The main signs of achalasia microcephaly syndrome involve the manifestation of each individual disease associated with the condition. Microcephaly can be primary, where the brain fails to develop properly during pregnancy, or secondary, where the brain is normal sized at birth but fails to grow as the child ages. Abnormalities will be observed progressively after birth whereby the child will display stunted growth and physical and cognitive development. The occipital-frontal circumference will be at or near the extreme lower end, the third percentile, indicating microcephaly. There are both genetic and behavioural causes of microcephaly.
