Fetal alcohol syndrome

Fetal Alcohol Syndrome (FAS) is one of the leading preventable causes of intellectual disability in the United States. This syndrome occurs in newborns of mothers who consumed alcohol during pregnancy, resulting in a range of congenital abnormalities and developmental challenges.

Key Characteristics

Developmental and Physical Abnormalities

Babies born with FAS are at an increased risk of:

Developmental Retardation: Delays in both pre-and postnatal growth.
Microcephaly: Abnormally small head size due to impaired brain growth.
Facial Abnormalities:
- Smooth Philtrum: Absence of the normal groove between the nose and upper lip.
- Thin Vermillion Border: Thin upper lip.
- Small Palpebral Fissures: Shortened eye openings.
Limb Dislocations: Abnormalities in limb formation.
Heart Defects: Structural heart abnormalities.

Severe Complications

In the most severe cases, FAS may result in:

Heart-Lung Fistulas: Abnormal connections between the heart and lungs.
Holoprosencephaly: A failure in brain development, where the brain does not divide properly into two hemispheres.

Pathophysiology

One of the mechanisms of FAS is related to impaired migration of neuronal and glial cells, which are essential for brain development. Alcohol exposure disrupts the normal development and positioning of these cells, leading to structural and functional deficits in the brain.

Table of Key Features

Feature	Description
Intellectual Disability	Leading preventable cause in the U.S.
Growth Retardation	Both pre- and postnatal developmental delays
Microcephaly	Small head circumference due to reduced brain growth
Facial Dysmorphology	Smooth philtrum, thin vermillion border, small palpebral fissures
Skeletal Abnormalities	Limb dislocations
Cardiac Defects	Structural heart abnormalities; may include heart-lung fistulas
Neurological Defects	Holoprosencephaly in severe cases; impaired neuronal/glial migration

Points to Remember

Prevention: Avoiding alcohol during pregnancy is crucial to prevent FAS.
Irreversible Damage: FAS-related abnormalities are permanent and affect the child’s development throughout life.
Variable Severity: The extent of FAS varies depending on the timing, amount, and frequency of alcohol exposure during pregnancy.
Key Facial Features: Recognizing the characteristic facial features of FAS can aid in early diagnosis and intervention.

Bibliography

Centers for Disease Control and Prevention (CDC). “Fetal Alcohol Spectrum Disorders (FASDs).”
American Academy of Pediatrics. “Effects of Prenatal Alcohol Exposure on Child Development.”

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