the most frequent and relevant laboratorial data being decreased serum and salivary levels of IgA, decreased rate of blastic transformation of lymphocytes and increased serum levels of alpha-fetoprotein (AFP). On the other hand, no patient showed increased levels of carcinoembryonic antigen (CEA). Our population reported a consanguinity rate of 28.5%.

[Neurocutaneous melanosis. Report of a case]. / Melanose neuro-cutânea. Relato de um caso.

The clinical, laboratorial and radiological features of a 3-month-old child with neurocutaneous melanosis are described. The patient was born with multiple disseminated benign cutaneous nevi, proven by skin-biopsy, and presented with drug-resistant seizures and psycho-motor retardation. Serial cerebrospinal fluid studies showed high protein and low glucose levels, with pleocytosis and malignant cells in the fluid. Pneumoencephalogram showed mild non-obstructive hydrocephalus. Immunological studies showed normal immunological activity at three months of age and very poor activity at one year. The patient died at 16 months of age, after the sudden onset of intracranial hypertension and meningeal signs. Immunotherapy and chemotherapy were suggested but not accepted by the family. Some comments are made based on this and other 43 cases described in the literature; the value of laboratory studies in detecting malignant transformaiton in the meninges in patients with benign skin nevi is stressed.

Teste de Bender, teste Metropolitano de Prontidão e E. E. G: suas relações em um grupo de crianças de 6 a 8 anos de idade / Bender test, metropolitan achievement test and E. E. G: their relations in a six and eight years old children group

Os autores estudaram os resultados do teste de Bender, do eletroencefalograma e do teste Metropolitano de Prontidão em um grupo de 44 crianças de 6 a 8 anos de idade. Não foi encontrada qualquer correspondência entre os resultados eletroencefalográficos e os do teste de Bender sob qualquer um de seus aspectos de avaliação segundo KOPPITZ no diagnóstico de lesão cerebral, verificação esta considerada de valor, por ser o teste de Bender constantemente utilizado com a finalidade de diagnosticar lesão cerebral em nosso meio. Por outro lado, encontrou-se uma associação vidente entre os resultados obtidos no teste de Bender e no teste Metropolitano de Prontidão, resultado que está de acordo com a maioria dos autores que os estudaram. Chamou a atenção dos autores a alta incidência de lesão cerebral diagnosticada pelo eletroencéfalograma nas crianças estudadas, distribuidas de maneira equitativa nos dois grupos extremos classificados pelo teste Metropolitano de Prontidão, concluindo pela ausência de relação entre alterações eletoencefalográficas e aparecimento de dificuldades na alfabetização. (AU)