Developmental correlates of school-age children with a history of benign congenital hypotonia

Screening in child health: studies of the efficacy and relevance of preventive care practices

BACKGROUND

Pediatric screening enables the prevention or early detection of diseases and developmental disturbances in infancy and childhood. Screening is a standard component of pediatric practice in many countries, but its scientific basis is not well known.

METHODS

The scientific justification for pediatric screening beyond the neonatal period is presented on the basis of a selective review of the literature on some aspects of pediatric screening.

RESULTS

The level of evidence varies highly among pediatric screening interventions and can be difficult to determine because of confounding variables. Parent counseling is associated with improvements in child-raising competence, accident prevention, and reading behavior. The early detection of abnormalities in a child's motor, linguistic, mental, or social development is possible and often leads to effective early interventions. Cyanotic congenital heart defects can be detected with 63% sensitivity and 99.8% specificity; cerebral palsy can be diagnosed with 33% to 100% sensitivity and 52.3% to 100% specificity (different figures from multiple studies). Physical therapy seems to improve some manifestations of cerebral palsy. Motor development at 90 days is correlated with motor development at 57 months (72% sensitivity, 91% specificity). A developmental quotient above 85 in a two-year-old child is correlated with an intelligence quotient above 85 when the child is 7 years old.

CONCLUSION

There is an increasing amount of scientific evidence in favor of pediatric screening. Nonetheless, further epidemiological studies are needed.

Does physical therapy improve outcome in infants with joint hypermobility and benign hypotonia?

This study examined the effect of the frequency of physical therapy on the outcome of infants referred for delayed motor development due to joint hypermobility and benign hypotonia. The study groups comprised 29 infants (8-12 months) who were randomly placed into a monthly and weekly treatment groups. No difference was found between the 2 study group scores on the different tests at all assessment points. However, assessment of walking at the age of 15 months revealed a clear advantage of the infants who were treated weekly. Our study demonstrated a minor benefit of weekly treatment protocol only in the achievement of independent walking in children with joint hypermobility and benign hypotonia. It did not prove an advantage of weekly physical therapy. It seems that monthly physical therapy combined with a home treatment protocol implemented by the primary caregivers is sufficient to achieve motor catch-up.

Outcomes of infants with idiopathic hypotonia

PURPOSE

To describe the outcomes of children diagnosed before the age of two with idiopathic hypotonia.

METHODS

A total of 105 parents of children who were diagnosed with hypotonia returned a questionnaire. Medical records were reviewed.

RESULTS

A transient impairment group (10.5%) reported no problems. A minimal impairment group (32.4%) had mild problems such as learning disability or language delay but no major developmental diagnosis. A globally impaired group (40.9%) had mental retardation or a recognizable genetic/developmental diagnosis. More than 50% of the minimal impairment group had poor coordination, language delay, and learning difficulties. The mean walking age (minimal group) was 22 months. Initial fine motor and cognitive, but not gross motor, developmental quotients were significantly greater in the minimal compared with global impairment group.

CONCLUSION

Deficits in motor coordination, language, and learning difficulties were common problems that persisted in the minimal and global impairment groups.

Developmental evaluation of children born to mothers occupationally exposed to waste anesthetic gases

BACKGROUND

The etiology of developmental delay in children is frequently unknown. Increasing evidence supports the possibility that environmental and occupational factors might be part of the basis for such delays. This study focuses on the development of children born to mothers who were exposed during their pregnancy to waste anesthetic gases.

METHODS

The study population included 40 children aged 5-13 years born to female anesthesiologists and nurses working in operating rooms (OpRs) exposed to waste anesthetic gases, and 40 unexposed children born to female nurses and physicians who worked in hospitals during their pregnancy but did not work in OpRs. The unexposed group was matched for children's age and gender and maternal occupation (nurses vs. doctors). By means of standardized developmental tests, the present study population was evaluated for their medical and neurodevelopmental state. Questionnaires were given for the detection of attention and activity levels as perceived by the parents. Additional questionnaires dealt with information concerning developmental milestones, maternal and fetal morbidity, and gynecological history.

RESULTS

No differences were noted between the groups as newborns or in developmental milestones at the age of 5-13 years; however, the mean score of gross motor ability was significantly lower in the exposed versus the unexposed group. Additionally, the mean score of the DSM-III-R Parent-Teacher Questionnaire (PTQ) (i.e., measure of inattention/hyperactivity) was higher in the exposed group. The level of exposure, as measured by the number of weekly hours in the OpRs, was significantly and negatively correlated with fine motor ability and the score of IQ performance.

CONCLUSIONS

Our study supports the hypothesis that occupational exposure to anesthetic gases might be a risk factor for minor neurological deficits of children born to mothers who work in OpRs and therefore indicates the need for more studies in this area and perhaps more caution among OpR pregnant women and employers.

Congenital hypotonia with favorable outcome

Congenital hypotonia with favorable outcome is characterized by an early neonatal onset and a benign clinical course. The old term, proposed by Walton, was benign congenital hypotonia, denoting the presence of muscle weakness and hypotonia, with the exception of Werdnig-Hoffmann disease. It has been clear that this term includes congenital myopathies with definite changes in the muscle fiber. However, many cases remain unclarified. The term congenital hypotonia with favorable outcome includes only these last cases. A long-term follow-up study of children with congenital hypotonia with favorable outcome is presented, and a hypothetical mechanism underlying muscle shortening is discussed. The study was carried out at the Department of Child Neuropsychiatric Sciences, University "La Sapienza" of Rome, during the period 1985-2000, and included 41 patients with congenital hypotonia. Our study confirms the good prognosis of congenital hypotonia with favorable outcome and suggests a correlation with joint hyperlaxity, which is observed in many parents of our children, as if the latter developed from the former. On the basis of experimental changes occurring in the muscles, we believe that in our cohort the main cause of shortening is caused by an increase in joint mobility, which keeps muscles shortened in both the passive and active states for a long time. If this view is confirmed by other studies, we suggest continuous muscle exercise as a preventive treatment.