Background: Down syndrome (DS) is the most common chromosomal disorder in the world. The condition includes typical facial dysmorphism with intellectual disability and diverse associated visceral anomalies. DS is often diagnosed in Congo Brazzaville, but there are only a few significant reports of the condition. This preliminary study aimed to determine the prevalence and the pattern of DS associated anomalies in Congolese children.
Patients and methods: This work included patients with Down’s syndrome (DS) provided from a congenital malformation series seen at the pediatric services (Neonatology and Intensive care) in University Teaching Hospital (UH) of Brazzaville for a period of five years (from January 2011 to January 2016). Some of the patients were newborns and some were older children.
It was a retrospective study based on the pediatric registries and records. The diagnosis of DS was based on clinical features. Systematic chest radiography was performed in cases of any associated anomalies and two-dimensional echocardiography with doppler in cases of cardiac defects. The scanner examination was made in cases of cerebral anomalies.
Results: During the study period, a total of 430 children with congenital malformations have been seen, from which 19.3% (83/430) with confidence interval (CI) 95%=[0.15-0.20] were identified with DS. Their age ranged from one day to 12 years. The mean age of the diagnosis of DS was seven days and 18 months for the discovery of associated anomalies. The male sex was prevalent with a sex ratio of 1.07. The anomalies associated with DS were present in 74.7% (IC 95%=[0.66-0.84]) of the patients. The most common anomaly was congenital heart defect (CHD), in 40.3% of associated anomalies in which the ventricular septal defect, atrio-ventricular septal defect and atrial septal defect were the prevalent lesions. In addition, the affected children were mainly exposed to acute bronchopneumopathy followed by brain and digestive infections.
Conclusion: The Down syndrome accounts for a significant portion of congenital malformations diagnosed in UH of Brazzaville with a high prevalence of associated CHD and an increased susceptibility to respiratory tract infections.