L9-11: Rh Isoimmunization, ABO Incompatability & Fetal Hydrops Flashcards

1
Q

def of Rh Isoimmunization

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

Synonyms of Rh Isoimmunization

A
  • Erythroblastosis fetalis
  • Hemolytic disease of newborn
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Rh Isoimmunization

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

Rh Genes

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

Most Important Rh gene

A

D gene β†’ Rh +ve.

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

Rh +ve person

A

homozygous (DD) or heterozygous (Dd).

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

Rh -ve person

A

only homozygous (dd).

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

Rh Antigens

A

5 Ags (C, D, E, c, e) on surface of RBCs (no lower d Ag).

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

Incidence of Rh Isoimmunization

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

Incidence of Rh Isoimmunization

  • Rh -ve persons
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Incidence of Rh Isoimmunization

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

Incidence of Rh Isoimmunization

  • the great difference () incidence of Rh -ve persons & incidence of Rh isoimmunization is explained by
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Etiology of Rh Isoimmunization

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

Etiology of Rh Isoimmunization

  • Any contact () Rh + ve fetal blood & maternal circulation
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Etiology of Rh Isoimmunization

  • Blood transfusion of Rh +ve blood to Rh -ve female at any age
A

…

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

pathogenesis of Rh Isoimmunization

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

pathogenesis of Rh Isoimmunization

  • Which Antigen?
A
  • 95% of cases of isoimmunization are caused by maternal sensitization against Rh Ag D however, other Rh Ags (C & E) may rarely initiate isoimmunization
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q
  • Once Rh isoimmunization has been initiated, the individual produces large amounts of Abs (2ry response) in response to small amounts of fetal blood.
A

…

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

pathogenesis of Rh Isoimmunization

  • Amount of Blood Needed
A

As little as 0.25 ml of fetal Rh +ve cells can lead to isoimmunization.

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

pathogenesis of Rh Isoimmunization

  • Type of Abs
A
  • Initially, anti-Rh IgM Abs are formed (it has large MW so, don’t cross placenta & don’t cause hemolysis of fetal RBCs).
  • This is followed by the formation of anti-Rh IgG Abs that cross placenta β†’ destruction of fetal RBCs.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

CP of Rh Isoimmunization

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

CP of Rh Isoimmunization

  • Degrees
A
  • Congenital hemolytic anemia: Mildest form
  • Icterus gravis neonatorum: Commonest form
  • Fetal hydrops: Rarest & most severe form
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

CP of Rh Isoimmunization

  • Congenital hemolytic anemia
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

CP of Rh Isoimmunization

  • Icterus gravis neonatorum
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

CP of Rh Isoimmunization

  • Fetal Hydrops
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Dx of Rh Isoimmunziation

A
  • Hx
  • Rh Typing
  • Indirect Coombs Test
  • US
  • X-Ray
  • Spectrophotometric analysis of AF
  • Fetal blood sampling
  • Neonatal blood sampling
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Dx of Rh Isoimmunziation

  • Hx
A

1) Past history: Previous blood transfusion.

2) Obstetric history: Previous affected baby or IUFD which may be recurrent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Dx of Rh Isoimmunziation

  • Rh Typing
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Dx of Rh Isoimmunziation

  • Indirect Coombs Test
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Indirect Coombs test in Rh Isoimmunziation

  • Aim
A

Detection of presence of anti-Rh Abs in maternal serum & determination of level of these Abs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Indirect Coombs test in Rh Isoimmunziation

  • Technique
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Dx of Rh Isoimmunziation

  • US
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Dx of Rh Isoimmunziation

  • X-Ray
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Dx of Rh Isoimmunziation

  • Spectrophotometric analysis of AF
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Spectrophotometric analysis of AF in Rh Isoimmunization

  • Aim
A
  • Determination of AF bilirubin level that reflects degree of fetal RBCs hemolysis.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Spectrophotometric analysis of AF in Rh Isoimmunization

  • Indications
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Spectrophotometric analysis of AF in Rh Isoimmunization

  • Procedure
A
  • Amniocentesis & sample of 5-10 ml of AF is taken.
  • Protect specimen from light as it decolorizes bilirubin.
  • Spectrophotometric analysis of AF
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Spectrophotometric analysis of AF in Rh Isoimmunization

  • Interpretation
A
38
Q

Spectrophotometric analysis of AF in Rh Isoimmunization

  • Liley Graph
A
39
Q

Fetal Blood Sampling in Rh Isoimmunization

A
40
Q

Fetal Blood Sampling in Rh Isoimmunization

  • Aim
A
41
Q

Fetal Blood Sampling in Rh Isoimmunization

  • Procedure
A

Through cordocentesis.

42
Q

Fetal Blood Sampling in Rh Isoimmunization

  • Indication
A
  • AF bilirubin level is in high zone 2 or zone 3 on Liley graph.
  • Instead of amniocentesis before 26 weeks (AF analysis isn’t reliable at this age).
43
Q

Fetal Blood Sampling in Rh Isoimmunization

  • Disadvantages
A

Complications of cordocentesis:

  1. More risky than serial amniocentesis.
  2. Feto-maternal Hge & consequently, massive ↑↑ in concentration of Abs.
  3. Thrombosis of umbilical vessels.
  4. Risk of fetal death (1.5%).
44
Q

Neonatal Blood Sampling in Rh Isoimmunization

A
45
Q

Neonatal Blood Sampling in Rh Isoimmunization

  • Aims
A
  • ABO grouping & Rh typing.
  • Hb level & Hct value.
  • Number of reticulocytes & nucleated RBCs.
  • Serum bilirubin level.
  • Direct Coombs test.
46
Q

Neonatal Blood Sampling in Rh Isoimmunization

  • Procedure
A

Taking 10 ml of cord blood immediately after birth

47
Q

DDx of Rh Isoimmunization

A
48
Q

Prevention of Rh Isoimmunization

A
  • Prevention of blood transfusion errors
  • Anti-D Ig administration
49
Q

Prevention of Rh Isoimmunization

  • Prevention of blood transfusion errors
A

Never to give Rh +ve blood to Rh -ve females.

50
Q

Prevention of Rh Isoimmunization

  • Anti-D Ig administration
A
51
Q

Anti-D Ig administration in Rh Isoimmunization

  • Value
A

Anti-D Ig will destroy Rh +ve RBCs in maternal Circulation before sensitization.

52
Q

Anti-D Ig administration in Rh Isoimmunization

  • indications
A
53
Q

Anti-D Ig administration in Rh Isoimmunization

  • time of adminstartion
A

Within 72 hours after sensitizing event.

54
Q

Anti-D Ig administration in Rh Isoimmunization

  • Calculation of Dose
A
55
Q

Principle of Kleihauer-Betke acid elusion test

A
56
Q

Plan managment in Rh Isoimmunization

  • Algorithm
A
57
Q

Managment of Rh Isoimmunization

  • If Rh -ve husband
A

No need for further testing

58
Q

Managment of Rh Isoimmunization

  • if Rh +ve husband
  • US Showing fetal hydrops
A
  • cordocentesis & IUT then delivery after lung maturity
59
Q

Managment of Rh Isoimmunization

  • Rh +ve Husband
  • -ve indirect Coomb’s test
A

Repeat at 20, 24 & 28 weeks β†’ if remain -ve:

  1. Antepartum anti-D Ig at 28 & 34
  2. Allow spontaneous delivery.
  3. Postpartum anti-D Ig if neonate is
60
Q

Managment of Rh Isoimmunization

  • Rh +ve Husband
  • +ve indirect coomb’s test below critical level
A
61
Q

Managment of Rh Isoimmunization

  • Rh +ve Husband
  • +ve indirect coomb’s test >= critical level
A
62
Q

Intrauterine transfusion (IUT) in Rh Isoimmunization

A
62
Q

Lines of Managment of Rh Isoimmunization

A
  1. Management during pregnancy:
    - IUT
    - Adjuvant methods to ↓↓ fetal hemolysis
  2. Management of delivery
  3. Neonatal Care
63
Q

Intrauterine transfusion (IUT) in Rh Isoimmunization

  • indications
A
  • Fetal hydrops
  • significant fetal anemia (Hb deficit > 2 gm/dl from mean for normal fetuses or Hct value < 30%).
64
Q

Intrauterine transfusion (IUT) in Rh Isoimmunization

  • Types
A
65
Q

Intrauterine transfusion (IUT) in Rh Isoimmunization

  • Type of Blood
A
  • O -ve blood compatible with maternal blood (the best for severely hydropic fetuses is packed RBCs).
66
Q

Intrauterine transfusion (IUT) in Rh Isoimmunization

  • Calculation of amount needed
A

1) ml/gm of fetal weight.
2) (GA in weeks - 20) x 10.

67
Q

Adjuvant methods to ↓↓ fetal hemolysis in Rh Isoimmunization

A

Have no value
a. Promethazine therapy.
b. Plasmapheresis.
c. Immunosuppressive agents.

68
Q

Management of delivery in Rh Isoimmunization

  • Time of Delivery
A

See plan of management.

69
Q

Management of delivery in Rh Isoimmunization

  • Method of Delivery
A

Either VD or CS depending on fetal condition.

70
Q

Management of delivery in Rh Isoimmunization

  • Precautions
A
71
Q

Neonatal Care in Rh Isoimmunization

A
72
Q

Neonatal Care in Rh Isoimmunization

  • Care of Preterm
A

….

73
Q

Neonatal Care in Rh Isoimmunization

  • exchange Transfusion
A
74
Q

Neonatal Care in Rh Isoimmunization

  • Indications of Exchange Transfusion
A
75
Q

Neonatal Care in Rh Isoimmunization

  • Type of Blood in Exchange Transfusion
A

Fresh Rh -ve blood of homologous ABO group.

76
Q

Neonatal Care in Rh Isoimmunization

  • Amount of Blood in exchange transfusion
A

80 cc / pound body weight.

77
Q

Neonatal Care in Rh Isoimmunization

  • Phototherapy
A

in mild cases to decolorize yellow color of skin in jaundiced babies.

78
Q

Neonatal Care in Rh Isoimmunization

  • Phenobarbitone
A

May be used to ↑↑ hepatic bilirubin conjugation.

79
Q

Pathophysiology of ABO Isoimmunization

A

Women with blood group O may have anti-A & anti-B Abs from early life which may be augmented by pregnancy.

80
Q

Incidenece of ABO Isoimmunization

A

20% of all infants have ABO maternal blood group incompatibility however, only 5% of them show overt signs of hemolytic disease.

81
Q

Prevention of ABO Isoimmunization

A

ABO isoimmunization isn’t preventable but it is always much milder than Rh isoimmunization.

82
Q

CP of ABO Isoimmunization

A
83
Q

Criteria to Dx ABO Isoimmunization

A
84
Q

Another Name of Fetal Hydrops

A

Hydrops Fetalis

85
Q

Def of Fetal Hydrops

A

Presence of excess fluid in β‰₯ 2 body areas (as thorax, abdomen & skin).

86
Q

Classification of Fetal Hydrops

A
87
Q

Def of Non-Immune Fetal Hydrops

A
88
Q

Incidence of Non-Immune Fetal Hydrops

A

1/1700 pregnancies

89
Q

Etiology of Non-Immune Fetal Hydrops

A
90
Q

Dx of Non-Immune Fetal Hydrops

A
91
Q

Done

A

…