1M - Prenatal Diagnosis, Fetal Disorders and Fetal Therapy

Question 1

This is the science of identifying structural or functional abnormalities in developing fetus

Answer 1

Prenatal Diagnosis

Question 2

What are the three major categories of diagnostic evaluation in prenatal diagnosis?

Answer 2

Fetus at high risk of genetic or congenital disorder
Fetus at unknown risk from common congenital abnormalities
Fetus ultrasonographically discovered to have structural or developmental abnormalities

Question 3

Most common cause of congenital defect?

Answer 3

Aneuploidy

Question 4

Most common etiology of birth defect which happens during development? site an example

Malformation
Deformation
Disruption

Answer 4

Malformation

Ex: Spina Bifida

Question 5

Etiology of birth defect caused by mechanical forces which results in abnormal fetus development? Site example

Answer 5

Deformation

EX: Contractures caused by oligohydramnios

Question 6

Etiology of birth defect which happens when genetically normal tissue is modified as the result of specific insult? Site an example

Answer 6

Disruption

Ex: Damage from an amniotic band causing cephalocele or limb reduction abnormality

Question 7

Cluster of several abnormalities or defects? All abnormalities have the same cause. Site an example?

Answer 7

Syndrome

Trisomy 18

Question 8

All anomalies is caused by one specific insult? Site an example?

Answer 8

Sequence

Oligohydramnios leading to pulmonary hypoplasia, limb contractures and facial deformities

Question 9

Particular anomalies occur together frequently but do not seem to be linked etiologically? Site an example

Answer 9

Association

VATER - Vertebral defects, anal atresia, tracheoesophageal fistula with esophageal atresia and radial dysplasia

Question 10

Give two screenings for aneuploidy that every pregnant women should be offered?

Answer 10

Traditional or analyte based and Cell Free DNA testing

Question 11

what are two maternal serum used as analytes in aneuploidy testing?

Answer 11

HCG and PAPP-A

used together with sonographic measurement for nuchal translucency

Question 12

If tested positive for Down Syndrome during the first trimester, what will be the findings in HCG and PAPPA level?

Answer 12

HCG is higher and PAPPA is lower

Question 13

If tested positive for Trisomy 18 and Trisomy 13, what will be the finding in HCG and PAPPA level?

Answer 13

Levels of both analytes are lower

Question 14

What is the CRL length necessary before measuring nuchal translucency? And what measurement is associated with birth defects, increase or decrease?

Answer 14

38-45 and 84mm

an increase is associated with higher risk of birth defects. A measurement of 3 mm or more should receive counseling

Question 15

What are the serum markers for Fetal Down Syndrome during the second trimester?

Answer 15

Lower maternal serum AFP, Lower unconjugated estriol, Higher HCG, higher dimeric inhibin levels

Question 16

Second most common malformations?

Answer 16

Neural Tube defects

most common is cardiac defects

Question 17

What test are given for women at risk of neural tube defects?

Answer 17

AFP testing and targeted US

Amniocentesis and Karyotyping is performed for confirmatory test

Question 18

What is the most common risk factor for neural tube defects?

Answer 18

Family history

Question 19

Major serum protein in embryo-fetus analogous to

albumin which is produced first by the fetal yolk and later by the liver and GI tract?

Answer 19

AFP

Question 20

Describe the behavior of AFP in fetal serum and amniotic fluid vs maternal serum?

Answer 20

It steadily increases in fetal serum and amniotic fluid until 13 weeks, in which it decreases thereafter. It steadily increases in maternal serum after 12 weeks

Question 21

When is AFP screening offered according to ACOG?

Answer 21

at second trimester at 15-20 weeks

Question 22

Level of AFP in MoM to detect neural tube defect?

Answer 22

higher than 2.5 MoM

Question 23

Level of maternal serum estriol level to detect Smith Lemli Opitz syndrome and steroid sulfatase deficiency??

Answer 23

higher than 0.25 MoM

Question 24

This is characterized by facial malformations with mental and behavioral abnormalities associated with high estriol levels?

Answer 24

Smith Lemli Opitz Syndrome

Question 25

This is also known as C linked ichthyosis?

Answer 25

Steroid sulfatase deficiency

Question 26

This combines results of first and second trimester screening?

Answer 26

Integrated screening

Question 27

When are quadruple markers done?

Answer 27

15-21 weeks

Question 28

This screening strategy involves performing the first trimester screening and informing the patients of the results

Answer 28

Sequential screening If positive, a diagnostic test is done

Question 29

This screening strategy is made by identifying DNA fragments that are derived primarily from apoptotic trophoblasts, which are placental cells undergoing programmed cell death.

Answer 29

Cell free DNA screening

Question 30

When can cell free DNA screening be made?

Answer 30

After 9-10 weeks not gestational age dependent

Question 31

If cell-free DNA screening is performed as a secondary screen following a positive first- or second-trimester analyte-based test result, a normal result is not quite as reassuring. T or F?

Answer 31

True

Question 32

What measurement of nuchal skinfold is non assuring?

Answer 32

More than 6 mm tenfold risk for Down Syndrome

Question 33

Echogenic intracardiac focus is usually right sided or left sided?

Answer 33

Left

Question 34

Bilateral echogenic foci is associated with what genetic defect?

Answer 34

Trisomy 13 (Ptau Syndrome)

Question 35

What measurement of mild pelvis renal dilatation can approximately double the risk of down syndrome?

Answer 35

4 mm

Question 36

A bright echogenic fetal bowel increases the risk by 2 fold of what genetic defect?

Answer 36

Down syndrome

Question 37

Couples planning to have a pregnancy with third degree couples should be advised to screen for CF? T or F

Answer 37

False up to second degree relative and only those couples who are both caucasian

Question 38

What mutation causes cystic fibrosis?

Answer 38

Mutation of CFTR gene at the long arm of chromosome 7

Question 39

Classic cystic fibrosis presents as?

Answer 39

``` abnormal chloride levels in sweat chronic pulmonary disease pancreatic insufficiency liver disease obstructive asooospermia ```

Question 40

Most common cause of familial mental retardation?

Answer 40

Fragile X syndrome

Question 41

Fragile X syndrome is what kind of genetic defect?

Answer 41

X linked only boys can acquire it

Question 42

Autosomal recessive lysosomal-storage disease is characterized by absence of the hexosaminidase A enzyme

Answer 42

Tay Sachs disease

Question 43

Most common prenatal diagnostic procedure?

Answer 43

2nd trimester amniocentesis One at 14-20 weeks

Question 44

The first 1-2 ml of aspirate from amniocentesis is not used to amniocentesis but can be used for what test?

Answer 44

AFP testing Needle used in amniocentesis is 20-22 gauge

Question 45

Early amniocentesis is associated with procedure related pregnancy loss? true or false?

Answer 45

True

Question 46

When do we do chorionic villus sampling?

Answer 46

10-13 weeks

Question 47

This prenatal diagnostic procedure is used to assess for analysis of non immune hydrops?

Answer 47

Percutaneous umbilical cord blood sampling or fetal blood sampling or cordocentesis

Question 48

What diagnostic procedure is done to check for anemia?

Answer 48

Fetal cerebral artery velocimetry

Question 49

Arterial procedure is preferred in cordocentesis?

Answer 49

False because of risk of vasospasm and fetal bradycardia

Question 50

This procedure allows diagnosis of few hereditary and genetic disorders prior to implantation

Answer 50

Preimplantation genetic diagnosis blastomere biopsy through a hole made in zona pellucida

Question 51

What are the most common causes of fetal anemia?

Answer 51

Red cell alloimmunization - erythroblastosis fetalis or hemolytic disease of the newborn congenital infections - parvovirus b19 thalassemia fetomaternal hemorrhage

Question 52

What is the treatment for severe fetal anemia?

Answer 52

Antenatal fetal transfusion ○ Anti-D ○ Anti-Kell ○ Anti-c ○ Anti-E alloimmunization

Question 53

How is alloimmunization detected?

Answer 53

Indirect Coombs test

Question 54

What are the critical titer ranges for indirect coombs test?

Answer 54

1:8 to 1:32 ○ If the critical titer for anti-D antibodies is 1:16 - severe hemolytic disease ■ Except for Kell sensitization

Question 55

Most common alloimmunization?

Answer 55

Anti E alloimunization

Question 56

Which alloimmunization has a greater need for fetal or neonatal transfusion?

Answer 56

Anti-C alloimmunization

Question 57

When a d negative female is exposed to maternal d positive red cells and produces anti d antibodies that may affect the her fetus during pregnancy, what is this phenomenon called?

Answer 57

Grandmother effect

Question 58

Most frequent minor antigen?

Answer 58

Kell antigen

Question 59

Critical titer for kell sensitization?

Answer 59

1:8

Question 60

Most common cause of hemolytic disease in the newborn which causes hyperbilirubinemia?

Answer 60

ABO blood group incompatibility

Question 61

Treatment for ABO blood group incompatibilty?

Answer 61

Phototherapy and transfusion

Question 62

ABO incompatibility is more commonly seen in pregnancies after the first one? T or F

Answer 62

False it is more commonly seen during the first

Question 63

Pregnancy at risk of alloimmunization but below the titer value should be assessed every when during the pregnancy?

Answer 63

Every 4 weeks

Question 64

When being tested for fetal anemia, if the middle cerebral doppler velocity is more than 1.5 MoM the AOG is most probably?

Answer 64

Less than 34 - 35 weeks Fetal blood sampling should be considered

Question 65

What prenatal diagnostic procedure measures the amount of bilirubin concentration?

Answer 65

Amniotic fluid spectral analysis bilirubin is usually high during mid pregnancy middle cerebral velocimetry is more accurate

Question 66

What strongly influences the management of severe fetal anemia?

Answer 66

Gestational age

Question 67

Where should intravascular transfusion be made for fetal anemia?

Answer 67

Umbilical vein

Question 68

for severe, early-onset hemolytic disease in | the early 2nd trimester, where should transfusion be done?

Answer 68

fetal peritoneal cavity

Question 69

For those with fetal hydrops, where should transfusion take place?

Answer 69

fetal peritoneal cavity and umbilical vein

Question 70

What level of hematocrit is transfusion indicated?

Answer 70

30%

Question 71

What is the target hematocrit for non hydropic fetus?

Answer 71

40 - 50%

Question 72

How do we compute for the volume to be transfused?

Answer 72

estimated fetal weight in grams by 0.02 for each 10% rise needed for the hematocrit

Question 73

In severely anemic fetus at 18-24 weeks, how is does transfusion take place?

Answer 73

Less initially and then another one after 2 days and more every 2 to 4 weeks

Question 74

MCA peak systolic velocity threshold for severe | anemia following an initial transfusion is

Answer 74

1.70 MoM

Question 75

After transfusion, hematocrit drops by how many percent per day?

Answer 75

1% and more rapid if with hydrops

Question 76

To prevent anti d alloimmunization, what is the management?

Answer 76

Post partum administration of anti d immune globulin to at risk pregnancies within 72 hours of delivery Anti D Ig is given at the third trimester and after delivery for rh - unsensitized women

Question 77

Dose of anti d Ig given IM?

Answer 77

300 to 1500 IU

Question 78

Qualitative test for anti d antigen?

Answer 78

Rosette test

Question 79

If there is sufficient dose of anti d Ig given, what would be the result in indirect coombs test?

Answer 79

Positive

Question 80

molecular weak d phenotype of d variant is treated how?

Answer 80

managed as d positive no risk of alloimmunization and Ig is not needed

Question 81

Those with partial D antigens are treated how?

Answer 81

Treated with anti D Ig due to risk of D - alloimmunization

Question 82

What is the most commo presenting complaint in the presence of fetomaternal hemorrhage?

Answer 82

Decreased fetal movement

Question 83

This fetal heart pattern warrants immediate evaluation?

Answer 83

sinusoidal

Question 84

This is the most commonly used quantitative test for fetal red cells?

Answer 84

Kelihauer - Betke test or acid elution test limitations include those with B thalassemia and those near term who have started to produce Hgb A

Question 85

What is the fetoplacental blood volume at term?

Answer 85

125 ml/kg

Question 86

A more accurate method of quantitative testing for fetal red cells than KB test is?

Answer 86

Flow cytometry

Question 87

Most common cause of thrombocytopenia among newborns?

Answer 87

Alloimmune thrombocytopenia | HPA 1A - 80 - 90%

Question 88

What is the platelet count of a woman whose child has alloimmune thrombocytopenia?

Answer 88

normal

Question 89

What is the treatment for alloimmune thromobocytopenia?

Answer 89

IV Ig and prednisone

Question 90

An autoimmune disorder in which antiplatelet IgG antibodies attack platelet glycoproteins of the fetus?

Answer 90

Immune thrombocytopenia or Idiopathic thrombocytopenia

Question 91

This condition is caused by an excessive accumulation of serous fluid in the fetus?

Answer 91

Hydrops fetalis

Question 92

Diagnostic findings of hydrops fetalis sonogrpahically?

Answer 92

more than 2 effusions (pelural, cardiac or ascites) or 1 effusion plus anasarca or whole body edema Skin thickness of more than 5 mm placentomegaly - 4 cm in 2nd trimester and 6 cm in 3rd trimester hydramnios

Question 93

Immune hydrops is caused by?

Answer 93

Red cell alloimmunization Hgb values of less than 5g/dL

Question 94

What is more common, immune hydrops or non immune hydrops?

Answer 94

Non immune hydrops

Question 95

A form of aneuploidy which commonly cause non immune hydrops?

Answer 95

Turner Syndrome 45,XO

Question 96

If isolated ascites is found, what may be the most probable cause of hydrops?

Answer 96

Parvovirus B19 or meconium peritonitis

Question 97

If isolated edema is found in the upper torso or the dorsum of the hands and feet, what may be the most probable cause of hydrops?

Answer 97

Turner syndrome or Noonan syndrome or congenital lymphedema syndrome

Question 98

This is also called Triple Edema? The fetus, mother and placenta are all edematous

Answer 98

Mirror Syndrome associated with hydrops and severe preeclampsia indicated prompt delivery

Question 99

What is tachyarrhythmia foe the fetus?

Answer 99

more than 180 bpm

Question 100

What is bradyarrhythmia for the fetus?

Answer 100

Less than 110 bpm

Question 101

What do you call premature atrial contractions?

Answer 101

Ectopy

Question 102

Treatment for arryhtmias?

Answer 102

Antiarrhythmic agents

Question 103

Most common form of tachyarrhythmias?

Answer 103

SVT and atrial flutter

Question 104

ST is characterized by an abrupt increase in fetal heart rate to

Answer 104

180-300 bpm with a typical range of 200-240

Question 105

ST if untreated may further develop into?

Answer 105

reentrant tachycardia

Question 106

What is the most common etiology of fetal bradyarrhyhtmia?

Answer 106

Congenital heart block

Question 107

What treatment is given to fetus with sustained bradyarrhythmia?

Answer 107

maternal terbutaline

Question 108

What sound does premature atrial contractions form?

Answer 108

Dropped beats

Question 109

This is the most common fetal arrhythmia?

Answer 109

Premature atrial contractions

Question 110

Most common etiology of androgen excess in | females with 46, X disorders of sex development

Answer 110

Congenital adrenal hyperplasia

Question 111

What is the prenatal treatment for congenital adrenal hyerplasia?

Answer 111

Corticosteroid oral dexamethasone given to the mother at a dosage of 20 mg/kg/d up to 1.5mg per day, three divided doses

Question 112

What age of gestation is the critical period for genital development? and when should corticosteroid therapy start to prevent virilization?

Answer 112

7-12 weeks | 9 weeks

Question 113

Sonographically, this malformation is a well circumscribed lung mass that may appear solid and echogenic or may have one or multiple variably sized cysts

Answer 113

Congenital cystic adenomatoid malformation

Question 114

When can a Congenital cystic adenomatoid malformation lesion be considered as macrocystic?

Answer 114

More than 5 mm

Question 115

Treatment for congenital cystic adenomatoid malformation?

Answer 115

dexamethasone-6.25 mg every 12 hours for four doses, or betamethasone- 12.5 mg intramuscularly every 24 hours for two doses

Question 116

What is the preferred test for fetal thyroid diseases to help guide treatment?

Answer 116

Fetal blood sampling

Question 117

Thyroid disease if it manifests as a goiter and compresses the trachea and esophagus, can cause?

Answer 117

severe fetal hydramnios and neonatal airway compromise, also shoulder dystocia due to hyperextension of the neck

Question 118

A pregnant woman with maternal Grave's disease can cause what condition to the fetus?

Answer 118

Fetal thyrotoxicosis

Question 119

A pregnant woman in medication for Grave's disease can cause what condition to the fetus?

Answer 119

fetal hypothyroidisim

Question 120

Discontinuation of thyroid medications is recommended during pregnancy? True or false?

Answer 120

True

Question 121

When undergoing open fetal surgery, what procedure must the mother undergo to suppress both uterine contractions and fetal responses?

Answer 121

GETA

Question 122

Fetal surgery is thoracic masses are usually treated with corticosteroids and surgery is only reserved for fetus with hydrops during what age of gestation?

Answer 122

32 weeks

Question 123

Sonographically, it is a solid and/or cystic mass that arises from the anterior sacrum

Answer 123

Sacrococcygeal teratoma

Question 124

Fetoscopic surgery is done to monochorionic diamniotic twin with stage 2 to stage 4 twin twin transfusion syndrome. What weeks of gestation is it usually done?

Answer 124

16-26 weeks

Question 125

In congenital diaphragmatic hernia, what is the lung to head ration that confers no survival if present?

Answer 125

less than 0.6 Measurement of the right lung area, taken at the level of four-chamber view of the heart, divided by the head circumference