Congenital abnormality and teratology

Question 1

Congenital anomaly

Answer 1

Abnormality of structure, function or disorder of metabolism that is present at birth and results in physical or mental disability

Question 2

Teratology

Answer 2

Study of causes and biological processes leading to abnormal development at fundamental and clinical level, and appropriate measures for prevention

Question 3

Most common, severe congenital anomalies

Answer 3

Heart defects

Neural tube defects

Down syndrome

Question 4

Risk factors of congenital anomalies

Answer 4

Genetic- inherited vs sporadic mutation

Infectious- rubella, syphillis, zika

Teratogens

Socio-economic/ demographics- nutritional, environment, age

Question 5

Prevention of congenital anomalies

Answer 5

Vaccination

Adequate intake of folic acid or iodine through fortification of staple foods or supplementation

Appropriate antenatal care

Question 6

Genetic/ chromosomal abnormalities

Answer 6

Consanguinity increases the prevalence of rare genetic congenital anomalies

Some ethnic communities have a comparatively high prevalence of rare genetic mutations such as cystic fibrosis and haemophilia C

Question 7

Screening for genetic disorders

Answer 7

In high risk patients e.g. those with previous recurrent pregnancy loss, or family history for a particular problem

In all patients through the UK AN screening program

Question 8

Malformation

Answer 8

Flawed development of a structure or organ

Question 9

Disruption

Answer 9

Alteration of an already formed organ

Question 10

Deformation

Answer 10

Alteration in structure caused by extrinsic pressures

Question 11

Dysplasia

Answer 11

Abnormal organisation of cells or tissues

Question 12

Syndrome

Answer 12

Multiple congenital abnormalities

Group of abnormalities due to a single aetiology

e.g. single chromosomal/ gene problem

Question 13

Sequence

Answer 13

Multiple congenital abnormalities but as a consequence of one abnormality

Question 14

Potters sequence

Answer 14

Renal agenesis leading to oligohydramnios leading to skeletal deformities

Question 15

Examples of chromosomal abnormalities

Answer 15

Down’s- trisomy 21

Edward’s- trisomy 18

Patau;s- trisomy 13

Turner’s- XO

Klinefelters- XXY

Question 16

Down’s syndrome

Answer 16

Facial features

• small nose and flat nasal bridge/ flat face
• large tongue that may stick out of mouth
• eyes that slant upwards and outwards
• a flat back of the head/ thickened skin

Other external features

• broad hands with short fingers
• single palmar crease
• below average weight and length at birth

Question 17

Edward’s syndrome T18

Answer 17

Facial abnormalities: small, abnormally shaped head, small jaw and mouth, low set ears, cleft lip/ palate

Skeletal abnormalities: long fingers that overlap, underdeveloped thumbs and clenched fists

Congenital heart defects: >90%

GI abnormalities: omphalocele, oesophageal atresia, tracheo-oesophageal fistula, umbilical or inguinal hernia, pyloric stenosis

Urogenital abnormalities: gonadal dysgenesis, horseshoe kidney, hydronephrosis, cystic kidneys, renal agenesis

Neurological problems: anencephaly, hydrocephaly, severe learning disability, seizures

Pulmonary hypoplasia

Question 18

Patau’s syndrome

Answer 18

Congenital heart defects: >80%

Facial abnormalities: cleft lip/ palate abnormally small eye or eyes or absence of 1 or both eyes, reduced distance between the eyes, microcephaly

GI abnormalities: omphalocele, exomphalos

CNS disorder: holoprosencephaly (single brain)

Abnormally small penis in boys, enlarged clitoris in girls

Skeletal: extra fingers or toes, rounded bottom feet

Question 19

Teratogens

Answer 19

An agent, such as a virus, a drug, or radiation, that causes malformation of an embryo or fetus

Question 20

Warfarin effects

Answer 20

Chondrodysplasia

Microcephaly

Question 21

Thalidomide effects

Answer 21

Limb defects/ heart defects

Question 22

Rubella effects

Answer 22

Rubella (deafness)

Question 23

Pesticides effects

Answer 23

Neural tube defects

Question 24

Hyperthermia effects

Answer 24

Fetal death

Neural tube defects

Question 25

Radiation effects

Answer 25

Microcephaly

Spina bifida

Question 26

Alcohol effects

Answer 26

FAS (maxillary hypopalsia, mental retardation)

Question 27

Androgen effects

Answer 27

Masculinisation of external genitalia

Question 28

Features of fetal alcohol syndrome

Answer 28

Epicanthal folds

Flat nasal bridge

Small palpebral fissures

Railroad track ears

Smooth philtrum

Thin upper lip

Question 29

Detecting congenital abnormalities

Answer 29

61% detected antenatally

8% at birth

6% at 2-4 weeks

18% after first month