Phenotypic variance in children with chromosomal aberrations – A cohort study

Abstract

Background: Chromosomal abnormalities are the result of alterations in the number or structure of chromosomes leading to significant human morbidity and mortality. They are responsible for large proportion of miscarriages, developmental delay, disorders of sexual development, congenital malformations, and mental retardation. Objectives: The objectives of the study were to find the occurrence of chromosomal abnormalities in infants and children with various phenotypic presentations and to analyze the impact of associated risk factors for chromosomal abnormalities in children. Materials and Methods: A retrospective single-center study, based on the outcome data of chromosomal analysis of 112 children admitted to the pediatric department of our hospital over a period of 3 years, was reported. The data were collected from the electronic medical records for analysis, including maternal age, consanguinity, family history of any congenital anomalies and malformations, clinical details, and the results of chromosomal analysis. Results: A statistically significant association between the presence of dysmorphic features and chromosomal abnormalities with 3 times increased risk when compared to children with no dysmorphism (relative risk [RR] 3.06, 95% confidence interval [CI] 1.71–5.50, p=0.0002). Among the congenital anomalies, the presence of congenital heart defects had strong association and was found to be 43% higher in children with chromosomal abnormalities (RR 1.43, 95% CI 1.10–1.86, p=0.0069). Our study demonstrated a strong association for maternal age >35 years and the risk for chromosomal abnormality. It was 1.75 times more than the children born to mothers ?35 years age (RR 1.75, 95% CI 1.29–2.36, p=0.0003). Conclusion: Cytogenetics has a major role in diagnosis of chromosomal abnormalities, especially in children with dysmorphic features and congenital heart defects. The early diagnosis is important for planning and resource allocation of specialized health services directed toward the families and infants.