- Low birth weight
- Congenital heart defects occur in around 80% and include:
- Holoprosencephaly - the brain fails to divide into two halves, resulting in the patient presenting with midline facial defects including:
- Other abnormalities of brain and CNS including:
- Additional craniofacial abnormalities include:
- Gastrointestinal abnormalities:
- Urogenital malformations:
- Hand and Feet abnormalities:
- Trisomy 18 (Edwards syndrome) has similar features and can be difficult to differentiate. Cytogenic studies and chromosomal analysis will confirm the diagnosis.
- Life expectancy is greatly reduced with a median survival of 2.5 days.
- 1 in 20 survive for longer than 6 months.
- Rarely, survival into the teens has been reported.
- Common causes of death include cardiac arrest, congenital heart disease and pneumonia.
- Profound mental retardation and developmental delay is seen in those who survive. Seizures and feeding difficulties are common.