Growth and Cytogenetic Profile and Vitamin D levels in children with Down Syndrome

INTRODUCTION: Down syndrome is the most frequent genetic cause of mild to moderate mental retardation and associated medical problems and occurs in 1 out of 800 live births, in all races and economic groups. Down syndrome is named after John Langdon Down, the first physician to identify the syndrome in 1866. In 1959 Lejeune, Gautier and Turpins determined that Down syndrome was caused by trisomy 21. Down syndrome and chromosomal nondysjunction occur more often in the offspring of mothers conceiving at an older age. Today with the focus on education, employment, career and the need to be financially stable before having children, late child birth is becoming the norm. Hence the incidence of Down syndrome is likely to increase. The survival of children with Down syndrome has increased. More parents are now seeking care for these children. Hence it is imperative that we anticipate an increase in incidence of children with Down syndrome and their presence at our clinics. Improving their quality of life and helping them to reach their maximum potential should be our goal. Children with Down syndrome are shorter than their peers. Average height at most ages is around the 2nd centile for the general population. For the majority the cause of growth retardation is not known. Some conditions leading to poor growth (congenital heart disease, sleep related upper airway obstruction, coeliac disease, thyroid hormone deficiency, deficiency of insulin like growth factor 1 and nutritional inadequacy caused by feeding problems) occur more frequently among those with the syndrome. Adults with Down syndrome are prone for osteoporosis. Vitamin D deficiency is known to result in both deficient growth and osteoporosis. There is very little data on Vitamin D levels in children with Down syndrome and the effect it had on growth. We wanted to see if these children had reduced Vitamin D levels and consequently delayed growth as correction of Vitamin D deficiency is relatively easy. Surprisingly, only one study in the world has looked at the Vitamin D status in children with Down syndrome. That was done on a group of 21 children in Spain, 16 years ago, which did not show any low levels of Vitamin D metabolites in any of these children. Hence there was definitely scope for research in this area, before any final conclusion could be made. AIM OF THE STUDY: The main aims of the study were: 1. To study the prevalence of Vitamin D deficiency by assessing 25(OH) Vitamin D levels in children with Down syndrome. 2. To assess the effect of 25(OH) Vitamin D deficiency on height, bone age and other biochemical markers in these children. Since there were very few recent clinical studies published on children with Down syndrome in India, we also aimed to look at 1. Assessment of the phenotypic and cytogenetic profile of Children with Down syndrome and presence of common associated malformations, deficiencies and associated illnesses. 2. An evaluation of their social quotient. MATERIALS AND METHODS: Study setting: The study was conducted in the Department of Child Health, Christian Medical College, Vellore – a tertiary care medical centre in South India. Study Period: The duration of the study was from October 2007 to September 2008. Study Design: Prospective descriptive study. Instuments: Questionnaire. Inclusion Criteria: Children clinically suspected to have Down syndrome between the ages of 5 months- 16 years and who were cytogenetically proven were enrolled in the study. • Informed consent was obtained from the parents. • Relevant history and detailed clinical examination was carried out. • Measurements were taken by the Primary investigator or trained nurses. Height was measured on the infantometer in those less than 2 years or those who could not stand. In older children the stadiometer was used. Weight was checked on a sensitive electronic weighing scale to the closest 10 grams. The head circumference was measured using non stretchable tapes to the nearest millimeter taking the maximum occipitofrontal diameter. • The height and weight (and head circumference for children less than 3 years) were plotted on 2 growth charts – growth charts of “normal” Indian children (Agarwal) as recommended by the Expert group of the Indian Academy of Pediatricians 36 and growth charts for children with Down syndrome as described by Cronk. • Blood was collected for the following investigations: complete blood count, thyroid function test and thyroid stimulating hormone, calcium, phosphorus, alkaline phosphatase, 25(OH) Vitamin D levels (by Automated Chemiluminescent Immunoassay) and karyotyping (Annexure 1) • X-ray left hand and wrist was taken for bone age and lateral neck X-ray in neutral position to look for atlanto-axial dislocation in children older than 3 years. Echocardiogram, eye checkup and hearing assessment were done. Developmental assessment (social quotient) was done using the Vineland Social Maturity Scale. • The data was entered in a spreadsheet and analyzed by SPSS software version 11. SUMMARY: A prospective descriptive study was conducted in the Department of Child Health, Christian Medical College, Vellore – a tertiary care medical centre in South India from October 2007 to September 2008. The aims were to: 1.. Study the prevalence of Vitamin D deficiency by assessing 25(OH) Vitamin D levels in children with Down syndrome. 2.. Assess the effect of Vitamin D deficiency on height, bone age and other biochemical markers in these children. 3. Assessment of the phenotypic and cytogenetic profile of children with Down syndrome and presence of common associated malformations, deficiencies and associated illnesses. 4. An evaluation of their social quotient. a. 56 cytogenetically proven Down syndrome were enrolled in the study. b. Frequency of regular trisomy was 89.3%, translocation was 7.1% and mosaicism was 3.6%. c. Prevalence of 25(OH)vitamin D deficiency using a cut off value of 10ng/ml was 26.8% d. There was no significant effect of vitamin D deficiency on height, bone age or other associated biochemical markers e. The prevalence of phenotypic features was as follows: hypertelorism (3.6%), epicanthal folds (64.3%), upslanting eyes (98.2%), malformed ears (26.8%), flat facies (96.4%), simian crease (50%), clinodactyly (69.6%) and sandal gap (50%). Prevalence of Mild TSH elevation 16%, Hypothyroidism 7%, Hyperthyroidism 4%, Ophthalmologic abnormalities were detected in 46% and ENT related abnormalities in 53%. Pre B Acute lymphoblastic leukaemia was identified in 5.4% of the children. Cardiac anomalies were detected in 42%. The common cardiac abnormalities were atrial septal defect, ventricular septal defect and patent ductus arteriosus. 12% (3/25) had evidence of atlanto-axial dislocation. 64% of children had social quotient <70. CONCLUSIONS: 1.The prevalence of 25(OH) Vitamin D deficiency in children with Down syndrome was 26.8%. 2. There was no significant effect of 25(OH) Vitamin D deficiency in the height, bone age and other biochemical markers in these children

Objective Analysis of Marker Bias in Higher Education

Marker bias has been a serious factor contributing to discrepancy in assessments. In this study we analyze one year students' results in a Business Faculty within an Australian university to understand the extent of variation induced by marker bias in multiple marker scenarios. The study shows interesting insights regarding the marking trends of a particular marker, and shows variations among markers in a particular course. The study paves the way for quantification of marker variation through objective analysis

Aches and Pains with a Shocking Rash

Peer Reviewe

Impact of pre-hospital care on the outcome of children arriving with agonal breathing to a pediatric emergency service in South India

Background: Data on the prehospital interventions received by critically ill children at arrival to Paediatric Emergency Services (PES) is limited in developing countries. This study aims to describe the pre-hospital care scenario, transport and their impact on outcome in non-traumatic, acutely ill children presenting in PES with agonal breathing. Methods: Prospective observational study done on children aged below 15 years arriving in PES with agonal breathing due to non-trauma related causes. Results: Out of 75 children studied, 69% were infants. The duration of illness among 65% of them (75) was less than 3 days. Majority of them (81%) had received treatment prior to arrival. Government sector physicians (72%), half of them (51%) being pediatricians were the major treating doctors. 37% of the children had arrived to the Emergency in an ambulance. Cardiopulmonary Resuscitation (CPR) was given to 27% on arrival in PES. Other interventions included fluid boluses to correct shock (92%) and inotrope infusion (56%). Sepsis (24%) and pneumonia (24%) were the most common diagnoses. Out of 75, 57 (76%) children who were stabilized and shifted to PICU and among them 27 (47%) survived to discharge. Normal blood pressure (p=0.0410) and non-requirement of CPR (0.0047) and inotropic infusion (0.0459) in PES were associated with a higher chance of survival. Conclusion: 36% (27/75) of children who arrived to our PES with agonal breathing survived to hospital discharge. Survival was significantly better among those who did not need CPR

Objective analysis of marker bias in higher education

Marker bias has been a serious factor contributing to discrepancy in assessments. In this study we analyze one year students' results in a Business Faculty within an Australian university to understand the extent of variation induced by marker bias in multiple marker scenarios. The study shows interesting insights regarding the marking trends of a particular marker, and shows variations among markers in a particular course. The study paves the way for quantification of marker variation through objective analysis