Cardiac spectrum, cytogenetic analysis and thyroid profile of 418 children with Down syndrome from South India: A cross-sectional study

Objective: To describe the spectrum of congenital heart disease in children with Down syndrome and their cytogenetic profile (and that of parents of those with translocation), and thyroid profile. Methods: A cross sectional study was conducted in 418 consecutive patients with Down syndrome attending the Department of Pediatric Genetics from a tertiary care centre in Kerala with a comprehensive Pediatric Cardiac Program, from November 2005 through April 2012. All children were offered cytogenetic analysis and were subjected to echocardiography. Parental karyotyping was offered for children with translocation type of Down syndrome. The thyroid profiles of all children were checked at the first visit and once every 6 mo during follow up. Results: Congenital heart disease was present in 256 (63.4 %) of 404 children with Down syndrome. Ventricular septal defect (72; 28.1 %) was the commonest, followed by atrio-ventricular septal defect (70; 27.3 %) and patent ductus arteriosus (43; 16.8 %). Surgical correction was accomplished in 104 (40.6 %) with excellent intermediate-term outcomes. Three hundred eighty seven of 418 children (92.6 %) underwent cytogenetic tests. The abnormalities included non-disjunction (340, 87.8 %), translocation (33, 8.5 %) and mosaicism (12, 3.1 %). Hypothyroidism was detected in 57 children (13.6 %). Conclusions: The prevalence of congenital heart disease in children with Down syndrome in Kerala is the highest reported (63.4 %). Ventricular septal defect is the most common heart disease in the present study. The results highlight the changing attitudes of families towards the surgical correction of congenital heart disease in children with Down syndrome. Prevalence of hypothyroidism in Down syndrome in Kerala is 13.6 %.