The management of children with spinal dysraphism

Altered activity of mPFC pyramidal neurons and parvalbumin-expressing interneurons during social interactions in a Mecp2 mouse model for Rett syndrome

Social memory impairments in Mecp2 knockout (KO) mice result from altered neuronal activity in the monosynaptic projection from the ventral hippocampus (vHIP) to the medial prefrontal cortex (mPFC). The hippocampal network is hyperactive in this model for Rett syndrome, and such atypically heightened neuronal activity propagates to the mPFC through this monosynaptic projection, resulting in altered mPFC network activity and social memory deficits. However, the underlying mechanism of cellular dysfunction within this projection between vHIP pyramidal neurons (PYR) and mPFC PYRs and parvalbumin interneurons (PV-IN) resulting in social memory impairments in Mecp2 KO mice has yet to be elucidated. We confirmed social memory (but not sociability ) deficits in Mecp2 KO mice using a new 4-chamber social memory arena, designed to minimize the impact of the tethering to optical fibers required for simultaneous in vivo fiber photometry of Ca 2+ -sensor signals during social interactions. mPFC PYRs of wildtype (WT) mice showed increases in Ca 2+ signal amplitude during explorations of a novel toy mouse and interactions with both familiar and novel mice, while PYRs of Mecp2 KO mice showed smaller Ca 2+ signals during interactions only with live mice. On the other hand, mPFC PV-INs of Mecp2 KO mice showed larger Ca 2+ signals during interactions with a familiar cage-mate compared to those signals in PYRs, a difference absent in the WT mice. These observations suggest atypically heightened inhibition and impaired excitation in the mPFC network of Mecp2 KO mice during social interactions, potentially driving their deficit in social memory.

Prevalence of spina bifida among children and adolescents in metropolitan Atlanta

BACKGROUND

Although studies have examined the prevalence of spina bifida (SB) among births, little is known about the SB prevalence among children and adolescents. We estimated the prevalence of SB among children and adolescents in metropolitan Atlanta.

METHODS

This study used data from a population-based registry of birth defects, with information on children with SB (cases) born in five Atlanta counties from 1979-2002. The population at risk was derived from United States Census data and variations in SB prevalence were examined by race/ethnicity, sex, lesion level, age group under 20 years, 4-year birth cohort, and time period using Poisson regression.

RESULTS

From 1979 to 2002, SB birth prevalence decreased from 6.3 to 3.2 per 10,000 live births (p < 0.001) and SB prevalence within each age group also declined. In 2002, there were 211 children 0-19 years old surviving with SB in Atlanta (2.4 per 10,000 children 0-19 years old); prevalence of SB was higher among non-Hispanic whites and among children with lumbosacral lesion but did not vary by sex. With the exception of the most recent birth cohort (1998-2002), within each 4-year birth cohort, the prevalence of SB was generally higher among non-Hispanic whites than among non-Hispanic blacks.

CONCLUSIONS

This study provides minimum prevalence estimates among children and adolescents with SB in metropolitan Atlanta, and identifies race/ethnic disparities in such prevalence estimates. This information could be useful for assessing the specialized health care needs for children with SB and the possible reasons for the racial/ethnic variation in prevalence of SB.

Prevalence of down syndrome among children and adolescents in metropolitan Atlanta

BACKGROUND

Down syndrome (DS) prevalence estimates beyond infancy are needed to assess health service needs among those with DS.

METHODS

Children with DS born in metropolitan Atlanta from 1979 through 2003 were ascertained from a population-based birth defects registry. Vital status through 2003 was obtained using case records, vital records, and the National Death Index. Prevalence was calculated by dividing the children surviving with DS by the population derived from U.S. Census estimates. Variations in DS prevalence by race, heart defects, age, birth cohort, and time period were examined using Poisson regression.

RESULTS

In metropolitan Atlanta in 2003, there were 67 livebirths with DS (13.0 per 10,000 livebirths) and 738 0- to 19-year-olds surviving with DS (8.3 per 10,000 population). Over time, births to mothers 35 years and older and DS birth prevalence increased. Birth prevalence was higher among Whites, did not vary by sex, and was higher for infants without heart defects. DS prevalence among 0- to 14-year-olds increased over time (p < .05). Within each 5 year birth cohort, prevalence decreased with age: this decrease was greater among Blacks than among Whites and among children with heart defects than among children without heart defects.

CONCLUSIONS

DS prevalence increased among livebirths and among young children. Further studies are warranted to determine whether health services are meeting the needs of an increasing number of children with DS.

Pre-school follow-up of a cohort of children with myelomeningocele in Cape Town, South Africa

A cohort of South African children with myelomeningocele was followed for 5 years. Fifty-three were from metropolitan Cape Town and 65 from rural areas including the tribal region of Transkei. The mean general developmental quotient (GQ) at 5 years of age was lower than that previously reported. Black and coloured children had lower GQs than white children, but there were no significant differences between those from the urban and the rural areas. Early closure of the lesion and delivery by caesarean section were associated with higher levels of general developmental functioning. Central nervous system infections and the placement of more than one shunt for hydrocephalus resulted in lower GQs. Lesions above L2 were associated with non-ambulation. Ambulation was more likely in children in Cape Town than in rural children. Urinary incontinence occurred more frequently in rural children and among those in lower socio-economic circumstances.

Adult stature and anthropomorphic measurements of patients with myelomeningocele

Children with myelomeningocele are extremely short, yet little data exists on adult stature and anthropomorphic measurements. We measured the recumbent length, weight, arm length, sitting height and calculated body mass index of 54 adults with myelomeningocele. Mid parental height was also calculated. Measurements were compared with normative data. Patient charts were reviewed for history of hydrocephalus. The 27 males and 27 females had a mean age of 24.8 +/- 5.7 years. The mean length for adult females was 141.9 +/- 12 cm and was 152.1 +/- 13 cm for males. Patients with thoracic level of lesions were shorter than those with lumbar level who were, in turn, shorter than those with sacral levels. Recumbent length, sitting height, arm length and arm span were significantly smaller than expected values. Recumbent length was smaller than mid parental height. Those with ventriculoperitoneal shunts, required for hydrocephalus, were shorter than these without a shunt.

CONCLUSION

Adults with myelomeningocele have significant short stature. Arm span is not an interchangeable measure with length for patients with myelomeningocele. Multiple factors are likely to be responsible for the observed short stature.

Helping families with children with developmental disabilities

The physician can help the child with developmental disabilities maximize his or her potential and minimize the adverse effects on the family by understanding the emotional and other impacts of a developmental disability; providing information about diagnosis, prognosis, and associated problems; providing nonjudgmental listening; providing information about community resources, including parent-support groups; ensuring adequate communication with everyone involved in the care of the child; and referring the family to appropriate agencies and providers.

Rehabilitation for developmental disabilities

This article describes the role of physical and occupational therapists in the rehabilitation of children with a variety of developmental disabilities. Emphasis has been placed on alerting the pediatrician to the types of assessment and treatments provided in order to encourage early referral of clients.

Assessment of obesity of children with spina bifida

Percentage body fat of 35 children with spina bifida and 129 age-matched normal children was measured by underwater weighing and skinfold thickness to assess obesity. Percentage body fat of patients below five years was similar to that of controls; however, 58 per cent of patients above six years had an increased percentage of body fat. The neurological level and ambulatory ability were associated with percentage body fat. A significant correlation between percentage body fat and hydrocephalus suggests that the metabolic and nutritional maladaptation is caused not only by these patients' physical inactivity but also by the condition itself. Appropriate nutritional and mobility programmes should be started early to prevent the development of obesity.

The Rett and Rett-like syndromes: a broad concept

Eight patients who satisfied the following three criteria: 1) autistic behavior, 2) mental retardation and 3) stereotypic hand movements were evaluated. Four patients fulfilled the diagnostic criteria for the Rett syndrome developed by representatives of the International Rett Syndrome Association and the Center for Disease Control, Atlanta, USA. The other four Rett-like patients were atypical in the sense that the manifestations were incomplete or psychomotor development throughout the first 6 months of life was abnormal or the disease was heralded by infantile spasms with transient stereotypic hand movements or the baby was born with congenital microcephaly. All eight patients were girls. No laboratory test result specific for the Rett syndrome or Rett-like syndrome was obtained.

Cognitive and motor abilities in preschool hydrocephalics

The neuropsychological performance of three groups of preschool children was evaluated: (a) one with hydrocephalus associated with myelomeningocele; (b) one with hydrocephalus associated with intraventricular hemorrhage and very low birth weight; and (c) a nonhydrocephalic normal comparison group. Multivariate profile analysis revealed lower levels of performance on measures of verbal and nonverbal cognitive skills for both groups of hydrocephalic children relative to normals. Comparison of group profiles on tasks requiring figure copying as opposed to figure matching and analysis of specific gross and fine motor skills revealed that both hydrocephalic groups had impaired visual-motor integration in the presence of average visual perceptual matching. In addition, different patterns of motor skill deficits were found for each hydrocephalic group. The results of this study suggest that decreased visual-motor integration and etiology-specific motor deficits are major sequelae of these forms of hydrocephalus in the preschool years.