How Long Can Babies Live with Holoprosencephaly?

Symptoms of holoprosencephaly vary widely and may include: 

• Small head (microcephaly)
• Excessive fluid in the brain (hydrocephalus)
• Intellectual disability 
• Developmental delays
• Facial abnormalities
  • Closely spaced eyes
  • Depressed or narrow nasal bridge
  • Cleft lip and/or palate
• Tooth abnormalities (single central incisor)
• Epilepsy (seizures) 
• Endocrine abnormalities
• Defects in the pituitary gland that cause abnormally low blood sugar levels (hypoglycemia), low blood sodium levels, or genital abnormalities
• In severe and very rare cases, a single central eye (cyclopia)

Holoprosencephaly is a birth defect that occurs during the first few weeks of pregnancy. The exact cause is unknown in many cases. 

Risk factors for developing holoprosencephaly include: 

• Maternal diabetes in during pregnancy 
• Trisomy 13 and other chromosomal abnormalities
• Genetic changes in the genes SHH, SIX3, TGIF1, ZIC2, PTCH1, FOXH1, NODAL, CDON, FGF8, and GLI2
• Certain genetic syndromes in which there are other medical issues that affect organs in addition to the brain and face (e.g., Smith-Lemli-Opitz syndrome)

Imaging tests are often used to diagnose holoprosencephaly, which depend on the severity of the condition and whether it is suspected prenatally or in the neonatal period. 

Testing may include: 

• Prenatal ultrasound
  • May be able to detect facial abnormalities in severe HPE, especially the alobar subtype, within the first trimester
  • Milder forms of the condition may not be able to be detected
• Fetal magnetic resonance imaging (MRI) 
  • Can provide better imaging of subtle malformations identified on prenatal ultrasound during the third trimester of pregnancy 
• High-resolution MRI scans, which include thin-section image sequences in three orthogonal planes (axial, sagittal, and coronal) for infants suspected of HPE
• Computerized tomography (CT) scan

Children with mild holoprosencephaly may not be diagnosed until they are older. The average age at diagnosis is four years, with about 15% of patients diagnosed at 10 and 19 years of age.

Treatment for holoprosencephaly involves supportive care based on the specific medical issues each individual child has. Children may need to see a variety of different medical specialists. 

• Endocrinology evaluation to check for pituitary abnormalities
• Neurologist involvement to guide treatment for seizures, if present
• Plastic reconstructive surgery of cleft lip and palate or other facial features 
• A developmental pediatrician to help direct developmental therapies
• Clinical genetics evaluation and genetic counseling for patients and families once the diagnosis is made
  • Chromosome analysis and gene testing is often performed
  • Relatives of a child with holoprosencephaly may have an increased risk of having a child with holoprosencephaly
  • Some specific features suggest an increased risk for having another child with holoprosencephaly
• Other specialists involved with care may include: pediatricians, dentists, special education teachers, therapists, and psychologists