Snapshot A 40-year-old woman gave birth to a girl at 39 weeks gestation. She had been lost to follow-up after her first prenatal appointment, and reports that she felt well during the pregnancy. The neonate born has significant cleft lip and cleft palate and microcephaly. An ultrasound shows ventricular septal defect of the heart as well as cerebral malformations. The neonate passes away a few hours later. The pediatrician informs the family that this child likely had an autosomal trisomy disorder. Introduction Overview login to view 1 more bullet Epidemiology Incidence login to view 2 more bullets Risk factors login to view 1 more bullet ETIOLOGY Genetics login to view 2 more bullets Associated conditions login to view 2 more bullets Presentation Symptoms login to view 6 more bullets Physical exam login to view 8 more bullets Imaging Fetal ultrasound login to view 6 more bullets Studies Genetic testing login to view 3 more bullets Differential Viable Autosomal Trisomies Trisomy 13 Trisomy 18 Trisomy 21 Epidemiology Trisomy 13 is the least common viable trisomy It is also the most severe Trisomy 21 is the most common viable trisomy Trisomy 21 is the most common viable trisomy Prognosis Death by age 1 Death by age 1 Normal prognosis First trimester serum markers ↓ β-HCG ↓ PAPP-A ↓ β-HCG ↓ PAPP-A ↑ β-HCG ↓ PAPP-A Second trimester serum markers Normal ↓ Alpha fetoprotein ↓ β-HCG ↓ Estriol Normal/↓ inhibin A ↓ Alpha fetoprotein ↑ β-HCG ↓ Estriol ↑ Inhibin A Treatment Management approach login to view 2 more bullets Surgical login to view 3 more bullets Complications Death Infections Malignancy Prognosis Many instances of Patau syndrome result in fetal demise Patients die by age 1 with median survival of 3 days There are reports of children surviving into teenage years Most common cause of death is cardiopulmonary arrest