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Handbook of Genetic Counseling/Fetal Alcohol Syndrome

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Fetal Alcohol Syndrome

Contracting

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  • Establish rapport with small talk-acknowledge prior contact (Jane)
  • Assess the understanding for the referral to genetics
  • Assess the concerns of the family and what they hope to learn today
  • Ascertain the level of understanding of FAS for those members present
  • Discuss topics to be covered during the appointment- review medical/family history, physical exam

Elicit Medical History

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It is important to establish a thorough, detailed medical history as certain medications (such as warfarin or valproic acid) may be teratogenic to the fetus or embryo if taken during pregnancy, and this may result in an exacerbation of congenital abnormalities.

Elicit Family History and Pedigree

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  • Confirm family history taken by Jane- any updates?
  • Often FAS-affected children are taken away from their biological parents and put into a foster or adoptive home, and a complete and thorough history is therefore important.
  • For the maternal history, the genetic counsellor should note such things as: documented high blood-alcohol concentration
          history of alcohol or other substance abuse 
          history of living with an alcohol abuser
          low socioeconomic class
          previous children with FAS
          low self esteem
          unemployment or social transience
          loss of a child to a foster home (Welch-Carre, 2005). 
  • The genetic counsellor should ask what kind of alcohol was consumed, the amount of consumption, and the frequency (Welch-Carre, 2005).
  • The genetic counsellor needs to record the child’s history, such as milestones, growth deficits, or CNS abnormalities (Welch-Carre, 2005).

Psychosocial Assessment

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  • Often FAS-affected children are taken away from their biological parents and put into a foster or adoptive home, and a complete and thorough history is therefore important.
  • For the maternal history, the genetic counsellor should note such things as: documented high blood-alcohol concentration
          history of alcohol or other substance abuse 
          history of living with an alcohol abuser
          low socioeconomic class
          previous children with FAS
          low self esteem
          unemployment or social transience
          loss of a child to a foster home (Welch-Carre, 2005). 
  • The genetic counsellor should ask what kind of alcohol was consumed, the amount of consumption, and the frequency (Welch-Carre, 2005).
  • The genetic counsellor needs to record the child’s history, such as milestones, growth deficits, or CNS abnormalities (Welch-Carre, 2005).

Definition

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  • Fetal alcohol syndrome is a disorder characterized by abnormalities in physical and mental development as a result of prenatal alcohol exposure.

Etiology

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  • Fetal alcohol syndrome (FAS) is caused by ethanol and/or its by-products
    • Ethanol is a teratogen that can cross the placenta and interrupt development during any stage of pregnancy.
    • Currently, it is not known whether alcohol is a mutagen affecting the ova or sperm prior to conception
  • Alcohol is now recognized as the most common major teratogen to which a fetus is liable to be exposed
  • 2 alcoholic drinks consumed per day by pregnant women have been shown to result in smaller birth size, while 4-6 drinks consumed per day show additional clinical features; both of the above can result in fetal alcohol effect (FAE)
  • FAE is a condition characterized by some, but not all, of the birth defects associated with FAS.
  • Most of the children believed to have FAS have been born to alcoholic women whose intake of alcohol was 8-10 or more drinks per day (Smith's pg. 555).
    • Although FAS is usually associated with exposure to large amounts of alcohol, this is not always the case.
    • The U.S. Surgeon General's conclusion that zero exposure to alcohol equals zero risk remains the only defensible true statement.

Incidence

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  • An accurate incidence rate of FAS has not been established
  • One study suggests approximately 1-3:1,000 live births (Management Of Genetic Syndromes pg.151).

Timing

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  • Alcohol exposure during the first trimester is associated with facial dysmorphology
  • Exposure during the second half of pregnancy is associated with growth deficiency
  • The brain appears to be uniquely vulnerable to alcohol
    • Variations in abnormalities are due to dose, frequency, timing of exposure and genetic factors of the mother and fetus.
    • The brain appears to be most vulnerable during the first trimester but can be affected throughout gestation.

Clinical Features

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  • Pre- and postnatal onset growth deficiency
  • Craniofacial anomalies
    • Mild to moderate microcephaly
    • Short palpebral fissures, ptosis, epicanthal folds
    • Maxillary hypoplasia
    • Short nose
    • Smooth philtrum with thin and smooth upper lip
    • Malformations of the inner ear
  • Skeletal anomalies
    • Joint anomalies, abnormal position and/or function
    • Scoliosis
    • Altered palmer crease patterns
    • Small distal phalanges
    • Small fifth fingernails
    • Clinodactyly of the 4th and 5th fingers
  • Cardiac Anomalies
    • Heart murmur (usually disappears by age 1)
    • VSD- most common heart defect in children with FAS
  • Genitourinary
    • Renal anomalies are reported to occur at an increased frequency
    • Renal hypoplasia or hydronephrosis
  • Occasional abnormalities
    • Cleft lip with or without cleft palate
    • Micrognathia
    • Short or webbed neck
    • 10-20% have cervical vertebral malformations
    • Tetralogy of Fallot
    • Hydrocephalus
    • Strawberry hemangiomata
  • Brain Dysfunction
    • Ethanol exposure leads to structural alterations of the brain resulting in cognitive and behavioral dysfunction
    • Most serious consequence of heavy prenatal alcohol exposure
    • Diminished brain cell number and intelligence
    • Heterotopias (faulty migration) of neurons
    • Measures of brain dysfunction:
      • MR (not present in many)
      • Microcephaly
      • Epilepsy or other hard neurological signs
      • Subtle problems such as clumsiness and difficulties with visual-motor integration
      • Sleep regulation difficulty
      • Clinical features of ADHD
      • Poor inter-social relationships
  • Intelligence
    • The average IQ for patients with FAS is 63, which is considered mild mental retardation. Some patients with FAS have higher intelligence; patients can have a wide range of IQ's, including normal.
    • Developmental delay
    • Fine motor dysfunction
    • Irritability in infancy
    • Irregular patterns of academic achievement:
      • Hyperactivity (ADHD)
      • Poor communication skills
      • Difficulty remembering instructions
      • Irritability
      • Disorganization

Diagnostic Criteria

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  • Cardinal features for FAS were established in the late 1970's
  • The condition can be characterized by:
    • A specific facial appearance
    • Evidence of organic brain damage
    • Growth deficiency
    • Alcohol exposure during gestation
  • A problem with the above criteria is the precision of measurement of each component (How many facial characteristics need to be present? How small must the child be?)
    • Overcome this problem with the 4-digit diagnostic code
    • 4 key diagnostic features (see above) are evaluated on a 4 point scale
    • A score of 1 reflects complete absence of the FAS feature and 4 reflecting a strong classic presence of the FAS feature
    • A score of 4444 denotes the most severe form of FAS while 1111 denotes a complete absence of FAS.
    • Scores between 1111 and 4444 represent the broad spectrum of outcome and exposure combinations

Risk Assessment

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  • Risk of recurrence varies and is dependent upon the woman's drinking status during future pregnancies.
  • Women who do not drink during pregnancy have a 0% risk of recurrence
  • Women who are chronic alcoholics are at an increased risk of having a child with FAS.
  • Children with FAS have an increased risk of being alcoholics in adulthood.

Differential Diagnosis

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  • Glue and solvent sniffing (toluene exposure) throughout pregnancy can produce infants who look strikingly like children with FAS
  • Seizure medications such as phenobarbital, valproic acid, and hydantoin can result in facial anomalies and organic brain damage

Management and Treatment

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  • Carefully monitor growth by plotting on a growth curve
    • Children with FAS can be born as a SGA infant
    • Or birth size can be normal and fall below the growth curve during the 1st 12-18 months of life
  • Psychological and psychiatric assessments including a developmental evaluation (medication can be prescribed as necessary)
  • Family therapy
  • Special education in a variety of categories
  • Routine ophthalmologic evaluations
  • Routine audiological evaluations
  • Cardiovascular clinical evaluation at time of diagnosis
  • Renal ultrasounds (if patient has had a UTI or enuresis after age 8)
  • Clinical evaluation for spinal curvature
  • Implementing coping strategies in the home/classroom
    • Maintain a structured environment
    • Establish routines
    • Give short and concise instructions
    • Respond consistently to the child's behavior
    • Acknowledge the child's successes EVERY DAY
    • Redirect unacceptable behavior
    • Be patient
    • REPEAT…REPEAT….REPEAT

Psychosocial Issues

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  • Biological mothers are often alcohol abusers and have a variety of health problems of their own.
  • One study shows that 50% of these mothers are missing or dead within 5 years of the birth.
  • 50% of children with FAS are in foster or adoptive care
  • Generally the reasons for final separation from the biological parent(s) were abuse and neglect.
  • This movement from home to home compounded by abuse and neglect usually has a profound effect on the child and his/her behavior.

Support Groups

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  • Fetal Alcohol Syndrome Family Support Group
C/O Cardinal Hill of Northern Kentucky
212 Levassor Avenue
Covington, Kentucky 41014
(859) 491-1171

References

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  • Jones KL (1997). Smith's Recognizable Patterns of Human Malformation. Philadelphia: W.B. Saunders Company.
  • Allanson JE, Cassidy SB (2001). Management of Genetic Syndromes. New York: Wiley-Liss, Inc.
  • Fetal Alcohol Syndrome: A Handbook for Parents and Caregivers. The University of New Mexico (1999)

Notes

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The information in this outline was last updated in 2002.