Abordaje diagnóstico del síndrome de down mediante la identificación de los signos ecográficos en el control del embarazo

Abstract

Introduction: Worldwide chromosomal abnormalities occur between 0.5 to 2%, and especially trisomy 21 cases, prenatal screening is important to detect these cases, which are common in pregnant women aged 35 or older years; Ultrasound is used to assess structural abnormalities in the fetus during pregnancy. Objective: To expose the different ultrasound signs in the control of pregnancy for an effective presumptive diagnosis of fetuses with Down syndrome. Development: In the first trimester ultrasound an increase in the thickness of the nuchal translucency is observed, absence of the nasal bone in 60-70%, short maxilla in 25% and in the Doppler ultrasound malformations of the ductus venosus in 80%. In the second trimester, between 60% and 91% of trisomy 21 cases are discovered, the findings are Nuchal fold thickness ≥ 6 mm, Short length of the femur, Hyperechoic intracardiac foci. Gray-scale Doppler ultrasound increases sensitivity for the detection of cardiac malformations. Conclusion: Markers of suspicion in the first trimester are a hypoplastic or absent nasal bone in 69% of fetuses with Down syndrome. In the second trimester, they are echogenic intracardiac foci, short length of the femur, ventriculomegaly; an increase in the cutaneous fold of the neck is the most sensitive (38.7%) and specific (95.9%) ultrasound marker of the second trimester. Sensitivity increases when ultrasound is combined with serum screening, integrated, and sequential screening.