Congenital malformations

Question 1

What are the main etiologies of congenital malformations?

Answer 1

Genetic causes, such as chromosomal anomalies or single gene mutations.
Environmental conditions/exposures. (Rare cause).
Unknown cause.

Question 2

What is the most common type of major birth defect?

Answer 2

Congenital heart defects.

Question 3

True or false: Heart murmurs are the hallmarks for congenital heart defects, and are always present in instances of congenital heart defects.

Answer 3

False. Heart murmurs are the hallmark of congenital heart defect, but are not always present.

Question 4

True or false: Most infants with congenital heart defects are asymptomatic at birth.

Answer 4

True. Most are asymptomatic at birth, but those in need of treatment will develop symptoms.

Question 5

When during fetal life is it the artia and ventricles undergo partitioning?

Answer 5

In the fifth gestational week.

Question 6

Congenital heart defects can disrupt the normal blood flow through the heart. In what ways?

Answer 6

The flow can be slowed down.
The flow can be blocked completely.
The flow can go in the wrong direction or to the wrong place.

Question 7

What is the most common risk factor for congenital heart defects?

Answer 7

Chromosomal anomalies, e.g. Down’s syndrome.

However, most cases of congenital heart defects are of unknown cause.

Question 8

What is the tetralogy of Fallot?

Answer 8

1. Overriding aorta.
2. Pulmonary stenosis.
3. Right ventricle hypertrophy.
4. Ventricular septal defect.

Question 9

What are examples of congenital heart defects that reduce systemic blood flow?

Answer 9

Critical aorta stenosis.

Hypoplastic left heart syndrome (HLHS). (Severe underdevelopment of the left side of the heart.)

Question 10

What is hypoplastic left heart syndrome (HLHS)?

Answer 10

1. Hypoplastic descending aorta.
2. Hypoplastic left ventricle.
3. Large persisting ductus arteriosus.
4. Atrial septal defect.

Question 11

What are the most common types of congenital heart defects in terms of severity?

Answer 11

Mild (asymptomatic), e.g small ventricular septal defects. (35 % of cases.)
Surgical repair, e.g. biventricular functional heart. (35 % of cases.)

Question 12

What is the most common congenital heart defect?

Answer 12

Ventricular septal defect.

Question 13

How are congenital heart defects screened for?

Answer 13

Ultrasound.
Pulse-oxymetry.
Clinical examination - auscultation, etc.

Question 14

True or false: Most cases of cleft lip and/or palate are associated with syndromes.

Answer 14

False. 55-70% of cases are non-syndromic.

Question 15

What is omphalocele?

Answer 15

A rare abdominal wall defect in which the intestines, liver and occasionally other organs remain outside of the abdomen in a sac because of failure of the normal return of intestines and other contents back to the abdominal cavity during around the ninth week of intrauterine development.

Question 16

What is gastroschisis?

Answer 16

Similar to omphalocele, but the protruding organs are not covered by a protective membrane.

Question 17

What is meconium?

Answer 17

The earliest stool of an infant. Black, viscous/sticky like tar, and has no odor (”barnebek”).

Question 18

What is the most common congenital condition detected by prenatal ultrasound?

Answer 18

Hydronephrosis.

Question 19

What may be causes of renal pelvis dilatation during fetal life?

Answer 19

It could be a normal/transient condition.
Stenosis in pyeloureteric junction.
Stenosis in vesicoureteric junction.
Vesicoureteric reflux.

Question 20

What is Potter’s syndrome?

Answer 20

Potter’s syndrome describes the typical physical appearance caused by pressure in utero due to oligohydramnios, classically due to bilateral renal agenesis but it can occur with other conditions, including infantile polycystic kidney disease, renal hypoplasia and obstructive uropathy.

Question 21

Why is Potter’s syndrome usually fatal?

Answer 21

Hypoplastic lungs are the usual cause of fatality.

Question 22

What are common congenital CNS malformations?

Answer 22

Spina bifida/myelomeningocele.
Hydrocephalus.
Disorders of migration.

Question 23

What is spina bifida and how is it classified?

Answer 23

A birth defect in which there is incomplete closing of the spine and membranes around the spinal cord during early development in pregnancy.

Spina bifida occulta: Gap in the spine’s bones, but the spinal cord and its covering do not push through it.
Meningocele: Sac of fluid present at the gap in the spine.
Myelomeningocele: Cord tissue extends into the meningocele.

Question 24

What are consequences of myelomeningocele?

Answer 24

Variable sensory and motor impairment. “Always” problems with bladder and bowel control.
Orthopedic problems (alike scoliosis and hip dysplasia).

Question 25

What is the germinal matrix?

Answer 25

A highly cellular and vascularized region in the brain from which cells migrate out during brain development.
It is the source of both neurons and glial cells, and is most active between 8-28 weeks gestation.