1. Hemolytic disease of newborn
Dr. Tariq M.Roshan
Dept. of Hematology
PPSP

2. Objectives Definition & characteristics
ABO vs Rh hemolytic disease of the newborn
Pathogenesis
Incidence
Blood types of mother and baby
Severity of disease
Laboratory data
Prevention
Rh immune globulin
Tests for feto-maternal hemorrhage
Exchange transfusion protocol

3. Hemolytic disease of newborn
Hemolytic disease of the new born and fetus (HDN) is a destruction of the red blood cells (RBCs) of the fetus and neonate by antibodies produced by the mother
It is a condition in which the life span of the fetal/neonatal red cells is shortened due to maternal allo-antibodies against red cell antigens acquired from the father

4. Antibodies Five classes of antibodies
IgM
IgG
IgA
IgD
IgE
Blood groups specific antibodies are
IgM and rarely

5. Biochemistry of antibodies
Made from four polypeptide chains
Two light (L) chains
Two identical heavy (H) chains
Each class has immunologically distinct heavy chain

6. Biochemistry of antibodies
IgG1
IgG2
IgG3
IgA
IgM
IgE
Compliment fixation ++ +
+++ -
Placental transfer
Lymphocyte / macrophage FcR binding

7. Blood group antibodies
Blood group antibodies can be classified as
Naturally occurring and immune antibodies
Depending on presensitization
Cold and warm antibodies
Thermal range of antibodies
Most natural Abs are cold & some e.g wide thermal range like Anti A and Anti B
Most immune Abs are warm and can destroy red cell in-vivo
Complete and incomplete antibodies
Depends on agglutination of saline suspended red cells
IgM is complete antibody; most naturally occurring antibodies are complete and of IgM class
IgG is incomplete antibody

8. Antibodies of ABO system
Anti- A
Naturally occurring
Immune
Anti- B
Anti- A1
Anti- H

9. Antibodies of Rh system
Naturally occurring
Anti- E
Occasionally anti-D and anti Cw
Immune antibodies
D antibodies are more immunogenic
Other are anti c, E, e, C.
Most common is anti- E
After anti- D, anti- c is the common cause of HDN
(The vast majority of Rh antibodies are IgG and do not fix complement)

10. Antibodies from other blood group systems
Anti- K
Kell blood group system
Usually is immune antibody
Warm Ab
Anti- Jka
Kidd blood group system

11. Complement
Complements are series of proteins, present in plasma as an inactive precursors
When activated and react sequentially with each other they mediate destruction of cells and bacteria
Complement activation involves two stages
Opsonization
Lytic stage

12. Complement
Antibodies can fix complement and cause rapid destruction of red cells
Destruction depends on the amount of antibody and complement
In ABO- incompatible transfusion no surviving A or B red cells can be seen after 1 hour of transfusion
Why?
Remember naturally occurring Abs. are IgM and fix complement mediating the hemolysis

13. Disease mechanism - HDN
There is destruction of the RBCs of the fetus by antibodies produced by mother
If the fetal red cells contains the corresponding antigen, then binding of antibody will occur to red cells
Coated RBCs are removed by mononuclear phagocytic system

14. Neonatal
liver is immature and
unable to handle
bilirubin
Unconjugated
bilirubin
Conjugated
bilirubin
Coated red blood cell
are hemolysed in
spleen

15. Pathogenesis; before
birth

16. Pathogenesis; after
delivery

17. Clinical features Less severe form Severe forms Intrauterine death
Mild anemia
Severe forms
Icterus gravis neonatorum (Kernicterus)
Intrauterine death
Hydrops fetalis
Oedematous, ascites, bulky swollen & friable placenta
Pathophysiology
Extravascular hemolysis with extramedullary erythropoiesis
Hepatic and cardiac failure

18. Hemolytic disease of newborn HDN
BOFORE BIRTH
Anemia (destruction of red cells)
Heart failure
Fetal death
AFTER BIRTH
Build up of bilirubin
Kernicterus
Severe growth retardation

20. P N
Blood film of a fetus affected by HDN showing polychromasia
and increased number of normaoblasts

21. Rh HEMOLYTIC DISEASE OF NEWBORN
Antibodies against
Anti-D and less commonly anti-c, anti-E
Mother is the case of anti-D is Rh -ve (negative)
Firstborn infant is usually unaffected
Sensitization of mother occurs
During gestation
At the time of birth
All subsequent offspring inheriting D-antigen will be affected in case of anti-D HDN

22. Fetomaternal Hemorrhage
Pathogenesis
Fetomaternal Hemorrhage
Maternal Antibodies formed against Paternally derived antigens
During subsequent pregnancy, placental passage of maternal IgG antibodies
Maternal antibody attaches to fetal red blood cells
Fetal red blood cell hemolysis

24. Factors affecting immunization and severity
Antigenic exposure
Host factors
Antibody specificity
Influence of ABO group
ABO-incompatible Rh- positive cells will be hemolysed before Rh antigen can be recognized by the mother’s immune system

25. Diagnosis and Management
Cooperation between
Pregnant patient
Obstetrician
Her spouse
Clinical laboratory

26. Recommended obstetric practice
History; including H/O previous pregnancies or and disease needing blood transfusion
ABO and Rh testing
Antibody detection;
To detect clinically significant IgG Ab which reacts at 370C
Repeat testing required at 24 or 28 weeks if first test negative
Antibody specificity
Parental phenotype
Amniocyte testing

27. Amniocentesis and cordocentesis
Antibody titres
Difference of 2 dilutions or score more than 10 is significant
Amniocentesis and cordocentesis
Concentration of bilirubin
Spectrophotometric scan
Indirect method
Increasing or un-change OD as pregnancy advance shows worsening of the fetal hemolytic disease
Fetal blood sample can be taken and tested for
Hb, HCT, blood type and DCT (Direct Coombs test)
Percutaneous
Umbilical blood
sampling

28. Liley graph

29. Diagnosis and Management contd.
Intrauterine transfusion
Zone II or III
Cordocentesis blood sample Hb less than 10g/dl
Ultrasound evidence of hydrops
Early delivery
Phototherapy
Newborn transfusion
Exchange transfusion
Effects of transfusion
Removal of bilirubin
Removal of sensitized RBCs, and antibodies
Suppression of incompatible erythropoiesis

30. Diagnosis and Management contd.
Selection of blood
Group O RBCs
Rh-negativve units for Rh-negative case
Whole blood group O
Blood less than 7 days old

31. Diagnosis and Management contd.

32. Prevention of Rh- HDN Prevention of active immunization
Administration of corresponding RBC antibody (e.g anti-D)
Use of high-titered Rh-Ig (Rhogam)
Calculation of the dose
Kleihauer test for fetal Hb

33. Mechanism of action
Administered antibodies will bind the fetal Rh- positive cells
Spleen captured these cells by Fc-receptors
Suppressor T cell response is stimulated
Spleen remove anti-D coated red cells prior to contact with antigen presenting cells “antigen deviation”

34. ABO HEMOLYTIC DISEASE OF NEW BORN
For practical purpose, only group O individuals make high titres IgG
Anti-A and anti-B are predominantly IgM
ABO antibodies are present in the sera of all individuals whose RBCs lack the corresponding antigens

35. ABO HDN contd. Signs and symptoms Laboratory findings Treatment
Two mechanism protects the fetus against anti-A and anti-B
Relative weak A and B antigens o fetal red cells
Widespread distribution of A & B antigen in fetal tissue diverting antibodies away from fetal RBCs
Anemia is most of the time mild
ABO- HDN may be seen in the first pregnancy
Laboratory findings
Differ from Rh- HDN; microspherocytes are characteristic of ABO- HDN
Bilirubin peak is later; 1- 3 days after birth
Collection of cord blood and testing eluates form red cells will reveal anti-A or anti-B
Treatment
Group O donor blood for exchange transfusion which is rarely required

36. HDN- due to other antibodies
Anti-c
Usually less severe than that cause by Anti-D
Anti-K
May cause severe fetal anemia
Blood transfusion for the treatment should lack the appropriate antigen

37. Summary.
Hemolytic disease of newborn occurs when IgG antibodies produced by the mother against the corresponding antigen which is absent in her, crosses the placenta and destroy the red blood cells of the fetus.
Proper early management of Rh- HDN saves lives of a child and future pregnancies
ABO- HDN is usually mild
Other blood group antigens can also cause HDN