Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Obstetrics and Gynaecology > Congenital abnormalities and their identification > Flashcards

Congenital abnormalities and their identification Flashcards

1
Q

What sort of abnormalities does congenital abnormalities encompass?

A

Structural deformities; chromosomal abnormalities; inherited diseases; intrauterine infections and drug exposure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a screening test?

A

Available for all women and gives a measure of the risk of the fetus being affected by a particular disorder. The ‘higher-risk’ patient can then be offered a diagnostic test.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a diagnostic test?

A

Performed on ‘high risk’ women to confirm or refute the possibility.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does a good screening test need to be?

A

Cheap, high sensitivity, high specificity, have an acceptable diagnostic test, condition should be serious,

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is sensitivity?

A

The proportion of subjects with the condition classified by the test as screen positive for the conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the negative predictive value?

A

The probability that a subject who is screen negative will not have the condition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is specificity?

A

The proportion of subjects without the condition who are classified as screen negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the screen positive rate?

A

The proportion of subjects who are classified as high risk by the test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the positive predictive value?

A

The probability that a subject who is screen positive will have the condition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the false positive rate?

A

The number classified as high risk who do not nevertheless have the condition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What methods can be used for prenatal testing of congenital abnormalities?

A

Maternal blood testing, ultrasound, fetal MRI, 3D ultrasound, amniocentesis, chorionic villus sampling, preimplantation genetic diagnosis (IVF)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What can maternal blood testing be used to prenatally test for?

A

Neural tube defects (Alpha fetoprotein raised), chromosomal abnormalities (beta-HCG, PAPPA, AFP, oestriol and inhibin A will be altered).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why is AFP raised in neural tube defects?

A

It is a product of the fetal liver, when the fetus has an open neural tube defect maternal levels are often raised

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Can US be used as a screening of diagnostic test?

A

Both. Screening for downs and cardiac (nuchal translucency). Diagnostic for structural abnormalities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

When is amniocentesis performed?

A

15 weeks gestation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the risk of miscarriage of amniocentesis?

A

1%, lower risk than CVS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

When is chorionic villous sampling performed?

A

11 weeks gestation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is CVS used to diagnose?

A

Chromosomal problems, autosomal dominant and recessive conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What (chromosomally) is downs syndrome?

A

Trisomy 21

20
Q

Why does trisomy 21 occur?

A

It is usually the result of random non-dysjunction at meiosis, although occasionally it arises as a result of a balanced chromosomal translocation in the parents

21
Q

At what age of mother is Downs syndrome more common?

A

In older mothers (over 35)

22
Q

What (chromosomally) is Edwards syndrome?

A

Trisomy 18

23
Q

What (chromosomally) is Patau’s syndrome?

A

Trisomy 13

24
Q

What are Edwards and Patau’s syndrome?

A

They are associated with major structural abnormalities and affected foetuses die in utero or shortly after birth

25
Q

What is Turner’s syndrome?

A

Single X chromosome (X0), affected individuals are female, infertile but with normal intellect

26
Q

What is Klinefelter’s syndrome?

A

47XXY. These males have normal intellect, small testes and are infertile

27
Q

What would a US show if the fetus had down syndrome?

A

Thickened nuchal translucency
Some structural abnormalities
Absent or short nasal bone
Tricuspid regurgitation

28
Q

What would maternal blood tests show if the fetus had down syndrome?

A 
Low PAPPA in 1st trimester
High beta-hCG (1st/2nd trimester)
Low AFP (1st/2nd trimester)
Low oestriol (2nd trimester)
High inhibin (2nd trimester)
29
Q

What prenatal tests are used to diagnose chromosomal abnormalities?

A

Amniocentesis and CVS

30
Q

What is the ‘combined test’ used to screen for down syndrome?

A

US and blood test (PAPPA and beta-hCG)

31
Q

What are some central nervous system structural abnormalities?

A

Neural tube defects, ventriculomegaly and akinesia

32
Q

What are neural tube defects?

A

The result of failure of closure of the neural tube, neural tissue is often exposed, allowing degeneration

33
Q

What is an example of a well-known neural tube defect?

A

Spina bifida

34
Q

What can the mother take to reduce the risk of neural tube defects?

A

0.4mg/day folic acid

35
Q

What is ventriculomegaly?

A

Enlargement of a ventricle(/s), particularly the lateral ventricle. Prognosis depends on the severity and cause

36
Q

What medical in utero therapies are available?

A

Steroids to mature lungs
Antiarrhythmic drugs
NSAIDs for polyhydramnios

37
Q

What examples of abdominal wall structural defects are there?

A

Exomphalos and gastroschisis

38
Q

What is exomphalos?

A

Abdominal contents protrude through the anterior abdominal wall but are covered in an amniotic sac.
50% are caused by a chromosomal problem. Good prognosis after postnatal surgery

39
Q

What is gastroschisis?

A

Congenital defect in the anterior abdominal wall just lateral to the umbilical cord
Rarely associated with other abnormalities.
>90% survive after postnatal surgery

40
Q

What is a diaphragmatic hernia?

A

The abdominal contents herniate into the chest, causing pulmonary hypoplasia.

41
Q

What is polyhydramnios?

A

Liquor volume increased. Normal volume varies with gestation, but deepest liquor pool >10cm generally considered abnormal

42
Q

What are the causes of polyhydramnios?

A 
Idiopathic
Fetal infection
Rhesus isoimmunisation
Maternal disorders (DM, renal failure)
Duodenal atresia
Twins
Fetal anomaly (Down, Edward)
Fetal cardiac failure
43
Q

What are the clinical features of polyhydramnios?

A

Maternal discomfort. Large for dates, taut uterus, fetal parts difficult to palpate

44
Q

What are the complications of polyhydramnios?

A

Preterm labour, maternal discomfort, abnormal lie and malpresentation

45
Q

How would you treat polyhydramnios?

A

NSAIDs to reduce fetal urine output

46
Q

List 5 complications of amniocentesis.

A
  1. Preterm labour and delivery
  2. Chorioamnionitis
  3. Fetal respiratory distress
  4. Fetal trauma
  5. Red cell alloimmunisation in rhesus negative pregnancies
  6. Risk of miscarriage
47
Q

List 5 causes of oligohydramnios.

A
  1. premature rupture of membranes
  2. fetal renal problems e.g. renal agenesis
  3. intrauterine growth restriction
  4. post-term gestation
  5. pre-eclampsia

Obstetrics and Gynaecology (27 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions