Congenital Development/Abnormalities

Question 1

Congenital abnormality/anomaly/birth defect

Answer 1

An abnormality in structure, function or metabolism present at birth causing physical or mental disability

Question 2

Common congenital abnormalities

Answer 2

Heart defects
Neural tube defects
Down’s Syndrome

Question 3

Causes of congenital abnormalities

Answer 3

Neonatal sepsis
Birth asphyxia and birth trauma
Preterm birth

Question 4

Risk factors for congenital abnormalities

Answer 4

Genetics (inherited or sporadic) e.g. consanguinity
SES/demographics e.g. nutrition (folate) or environment or age
Infections e.g. rubella, zika, syphilis
Teratogens
Ethnicity e.g. Ashkenazi Jews and Finns have an increased risk of CF and haemophilia C

Question 5

Classification of congenital abnormalities

Answer 5

Malformation
Deformation
Dysplasia
Disruption

Question 6

Malformation

Answer 6

Flawed development of structure or organ

Question 7

Deformation

Answer 7

Alteration of a structure due to extrinsic pressures

Question 8

Dysplasia

Answer 8

Abnormal organisation of cells or tissue

Question 9

Disruption

Answer 9

Alteration of an already formed organ

Question 10

Syndrome

Answer 10

A single chromosomal or gene problem resulting in multiple congenital abnormalities

Question 11

Sequence

Answer 11

Multiple congenital abnormalities developing as a consequence of one congenital abnormality e.g. renal agenesis leading to skeletal abnormalities

Question 12

Common syndromes

Answer 12

Down's (21)
Patau (13)
Edward's (18)
Kleinfelter (XXY)
Turner's (XO)

Question 13

Down’s syndrome features

Answer 13

Upwards and outwards slanted eyes
Flattened nasal bridge
Low-set folded ears
Flat back of the head
Below average weight and length at birth
Broad hands with short fingers
Mild to moderate learning difficulties
Cardiac defects
Duodenal atresia (narrowing or closure)

Question 14

Examples of teratogens

Answer 14

Warfarin - chondrodysplasia and microcephaly
Thalidomide - limb and heart defects
Rubella - deafness
Syphilis
Zika - microcephaly
Alcohol - FAS
Radiation - microcephaly and spina bifida
Androgens - masculinisation of external genitalia
Hyperthermia - foetal death and neural tube defects
Pesticides - neural tube defects

Question 15

Examples of teratogens

Answer 15

Warfarin - chondrodysplasia and microcephaly
Thalidomide - limb and heart defects
Rubella - deafness
Syphilis - congenital syphilis
Zika - microcephaly
Alcohol - FAS
Radiation - microcephaly and spina bifida
Androgens - masculinisation of external genitalia
Hyperthermia - foetal death and neural tube defects
Pesticides - neural tube defects

Question 16

When are teratogens likely to cause damage?

Answer 16

Between week 3-9 during organogenesis due to the peak sensitivity of different organs as they develop so this is period when most birth defects develop

Question 17

FAS signs

Answer 17

Upturned nose
Thin lip
Rail road track ears due to under development
Smooth philtrum (no cupid's bow)
Underperform in school

Question 18

Edwards syndrome features

Answer 18

Cleft lip/palate
Small head
Small jaw and mouth
Clenched fists with overlapping fingers
Congenital heart defects
Hernia
Horseshoe kidney/renal agenesis/cystic kidneys
Learning disabilities
Seizures
Flexed big toe
Usually die within first year of life

Question 19

Patau syndrome features

Answer 19

Congenital heart defect
Cleft lip/palate
Small or absent eye(s)
Microcephaly
Small penis or enlarged clitoris
Single-lobed brain
Usually die within days of birth

Question 20

Prevention of congenital abnormalities

Answer 20

Preimplantation genetic testing (IVF)
Antenatal screening - combined screening (week 10-14), 20-week anomaly scan
In-utero diagnostic tests e.g. amniocentesis or CVS

Question 21

Why should birth defects be detected?

Answer 21

Termination
Treat in-utero (e.g. cleft lip/palate, pulmonary shunts, transfusion), maternal, or post-delivery
Adapt time of delivery and birth plan
Prepare parents

Question 22

Female hermaphrodites

Answer 22

Congenital adrenal hyperplasia causes virilisation = male external genitalia

Question 23

Male hermaphrodites

Answer 23

Leydig cell hypoplasia (insensitive to LH)
Androgen insensitivity syndrome
Causes undervirilisation resulting in female external genitalia

Question 24

Swyer’s syndrome

Answer 24

Male hypogonadism/ XY gonadal dysgenesis

Due to alteration of SRY gene

Question 25

Hypospadias

Answer 25

Failure of urethral folds to fuse causing proximal

Surgical correction

Question 26

Cryptorchidism

Answer 26

Unilateral and bilateral undescended testes

A testis Cannot be manipulated into the bottom of the scrotum without undue tension of the spermatic cord

Question 27

Congenital kidney abnormalities

Answer 27

Duplex kidney
Unilateral or bilateral absent kidney
Mayer-Rokitansky syndrome
Polycystic kidneys
Vesicular urethral reflux (may correct after 5yrs)
Posterior urethral valves
Ureterocele
Hypospadias
Horseshoe kidney
Pelvic kidney
Megaureter
Zinner syndrome (ipsilateral agenesis and seminal vesicle cyst)
Buried penis (scrotal skin and penis merged)

Question 28

Partial or complete inguinal hernia in children

Answer 28

Due to insufficient closure or no closure of the Processus Vaginalis

Question 29

Hydrocoeles of the cord

Answer 29

The processus vaginalis does not close properly to form a second testis