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Retrospective cohort of trisomy 18 (Edwards syndrome) in southern Brazil
Daniela Denardin1, Fabíola Elizabete Savaris1, André Campos da Cunha2
1Hospital Materno Infantil Presidente Vargas, Porto Alegre, Rio Grande do Sul, Brazil.
Context And Objective:
Trisomy 18 (T18), or Edwards syndrome, is a chromosomal disease characterized by a broad clinical picture and a poor prognosis. Our aim was to describe clinical, radiological and survival data of a cohort of patients prenatally diagnosed with T18.
Design And Setting:
Retrospective single cohort in the Fetal Medicine Service of Hospital Materno Infantil Presidente Vargas (HMIPV).
Methods:
All sequential patients with T18 registered at the Fetal Medicine Service of HMIPV between January 2005 and September 2013 were considered. We gathered their clinical, radiological and survival data and used the Kaplan-Meier test for survival analysis.
Results:
Ten patients were diagnosed with T18, of whom seven (70%) were female. The majority (90%) were referred due to malformations seen on ultrasound. The mean gestational age at the first evaluation was 25.5 weeks. At karyotyping, the defects were considered multiple in only four patients (40%). All the fetuses presented full trisomy of chromosome 18. The main abnormality observed was congenital heart disease (n = 7). Intrauterine death occurred in half of the patients (50%). All live patients (n = 5) were born through cesarean section presenting low weight and low Apgar scores. The median length of survival after birth was 18 days.
Conclusions:
T18 is associated with a high risk of fetal and neonatal death. The majority of the patients present major malformations identified through ultrasound, such as congenital heart defects, which could help in identifying such cases prenatally.
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