Structural Birth Defects

Question 1

What is the most common congenital brain defect & what outcomes are seen in children

Answer 1

Agenesis of the corpus callousum, mild learning difficulties & normal intelligence to more severe such as cerebral palsy, intellectual disability, seizures, more severe learning disabilities

Question 2

What is a dandy walker malformation & what symptoms are seen in children

Answer 2

Brain malformation with cerebellum & fourth ventricle - underdevelopment of middle part of cerebellum & cystic enlargement of fourth ventricle & posterior fossa
Developmental delays, hypotonia, spasticity, ataxia, seizures, respiratory issues, microcephaly ( ID in about 50%)

Question 3

What causes a dandy walker malformation

Answer 3

Anueploidy, CNVs, single gene disorder, or unknown

Question 4

What is holoprosencephaly & what symptoms are seen in children

Answer 4

Failure of forebrain to develop & separate into two halves
ID, seizures, microcephaly, hydrocephalus, tooth abnormalities, clefts, endocrine abnormalities, most severe with cyclopia

Question 5

What can cause holoprosencephaly

Answer 5

Maternal diabetes, anueploidy most commonly t13, single gene disorders, unknown
1/3 with chromosome anomalies

Question 6

What symptoms are associated with microcephaly & what causes it

Answer 6

Delays or ID, failure to thrive, poor feeding, ataxia, abnormal muscle tone, speech delays, seizures, facial deformities, vision or hearing
Aneuploidy, CNVs, single gene disorders, infection , maternal PKU, trauma, unknown

Question 7

What is a neural tube defect & what symptoms are associated

Answer 7

Opening in spine due to failure to close in development

Loss of feeling, weakness or paralysis in legs, bladder or bowel control problems, hydrocephalus, learning difficulties

Question 8

What causes neural tube defects

Answer 8

Usually multi factorial, aneuploidy, CNVs, poor folic acid intake, diabetes or obesity, teratogens, maternal fever

Question 9

When does cleft lip occur in development

Answer 9

4-7 weeks gestational age

Question 10

What fetal sex is more likely to have isolated cleft palate

Answer 10

Females 2:1

Question 11

What causes cleft lip with or without cleft palate

Answer 11

Usually multi factorial, can be caused by aneuploidy & single gene disorders

Question 12

What type of cleft lip is associated with which aneuploidy

Answer 12

Median cleft lip is associated with trisomy 13

Question 13

What conditions are associated with cleft lip & palate

Answer 13

Stickler syndrome, trisomy 13 & 18, van Der woude syndrome, teacher collins, Pierre robin sequence, 22q

Question 14

What percentage of cardiac defects are picked up on general ultrasound

Answer 14

40%

Question 15

What percent of babies with t21, t18, t13 have birth defects

Answer 15

50%, 85-90%, 80%

Question 16

What is congenital pulmonary airway malformation

Answer 16

Rare abnormal bronchial proliferation that results in cysts or masses - micro cystic or macro cystic

Question 17

What is a congenital diaphragmatic hernia & what is it associated with

Answer 17

Hole in diaphragm allowing abdominal organs into chest
30% have other anomalies
Fryns syndrome, pallister killian syndrome, trisomies

Question 18

What is tracheoesophageal fistula associated with

Answer 18

VACTERL, CHARGE, pallister hall, 22q, trisomy 18/13/21

50% have another birth defect

Question 19

What is duodenal atresia & what is it associated with

Answer 19

Duodenum isn’t formed correctly, also called double bubble sign
20-30% associated with t21, also seen with other birth defects, polyhydramnios, low birth weight, premature birth

Question 20

What is meconium ileus & what is it associated with

Answer 20

Obstruction of bowel because meconium is thicker & sticker than normal & gets stuck in ileum
20% have cystic fibrosis

Question 21

When are abdominal wall defects usually diagnosed

Answer 21

10-14 weeks gestational age

Question 22

What are the differences between omphalocele & gastroschisis

Answer 22

Omohalocele -usually in center, membrane covered, 50% aneuploidy, 1/3 BWS
gastroschisis - usually to right, no membrane, rarely associated with other birth defects or conditions

Question 23

What are the differences between multi cystic & polycystic kidney disease

Answer 23

Multi- usually large cysts that do not connect, no renal pelvis present on exam, not usually inherited, kidneys do not work & often lethal if bilateral, can be associated with other anomalies
Poly- usually appears echogenic & enlarged on ultrasound, single cysts not identifiable, varying onset, can be PCKD, potter sequence, Mencken gruber

Question 24

What percent of renal agenesis has a genetic cause

Answer 24

1-2% chromosome anomaly, 10% genetic condition: Fraser, VACTERL, MURCS association

Question 25

What type of twins can have twin to twin transfusion syndrome & why

Answer 25

Monochorionic twins, because they share a placenta

Question 26

What symptoms do the receipt & donor twins have in TTTS

Answer 26

Recipient-polyhydramnios, cardiac enlargement or failure, hydrops, thickened blood, overall worse outcome
Donor - oligohydamnios, risk of organ failure, growth restriction